2004 lines
74 KiB
Java
2004 lines
74 KiB
Java
/*
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* Copyright (C) 2009 The Android Open Source Project
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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package android.widget;
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import static android.view.flags.Flags.viewVelocityApi;
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import android.annotation.ColorInt;
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import android.annotation.NonNull;
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import android.compat.annotation.UnsupportedAppUsage;
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import android.content.Context;
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import android.content.res.Configuration;
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import android.content.res.TypedArray;
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import android.graphics.Canvas;
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import android.graphics.Rect;
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import android.os.Build;
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import android.os.Bundle;
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import android.os.Parcel;
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import android.os.Parcelable;
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import android.util.AttributeSet;
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import android.util.Log;
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import android.view.FocusFinder;
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import android.view.InputDevice;
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import android.view.KeyEvent;
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import android.view.MotionEvent;
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import android.view.VelocityTracker;
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import android.view.View;
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import android.view.ViewConfiguration;
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import android.view.ViewDebug;
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import android.view.ViewGroup;
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import android.view.ViewHierarchyEncoder;
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import android.view.ViewParent;
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import android.view.accessibility.AccessibilityEvent;
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import android.view.accessibility.AccessibilityNodeInfo;
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import android.view.animation.AnimationUtils;
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import android.view.inspector.InspectableProperty;
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import com.android.internal.R;
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import com.android.internal.annotations.VisibleForTesting;
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import java.util.List;
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/**
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* Layout container for a view hierarchy that can be scrolled by the user,
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* allowing it to be larger than the physical display. A HorizontalScrollView
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* is a {@link FrameLayout}, meaning you should place one child in it
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* containing the entire contents to scroll; this child may itself be a layout
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* manager with a complex hierarchy of objects. A child that is often used
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* is a {@link LinearLayout} in a horizontal orientation, presenting a horizontal
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* array of top-level items that the user can scroll through.
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*
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* <p>The {@link TextView} class also
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* takes care of its own scrolling, so does not require a HorizontalScrollView, but
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* using the two together is possible to achieve the effect of a text view
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* within a larger container.
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*
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* <p>HorizontalScrollView only supports horizontal scrolling. For vertical scrolling,
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* use either {@link ScrollView} or {@link ListView}.
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*
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* @attr ref android.R.styleable#HorizontalScrollView_fillViewport
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*/
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public class HorizontalScrollView extends FrameLayout {
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private static final int ANIMATED_SCROLL_GAP = ScrollView.ANIMATED_SCROLL_GAP;
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private static final float MAX_SCROLL_FACTOR = ScrollView.MAX_SCROLL_FACTOR;
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private static final String TAG = "HorizontalScrollView";
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/**
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* When flinging the stretch towards scrolling content, it should destretch quicker than the
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* fling would normally do. The visual effect of flinging the stretch looks strange as little
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* appears to happen at first and then when the stretch disappears, the content starts
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* scrolling quickly.
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*/
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private static final float FLING_DESTRETCH_FACTOR = 4f;
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private long mLastScroll;
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private final Rect mTempRect = new Rect();
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@UnsupportedAppUsage
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private OverScroller mScroller;
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/**
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* Tracks the state of the left edge glow.
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*
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* Even though this field is practically final, we cannot make it final because there are apps
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* setting it via reflection and they need to keep working until they target Q.
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* @hide
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*/
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@NonNull
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@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 124053130)
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@VisibleForTesting
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public EdgeEffect mEdgeGlowLeft;
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/**
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* Tracks the state of the bottom edge glow.
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*
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* Even though this field is practically final, we cannot make it final because there are apps
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* setting it via reflection and they need to keep working until they target Q.
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* @hide
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*/
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@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.P, trackingBug = 124052619)
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@VisibleForTesting
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public EdgeEffect mEdgeGlowRight;
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/**
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* Position of the last motion event.
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*/
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@UnsupportedAppUsage
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private int mLastMotionX;
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/**
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* True when the layout has changed but the traversal has not come through yet.
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* Ideally the view hierarchy would keep track of this for us.
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*/
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private boolean mIsLayoutDirty = true;
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/**
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* The child to give focus to in the event that a child has requested focus while the
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* layout is dirty. This prevents the scroll from being wrong if the child has not been
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* laid out before requesting focus.
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*/
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@UnsupportedAppUsage
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private View mChildToScrollTo = null;
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/**
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* True if the user is currently dragging this ScrollView around. This is
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* not the same as 'is being flinged', which can be checked by
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* mScroller.isFinished() (flinging begins when the user lifts their finger).
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*/
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@UnsupportedAppUsage
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private boolean mIsBeingDragged = false;
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/**
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* Determines speed during touch scrolling
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*/
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@UnsupportedAppUsage
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private VelocityTracker mVelocityTracker;
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/**
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* When set to true, the scroll view measure its child to make it fill the currently
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* visible area.
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*/
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@ViewDebug.ExportedProperty(category = "layout")
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private boolean mFillViewport;
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/**
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* Whether arrow scrolling is animated.
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*/
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private boolean mSmoothScrollingEnabled = true;
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private int mTouchSlop;
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private int mMinimumVelocity;
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private int mMaximumVelocity;
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@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
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private int mOverscrollDistance;
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@UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
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private int mOverflingDistance;
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private float mHorizontalScrollFactor;
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/**
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* ID of the active pointer. This is used to retain consistency during
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* drags/flings if multiple pointers are used.
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*/
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private int mActivePointerId = INVALID_POINTER;
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/**
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* Sentinel value for no current active pointer.
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* Used by {@link #mActivePointerId}.
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*/
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private static final int INVALID_POINTER = -1;
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private SavedState mSavedState;
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public HorizontalScrollView(Context context) {
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this(context, null);
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}
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public HorizontalScrollView(Context context, AttributeSet attrs) {
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this(context, attrs, com.android.internal.R.attr.horizontalScrollViewStyle);
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}
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public HorizontalScrollView(Context context, AttributeSet attrs, int defStyleAttr) {
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this(context, attrs, defStyleAttr, 0);
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}
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public HorizontalScrollView(
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Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
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super(context, attrs, defStyleAttr, defStyleRes);
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mEdgeGlowLeft = new EdgeEffect(context, attrs);
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mEdgeGlowRight = new EdgeEffect(context, attrs);
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initScrollView();
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final TypedArray a = context.obtainStyledAttributes(
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attrs, android.R.styleable.HorizontalScrollView, defStyleAttr, defStyleRes);
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saveAttributeDataForStyleable(context, android.R.styleable.HorizontalScrollView,
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attrs, a, defStyleAttr, defStyleRes);
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setFillViewport(a.getBoolean(android.R.styleable.HorizontalScrollView_fillViewport, false));
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a.recycle();
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if (context.getResources().getConfiguration().uiMode == Configuration.UI_MODE_TYPE_WATCH) {
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setRevealOnFocusHint(false);
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}
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}
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@Override
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protected float getLeftFadingEdgeStrength() {
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if (getChildCount() == 0) {
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return 0.0f;
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}
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final int length = getHorizontalFadingEdgeLength();
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if (mScrollX < length) {
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return mScrollX / (float) length;
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}
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return 1.0f;
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}
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@Override
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protected float getRightFadingEdgeStrength() {
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if (getChildCount() == 0) {
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return 0.0f;
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}
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final int length = getHorizontalFadingEdgeLength();
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final int rightEdge = getWidth() - mPaddingRight;
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final int span = getChildAt(0).getRight() - mScrollX - rightEdge;
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if (span < length) {
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return span / (float) length;
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}
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return 1.0f;
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}
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/**
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* Sets the edge effect color for both left and right edge effects.
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*
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* @param color The color for the edge effects.
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* @see #setLeftEdgeEffectColor(int)
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* @see #setRightEdgeEffectColor(int)
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* @see #getLeftEdgeEffectColor()
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* @see #getRightEdgeEffectColor()
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*/
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public void setEdgeEffectColor(@ColorInt int color) {
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setLeftEdgeEffectColor(color);
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setRightEdgeEffectColor(color);
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}
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/**
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* Sets the right edge effect color.
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*
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* @param color The color for the right edge effect.
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* @see #setLeftEdgeEffectColor(int)
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* @see #setEdgeEffectColor(int)
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* @see #getLeftEdgeEffectColor()
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* @see #getRightEdgeEffectColor()
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*/
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public void setRightEdgeEffectColor(@ColorInt int color) {
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mEdgeGlowRight.setColor(color);
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}
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/**
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* Sets the left edge effect color.
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*
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* @param color The color for the left edge effect.
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* @see #setRightEdgeEffectColor(int)
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* @see #setEdgeEffectColor(int)
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* @see #getLeftEdgeEffectColor()
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* @see #getRightEdgeEffectColor()
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*/
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public void setLeftEdgeEffectColor(@ColorInt int color) {
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mEdgeGlowLeft.setColor(color);
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}
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/**
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* Returns the left edge effect color.
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*
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* @return The left edge effect color.
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* @see #setEdgeEffectColor(int)
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* @see #setLeftEdgeEffectColor(int)
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* @see #setRightEdgeEffectColor(int)
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* @see #getRightEdgeEffectColor()
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*/
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@ColorInt
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public int getLeftEdgeEffectColor() {
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return mEdgeGlowLeft.getColor();
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}
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/**
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* Returns the right edge effect color.
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*
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* @return The right edge effect color.
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* @see #setEdgeEffectColor(int)
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* @see #setLeftEdgeEffectColor(int)
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* @see #setRightEdgeEffectColor(int)
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* @see #getLeftEdgeEffectColor()
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*/
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@ColorInt
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public int getRightEdgeEffectColor() {
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return mEdgeGlowRight.getColor();
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}
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/**
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* @return The maximum amount this scroll view will scroll in response to
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* an arrow event.
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*/
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public int getMaxScrollAmount() {
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return (int) (MAX_SCROLL_FACTOR * (mRight - mLeft));
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}
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private void initScrollView() {
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mScroller = new OverScroller(getContext());
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setFocusable(true);
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setDescendantFocusability(FOCUS_AFTER_DESCENDANTS);
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setWillNotDraw(false);
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final ViewConfiguration configuration = ViewConfiguration.get(mContext);
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mTouchSlop = configuration.getScaledTouchSlop();
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mMinimumVelocity = configuration.getScaledMinimumFlingVelocity();
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mMaximumVelocity = configuration.getScaledMaximumFlingVelocity();
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mOverscrollDistance = configuration.getScaledOverscrollDistance();
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mOverflingDistance = configuration.getScaledOverflingDistance();
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mHorizontalScrollFactor = configuration.getScaledHorizontalScrollFactor();
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}
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@Override
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public void addView(View child) {
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if (getChildCount() > 0) {
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throw new IllegalStateException("HorizontalScrollView can host only one direct child");
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}
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super.addView(child);
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}
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@Override
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public void addView(View child, int index) {
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if (getChildCount() > 0) {
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throw new IllegalStateException("HorizontalScrollView can host only one direct child");
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}
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super.addView(child, index);
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}
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@Override
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public void addView(View child, ViewGroup.LayoutParams params) {
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if (getChildCount() > 0) {
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throw new IllegalStateException("HorizontalScrollView can host only one direct child");
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}
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super.addView(child, params);
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}
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@Override
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public void addView(View child, int index, ViewGroup.LayoutParams params) {
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if (getChildCount() > 0) {
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throw new IllegalStateException("HorizontalScrollView can host only one direct child");
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}
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super.addView(child, index, params);
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}
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/**
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* @return Returns true this HorizontalScrollView can be scrolled
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*/
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private boolean canScroll() {
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View child = getChildAt(0);
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if (child != null) {
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int childWidth = child.getWidth();
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return getWidth() < childWidth + mPaddingLeft + mPaddingRight ;
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}
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return false;
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}
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/**
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* Indicates whether this HorizontalScrollView's content is stretched to
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* fill the viewport.
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*
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* @return True if the content fills the viewport, false otherwise.
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*
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* @attr ref android.R.styleable#HorizontalScrollView_fillViewport
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*/
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@InspectableProperty
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public boolean isFillViewport() {
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return mFillViewport;
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}
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/**
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* Indicates this HorizontalScrollView whether it should stretch its content width
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* to fill the viewport or not.
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*
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* @param fillViewport True to stretch the content's width to the viewport's
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* boundaries, false otherwise.
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*
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* @attr ref android.R.styleable#HorizontalScrollView_fillViewport
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*/
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public void setFillViewport(boolean fillViewport) {
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if (fillViewport != mFillViewport) {
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mFillViewport = fillViewport;
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requestLayout();
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}
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}
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/**
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* @return Whether arrow scrolling will animate its transition.
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*/
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public boolean isSmoothScrollingEnabled() {
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return mSmoothScrollingEnabled;
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}
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/**
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* Set whether arrow scrolling will animate its transition.
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* @param smoothScrollingEnabled whether arrow scrolling will animate its transition
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*/
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public void setSmoothScrollingEnabled(boolean smoothScrollingEnabled) {
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mSmoothScrollingEnabled = smoothScrollingEnabled;
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}
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@Override
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protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
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super.onMeasure(widthMeasureSpec, heightMeasureSpec);
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if (!mFillViewport) {
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return;
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}
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final int widthMode = MeasureSpec.getMode(widthMeasureSpec);
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if (widthMode == MeasureSpec.UNSPECIFIED) {
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return;
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}
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if (getChildCount() > 0) {
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final View child = getChildAt(0);
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final int widthPadding;
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final int heightPadding;
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final FrameLayout.LayoutParams lp = (LayoutParams) child.getLayoutParams();
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final int targetSdkVersion = getContext().getApplicationInfo().targetSdkVersion;
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if (targetSdkVersion >= Build.VERSION_CODES.M) {
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widthPadding = mPaddingLeft + mPaddingRight + lp.leftMargin + lp.rightMargin;
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heightPadding = mPaddingTop + mPaddingBottom + lp.topMargin + lp.bottomMargin;
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} else {
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widthPadding = mPaddingLeft + mPaddingRight;
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heightPadding = mPaddingTop + mPaddingBottom;
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}
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int desiredWidth = getMeasuredWidth() - widthPadding;
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if (child.getMeasuredWidth() < desiredWidth) {
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final int childWidthMeasureSpec = MeasureSpec.makeMeasureSpec(
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desiredWidth, MeasureSpec.EXACTLY);
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final int childHeightMeasureSpec = getChildMeasureSpec(
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heightMeasureSpec, heightPadding, lp.height);
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child.measure(childWidthMeasureSpec, childHeightMeasureSpec);
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}
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}
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}
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@Override
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public boolean dispatchKeyEvent(KeyEvent event) {
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// Let the focused view and/or our descendants get the key first
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return super.dispatchKeyEvent(event) || executeKeyEvent(event);
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}
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/**
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* You can call this function yourself to have the scroll view perform
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* scrolling from a key event, just as if the event had been dispatched to
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* it by the view hierarchy.
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*
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* @param event The key event to execute.
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* @return Return true if the event was handled, else false.
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*/
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public boolean executeKeyEvent(KeyEvent event) {
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mTempRect.setEmpty();
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if (!canScroll()) {
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if (isFocused()) {
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View currentFocused = findFocus();
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if (currentFocused == this) currentFocused = null;
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View nextFocused = FocusFinder.getInstance().findNextFocus(this,
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currentFocused, View.FOCUS_RIGHT);
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return nextFocused != null && nextFocused != this &&
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nextFocused.requestFocus(View.FOCUS_RIGHT);
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}
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return false;
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}
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boolean handled = false;
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if (event.getAction() == KeyEvent.ACTION_DOWN) {
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switch (event.getKeyCode()) {
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case KeyEvent.KEYCODE_DPAD_LEFT:
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if (!event.isAltPressed()) {
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handled = arrowScroll(View.FOCUS_LEFT);
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} else {
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handled = fullScroll(View.FOCUS_LEFT);
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}
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break;
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case KeyEvent.KEYCODE_DPAD_RIGHT:
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if (!event.isAltPressed()) {
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handled = arrowScroll(View.FOCUS_RIGHT);
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} else {
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handled = fullScroll(View.FOCUS_RIGHT);
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}
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break;
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case KeyEvent.KEYCODE_SPACE:
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pageScroll(event.isShiftPressed() ? View.FOCUS_LEFT : View.FOCUS_RIGHT);
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break;
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}
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}
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return handled;
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}
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private boolean inChild(int x, int y) {
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if (getChildCount() > 0) {
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final int scrollX = mScrollX;
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final View child = getChildAt(0);
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return !(y < child.getTop()
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|| y >= child.getBottom()
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|| x < child.getLeft() - scrollX
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|| x >= child.getRight() - scrollX);
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}
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return false;
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}
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private void initOrResetVelocityTracker() {
|
|
if (mVelocityTracker == null) {
|
|
mVelocityTracker = VelocityTracker.obtain();
|
|
} else {
|
|
mVelocityTracker.clear();
|
|
}
|
|
}
|
|
|
|
private void initVelocityTrackerIfNotExists() {
|
|
if (mVelocityTracker == null) {
|
|
mVelocityTracker = VelocityTracker.obtain();
|
|
}
|
|
}
|
|
|
|
@UnsupportedAppUsage
|
|
private void recycleVelocityTracker() {
|
|
if (mVelocityTracker != null) {
|
|
mVelocityTracker.recycle();
|
|
mVelocityTracker = null;
|
|
}
|
|
}
|
|
|
|
@Override
|
|
public void requestDisallowInterceptTouchEvent(boolean disallowIntercept) {
|
|
if (disallowIntercept) {
|
|
recycleVelocityTracker();
|
|
}
|
|
super.requestDisallowInterceptTouchEvent(disallowIntercept);
|
|
}
|
|
|
|
@Override
|
|
public boolean onInterceptTouchEvent(MotionEvent ev) {
|
|
/*
|
|
* This method JUST determines whether we want to intercept the motion.
|
|
* If we return true, onMotionEvent will be called and we do the actual
|
|
* scrolling there.
|
|
*/
|
|
|
|
/*
|
|
* Shortcut the most recurring case: the user is in the dragging
|
|
* state and they are moving their finger. We want to intercept this
|
|
* motion.
|
|
*/
|
|
final int action = ev.getAction();
|
|
if ((action == MotionEvent.ACTION_MOVE) && (mIsBeingDragged)) {
|
|
return true;
|
|
}
|
|
|
|
if (super.onInterceptTouchEvent(ev)) {
|
|
return true;
|
|
}
|
|
|
|
switch (action & MotionEvent.ACTION_MASK) {
|
|
case MotionEvent.ACTION_MOVE: {
|
|
/*
|
|
* mIsBeingDragged == false, otherwise the shortcut would have caught it. Check
|
|
* whether the user has moved far enough from their original down touch.
|
|
*/
|
|
|
|
/*
|
|
* Locally do absolute value. mLastMotionX is set to the x value
|
|
* of the down event.
|
|
*/
|
|
final int activePointerId = mActivePointerId;
|
|
if (activePointerId == INVALID_POINTER) {
|
|
// If we don't have a valid id, the touch down wasn't on content.
|
|
break;
|
|
}
|
|
|
|
final int pointerIndex = ev.findPointerIndex(activePointerId);
|
|
if (pointerIndex == -1) {
|
|
Log.e(TAG, "Invalid pointerId=" + activePointerId
|
|
+ " in onInterceptTouchEvent");
|
|
break;
|
|
}
|
|
|
|
final int x = (int) ev.getX(pointerIndex);
|
|
final int xDiff = (int) Math.abs(x - mLastMotionX);
|
|
if (xDiff > mTouchSlop) {
|
|
mIsBeingDragged = true;
|
|
mLastMotionX = x;
|
|
initVelocityTrackerIfNotExists();
|
|
mVelocityTracker.addMovement(ev);
|
|
if (mParent != null) mParent.requestDisallowInterceptTouchEvent(true);
|
|
}
|
|
break;
|
|
}
|
|
|
|
case MotionEvent.ACTION_DOWN: {
|
|
final int x = (int) ev.getX();
|
|
if (!inChild((int) x, (int) ev.getY())) {
|
|
mIsBeingDragged = false;
|
|
recycleVelocityTracker();
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Remember location of down touch.
|
|
* ACTION_DOWN always refers to pointer index 0.
|
|
*/
|
|
mLastMotionX = x;
|
|
mActivePointerId = ev.getPointerId(0);
|
|
|
|
initOrResetVelocityTracker();
|
|
mVelocityTracker.addMovement(ev);
|
|
|
|
/*
|
|
* If being flinged and user touches the screen, initiate drag;
|
|
* otherwise don't. mScroller.isFinished should be false when
|
|
* being flinged.
|
|
*/
|
|
mIsBeingDragged = !mScroller.isFinished() || !mEdgeGlowLeft.isFinished()
|
|
|| !mEdgeGlowRight.isFinished();
|
|
// Catch the edge effect if it is active.
|
|
if (!mEdgeGlowLeft.isFinished()) {
|
|
mEdgeGlowLeft.onPullDistance(0f, 1f - ev.getY() / getHeight());
|
|
}
|
|
if (!mEdgeGlowRight.isFinished()) {
|
|
mEdgeGlowRight.onPullDistance(0f, ev.getY() / getHeight());
|
|
}
|
|
break;
|
|
}
|
|
|
|
case MotionEvent.ACTION_CANCEL:
|
|
case MotionEvent.ACTION_UP:
|
|
/* Release the drag */
|
|
mIsBeingDragged = false;
|
|
mActivePointerId = INVALID_POINTER;
|
|
if (mScroller.springBack(mScrollX, mScrollY, 0, getScrollRange(), 0, 0)) {
|
|
postInvalidateOnAnimation();
|
|
}
|
|
break;
|
|
case MotionEvent.ACTION_POINTER_DOWN: {
|
|
final int index = ev.getActionIndex();
|
|
mLastMotionX = (int) ev.getX(index);
|
|
mActivePointerId = ev.getPointerId(index);
|
|
break;
|
|
}
|
|
case MotionEvent.ACTION_POINTER_UP:
|
|
onSecondaryPointerUp(ev);
|
|
mLastMotionX = (int) ev.getX(ev.findPointerIndex(mActivePointerId));
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* The only time we want to intercept motion events is if we are in the
|
|
* drag mode.
|
|
*/
|
|
return mIsBeingDragged;
|
|
}
|
|
|
|
@Override
|
|
public boolean onTouchEvent(MotionEvent ev) {
|
|
initVelocityTrackerIfNotExists();
|
|
mVelocityTracker.addMovement(ev);
|
|
|
|
final int action = ev.getAction();
|
|
|
|
switch (action & MotionEvent.ACTION_MASK) {
|
|
case MotionEvent.ACTION_DOWN: {
|
|
if (getChildCount() == 0) {
|
|
return false;
|
|
}
|
|
if (!mScroller.isFinished()) {
|
|
final ViewParent parent = getParent();
|
|
if (parent != null) {
|
|
parent.requestDisallowInterceptTouchEvent(true);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* If being flinged and user touches, stop the fling. isFinished
|
|
* will be false if being flinged.
|
|
*/
|
|
if (!mScroller.isFinished()) {
|
|
mScroller.abortAnimation();
|
|
}
|
|
|
|
// Remember where the motion event started
|
|
mLastMotionX = (int) ev.getX();
|
|
mActivePointerId = ev.getPointerId(0);
|
|
break;
|
|
}
|
|
case MotionEvent.ACTION_MOVE:
|
|
final int activePointerIndex = ev.findPointerIndex(mActivePointerId);
|
|
if (activePointerIndex == -1) {
|
|
Log.e(TAG, "Invalid pointerId=" + mActivePointerId + " in onTouchEvent");
|
|
break;
|
|
}
|
|
|
|
final int x = (int) ev.getX(activePointerIndex);
|
|
int deltaX = mLastMotionX - x;
|
|
if (!mIsBeingDragged && Math.abs(deltaX) > mTouchSlop) {
|
|
final ViewParent parent = getParent();
|
|
if (parent != null) {
|
|
parent.requestDisallowInterceptTouchEvent(true);
|
|
}
|
|
mIsBeingDragged = true;
|
|
if (deltaX > 0) {
|
|
deltaX -= mTouchSlop;
|
|
} else {
|
|
deltaX += mTouchSlop;
|
|
}
|
|
}
|
|
if (mIsBeingDragged) {
|
|
// Scroll to follow the motion event
|
|
mLastMotionX = x;
|
|
|
|
final int oldX = mScrollX;
|
|
final int range = getScrollRange();
|
|
final int overscrollMode = getOverScrollMode();
|
|
final boolean canOverscroll = overscrollMode == OVER_SCROLL_ALWAYS ||
|
|
(overscrollMode == OVER_SCROLL_IF_CONTENT_SCROLLS && range > 0);
|
|
|
|
final float displacement = ev.getY(activePointerIndex) / getHeight();
|
|
if (canOverscroll) {
|
|
int consumed = 0;
|
|
if (deltaX < 0 && mEdgeGlowRight.getDistance() != 0f) {
|
|
consumed = Math.round(getWidth()
|
|
* mEdgeGlowRight.onPullDistance((float) deltaX / getWidth(),
|
|
displacement));
|
|
} else if (deltaX > 0 && mEdgeGlowLeft.getDistance() != 0f) {
|
|
consumed = Math.round(-getWidth()
|
|
* mEdgeGlowLeft.onPullDistance((float) -deltaX / getWidth(),
|
|
1 - displacement));
|
|
}
|
|
deltaX -= consumed;
|
|
}
|
|
|
|
// Calling overScrollBy will call onOverScrolled, which
|
|
// calls onScrollChanged if applicable.
|
|
overScrollBy(deltaX, 0, mScrollX, 0, range, 0,
|
|
mOverscrollDistance, 0, true);
|
|
|
|
if (canOverscroll && deltaX != 0f) {
|
|
final int pulledToX = oldX + deltaX;
|
|
if (pulledToX < 0) {
|
|
mEdgeGlowLeft.onPullDistance((float) -deltaX / getWidth(),
|
|
1.f - displacement);
|
|
if (!mEdgeGlowRight.isFinished()) {
|
|
mEdgeGlowRight.onRelease();
|
|
}
|
|
} else if (pulledToX > range) {
|
|
mEdgeGlowRight.onPullDistance((float) deltaX / getWidth(),
|
|
displacement);
|
|
if (!mEdgeGlowLeft.isFinished()) {
|
|
mEdgeGlowLeft.onRelease();
|
|
}
|
|
}
|
|
if (shouldDisplayEdgeEffects()
|
|
&& (!mEdgeGlowLeft.isFinished() || !mEdgeGlowRight.isFinished())) {
|
|
postInvalidateOnAnimation();
|
|
}
|
|
}
|
|
}
|
|
break;
|
|
case MotionEvent.ACTION_UP:
|
|
if (mIsBeingDragged) {
|
|
final VelocityTracker velocityTracker = mVelocityTracker;
|
|
velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity);
|
|
int initialVelocity = (int) velocityTracker.getXVelocity(mActivePointerId);
|
|
|
|
if (getChildCount() > 0) {
|
|
if ((Math.abs(initialVelocity) > mMinimumVelocity)) {
|
|
fling(-initialVelocity);
|
|
} else {
|
|
if (mScroller.springBack(mScrollX, mScrollY, 0,
|
|
getScrollRange(), 0, 0)) {
|
|
postInvalidateOnAnimation();
|
|
}
|
|
}
|
|
}
|
|
|
|
mActivePointerId = INVALID_POINTER;
|
|
mIsBeingDragged = false;
|
|
recycleVelocityTracker();
|
|
|
|
if (shouldDisplayEdgeEffects()) {
|
|
mEdgeGlowLeft.onRelease();
|
|
mEdgeGlowRight.onRelease();
|
|
}
|
|
}
|
|
break;
|
|
case MotionEvent.ACTION_CANCEL:
|
|
if (mIsBeingDragged && getChildCount() > 0) {
|
|
if (mScroller.springBack(mScrollX, mScrollY, 0, getScrollRange(), 0, 0)) {
|
|
postInvalidateOnAnimation();
|
|
}
|
|
mActivePointerId = INVALID_POINTER;
|
|
mIsBeingDragged = false;
|
|
recycleVelocityTracker();
|
|
|
|
if (shouldDisplayEdgeEffects()) {
|
|
mEdgeGlowLeft.onRelease();
|
|
mEdgeGlowRight.onRelease();
|
|
}
|
|
}
|
|
break;
|
|
case MotionEvent.ACTION_POINTER_UP:
|
|
onSecondaryPointerUp(ev);
|
|
break;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
private void onSecondaryPointerUp(MotionEvent ev) {
|
|
final int pointerIndex = (ev.getAction() & MotionEvent.ACTION_POINTER_INDEX_MASK) >>
|
|
MotionEvent.ACTION_POINTER_INDEX_SHIFT;
|
|
final int pointerId = ev.getPointerId(pointerIndex);
|
|
if (pointerId == mActivePointerId) {
|
|
// This was our active pointer going up. Choose a new
|
|
// active pointer and adjust accordingly.
|
|
// TODO: Make this decision more intelligent.
|
|
final int newPointerIndex = pointerIndex == 0 ? 1 : 0;
|
|
mLastMotionX = (int) ev.getX(newPointerIndex);
|
|
mActivePointerId = ev.getPointerId(newPointerIndex);
|
|
if (mVelocityTracker != null) {
|
|
mVelocityTracker.clear();
|
|
}
|
|
}
|
|
}
|
|
|
|
@Override
|
|
public boolean onGenericMotionEvent(MotionEvent event) {
|
|
switch (event.getAction()) {
|
|
case MotionEvent.ACTION_SCROLL: {
|
|
if (!mIsBeingDragged) {
|
|
final float axisValue;
|
|
if (event.isFromSource(InputDevice.SOURCE_CLASS_POINTER)) {
|
|
if ((event.getMetaState() & KeyEvent.META_SHIFT_ON) != 0) {
|
|
axisValue = -event.getAxisValue(MotionEvent.AXIS_VSCROLL);
|
|
} else {
|
|
axisValue = event.getAxisValue(MotionEvent.AXIS_HSCROLL);
|
|
}
|
|
} else if (event.isFromSource(InputDevice.SOURCE_ROTARY_ENCODER)) {
|
|
axisValue = event.getAxisValue(MotionEvent.AXIS_SCROLL);
|
|
} else {
|
|
axisValue = 0;
|
|
}
|
|
|
|
final int delta = Math.round(axisValue * mHorizontalScrollFactor);
|
|
if (delta != 0) {
|
|
final int range = getScrollRange();
|
|
int oldScrollX = mScrollX;
|
|
int newScrollX = oldScrollX + delta;
|
|
|
|
final int overscrollMode = getOverScrollMode();
|
|
boolean canOverscroll = !event.isFromSource(InputDevice.SOURCE_MOUSE)
|
|
&& (overscrollMode == OVER_SCROLL_ALWAYS
|
|
|| (overscrollMode == OVER_SCROLL_IF_CONTENT_SCROLLS && range > 0));
|
|
boolean absorbed = false;
|
|
|
|
if (newScrollX < 0) {
|
|
if (canOverscroll) {
|
|
mEdgeGlowLeft.onPullDistance(-(float) newScrollX / getWidth(),
|
|
0.5f);
|
|
mEdgeGlowLeft.onRelease();
|
|
invalidate();
|
|
absorbed = true;
|
|
}
|
|
newScrollX = 0;
|
|
} else if (newScrollX > range) {
|
|
if (canOverscroll) {
|
|
mEdgeGlowRight.onPullDistance(
|
|
(float) (newScrollX - range) / getWidth(), 0.5f);
|
|
mEdgeGlowRight.onRelease();
|
|
invalidate();
|
|
absorbed = true;
|
|
}
|
|
newScrollX = range;
|
|
}
|
|
if (newScrollX != oldScrollX) {
|
|
super.scrollTo(newScrollX, mScrollY);
|
|
return true;
|
|
}
|
|
if (absorbed) {
|
|
return true;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
return super.onGenericMotionEvent(event);
|
|
}
|
|
|
|
@Override
|
|
public boolean shouldDelayChildPressedState() {
|
|
return true;
|
|
}
|
|
|
|
@Override
|
|
protected void onOverScrolled(int scrollX, int scrollY,
|
|
boolean clampedX, boolean clampedY) {
|
|
// Treat animating scrolls differently; see #computeScroll() for why.
|
|
if (!mScroller.isFinished()) {
|
|
final int oldX = mScrollX;
|
|
final int oldY = mScrollY;
|
|
mScrollX = scrollX;
|
|
mScrollY = scrollY;
|
|
invalidateParentIfNeeded();
|
|
onScrollChanged(mScrollX, mScrollY, oldX, oldY);
|
|
if (clampedX) {
|
|
mScroller.springBack(mScrollX, mScrollY, 0, getScrollRange(), 0, 0);
|
|
}
|
|
} else {
|
|
super.scrollTo(scrollX, scrollY);
|
|
}
|
|
|
|
awakenScrollBars();
|
|
}
|
|
|
|
/** @hide */
|
|
@Override
|
|
public boolean performAccessibilityActionInternal(int action, Bundle arguments) {
|
|
if (super.performAccessibilityActionInternal(action, arguments)) {
|
|
return true;
|
|
}
|
|
switch (action) {
|
|
case AccessibilityNodeInfo.ACTION_SCROLL_FORWARD:
|
|
case R.id.accessibilityActionScrollRight: {
|
|
if (!isEnabled()) {
|
|
return false;
|
|
}
|
|
final int viewportWidth = getWidth() - mPaddingLeft - mPaddingRight;
|
|
final int targetScrollX = Math.min(mScrollX + viewportWidth, getScrollRange());
|
|
if (targetScrollX != mScrollX) {
|
|
smoothScrollTo(targetScrollX, 0);
|
|
return true;
|
|
}
|
|
} return false;
|
|
case AccessibilityNodeInfo.ACTION_SCROLL_BACKWARD:
|
|
case R.id.accessibilityActionScrollLeft: {
|
|
if (!isEnabled()) {
|
|
return false;
|
|
}
|
|
final int viewportWidth = getWidth() - mPaddingLeft - mPaddingRight;
|
|
final int targetScrollX = Math.max(0, mScrollX - viewportWidth);
|
|
if (targetScrollX != mScrollX) {
|
|
smoothScrollTo(targetScrollX, 0);
|
|
return true;
|
|
}
|
|
} return false;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
@Override
|
|
public CharSequence getAccessibilityClassName() {
|
|
return HorizontalScrollView.class.getName();
|
|
}
|
|
|
|
/** @hide */
|
|
@Override
|
|
public void onInitializeAccessibilityNodeInfoInternal(AccessibilityNodeInfo info) {
|
|
super.onInitializeAccessibilityNodeInfoInternal(info);
|
|
final int scrollRange = getScrollRange();
|
|
if (scrollRange > 0) {
|
|
info.setScrollable(true);
|
|
if (isEnabled() && mScrollX > 0) {
|
|
info.addAction(AccessibilityNodeInfo.AccessibilityAction.ACTION_SCROLL_BACKWARD);
|
|
info.addAction(AccessibilityNodeInfo.AccessibilityAction.ACTION_SCROLL_LEFT);
|
|
}
|
|
if (isEnabled() && mScrollX < scrollRange) {
|
|
info.addAction(AccessibilityNodeInfo.AccessibilityAction.ACTION_SCROLL_FORWARD);
|
|
info.addAction(AccessibilityNodeInfo.AccessibilityAction.ACTION_SCROLL_RIGHT);
|
|
}
|
|
}
|
|
}
|
|
|
|
/** @hide */
|
|
@Override
|
|
public void onInitializeAccessibilityEventInternal(AccessibilityEvent event) {
|
|
super.onInitializeAccessibilityEventInternal(event);
|
|
event.setScrollable(getScrollRange() > 0);
|
|
event.setMaxScrollX(getScrollRange());
|
|
event.setMaxScrollY(mScrollY);
|
|
}
|
|
|
|
private int getScrollRange() {
|
|
int scrollRange = 0;
|
|
if (getChildCount() > 0) {
|
|
View child = getChildAt(0);
|
|
scrollRange = Math.max(0,
|
|
child.getWidth() - (getWidth() - mPaddingLeft - mPaddingRight));
|
|
}
|
|
return scrollRange;
|
|
}
|
|
|
|
/**
|
|
* <p>
|
|
* Finds the next focusable component that fits in this View's bounds
|
|
* (excluding fading edges) pretending that this View's left is located at
|
|
* the parameter left.
|
|
* </p>
|
|
*
|
|
* @param leftFocus look for a candidate is the one at the left of the bounds
|
|
* if leftFocus is true, or at the right of the bounds if leftFocus
|
|
* is false
|
|
* @param left the left offset of the bounds in which a focusable must be
|
|
* found (the fading edge is assumed to start at this position)
|
|
* @param preferredFocusable the View that has highest priority and will be
|
|
* returned if it is within my bounds (null is valid)
|
|
* @return the next focusable component in the bounds or null if none can be found
|
|
*/
|
|
private View findFocusableViewInMyBounds(final boolean leftFocus,
|
|
final int left, View preferredFocusable) {
|
|
/*
|
|
* The fading edge's transparent side should be considered for focus
|
|
* since it's mostly visible, so we divide the actual fading edge length
|
|
* by 2.
|
|
*/
|
|
final int fadingEdgeLength = getHorizontalFadingEdgeLength() / 2;
|
|
final int leftWithoutFadingEdge = left + fadingEdgeLength;
|
|
final int rightWithoutFadingEdge = left + getWidth() - fadingEdgeLength;
|
|
|
|
if ((preferredFocusable != null)
|
|
&& (preferredFocusable.getLeft() < rightWithoutFadingEdge)
|
|
&& (preferredFocusable.getRight() > leftWithoutFadingEdge)) {
|
|
return preferredFocusable;
|
|
}
|
|
|
|
return findFocusableViewInBounds(leftFocus, leftWithoutFadingEdge,
|
|
rightWithoutFadingEdge);
|
|
}
|
|
|
|
/**
|
|
* <p>
|
|
* Finds the next focusable component that fits in the specified bounds.
|
|
* </p>
|
|
*
|
|
* @param leftFocus look for a candidate is the one at the left of the bounds
|
|
* if leftFocus is true, or at the right of the bounds if
|
|
* leftFocus is false
|
|
* @param left the left offset of the bounds in which a focusable must be
|
|
* found
|
|
* @param right the right offset of the bounds in which a focusable must
|
|
* be found
|
|
* @return the next focusable component in the bounds or null if none can
|
|
* be found
|
|
*/
|
|
private View findFocusableViewInBounds(boolean leftFocus, int left, int right) {
|
|
|
|
List<View> focusables = getFocusables(View.FOCUS_FORWARD);
|
|
View focusCandidate = null;
|
|
|
|
/*
|
|
* A fully contained focusable is one where its left is below the bound's
|
|
* left, and its right is above the bound's right. A partially
|
|
* contained focusable is one where some part of it is within the
|
|
* bounds, but it also has some part that is not within bounds. A fully contained
|
|
* focusable is preferred to a partially contained focusable.
|
|
*/
|
|
boolean foundFullyContainedFocusable = false;
|
|
|
|
int count = focusables.size();
|
|
for (int i = 0; i < count; i++) {
|
|
View view = focusables.get(i);
|
|
int viewLeft = view.getLeft();
|
|
int viewRight = view.getRight();
|
|
|
|
if (left < viewRight && viewLeft < right) {
|
|
/*
|
|
* the focusable is in the target area, it is a candidate for
|
|
* focusing
|
|
*/
|
|
|
|
final boolean viewIsFullyContained = (left < viewLeft) &&
|
|
(viewRight < right);
|
|
|
|
if (focusCandidate == null) {
|
|
/* No candidate, take this one */
|
|
focusCandidate = view;
|
|
foundFullyContainedFocusable = viewIsFullyContained;
|
|
} else {
|
|
final boolean viewIsCloserToBoundary =
|
|
(leftFocus && viewLeft < focusCandidate.getLeft()) ||
|
|
(!leftFocus && viewRight > focusCandidate.getRight());
|
|
|
|
if (foundFullyContainedFocusable) {
|
|
if (viewIsFullyContained && viewIsCloserToBoundary) {
|
|
/*
|
|
* We're dealing with only fully contained views, so
|
|
* it has to be closer to the boundary to beat our
|
|
* candidate
|
|
*/
|
|
focusCandidate = view;
|
|
}
|
|
} else {
|
|
if (viewIsFullyContained) {
|
|
/* Any fully contained view beats a partially contained view */
|
|
focusCandidate = view;
|
|
foundFullyContainedFocusable = true;
|
|
} else if (viewIsCloserToBoundary) {
|
|
/*
|
|
* Partially contained view beats another partially
|
|
* contained view if it's closer
|
|
*/
|
|
focusCandidate = view;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
return focusCandidate;
|
|
}
|
|
|
|
/**
|
|
* <p>Handles scrolling in response to a "page up/down" shortcut press. This
|
|
* method will scroll the view by one page left or right and give the focus
|
|
* to the leftmost/rightmost component in the new visible area. If no
|
|
* component is a good candidate for focus, this scrollview reclaims the
|
|
* focus.</p>
|
|
*
|
|
* @param direction the scroll direction: {@link android.view.View#FOCUS_LEFT}
|
|
* to go one page left or {@link android.view.View#FOCUS_RIGHT}
|
|
* to go one page right
|
|
* @return true if the key event is consumed by this method, false otherwise
|
|
*/
|
|
public boolean pageScroll(int direction) {
|
|
boolean right = direction == View.FOCUS_RIGHT;
|
|
int width = getWidth();
|
|
|
|
if (right) {
|
|
mTempRect.left = getScrollX() + width;
|
|
int count = getChildCount();
|
|
if (count > 0) {
|
|
View view = getChildAt(0);
|
|
if (mTempRect.left + width > view.getRight()) {
|
|
mTempRect.left = view.getRight() - width;
|
|
}
|
|
}
|
|
} else {
|
|
mTempRect.left = getScrollX() - width;
|
|
if (mTempRect.left < 0) {
|
|
mTempRect.left = 0;
|
|
}
|
|
}
|
|
mTempRect.right = mTempRect.left + width;
|
|
|
|
return scrollAndFocus(direction, mTempRect.left, mTempRect.right);
|
|
}
|
|
|
|
/**
|
|
* <p>Handles scrolling in response to a "home/end" shortcut press. This
|
|
* method will scroll the view to the left or right and give the focus
|
|
* to the leftmost/rightmost component in the new visible area. If no
|
|
* component is a good candidate for focus, this scrollview reclaims the
|
|
* focus.</p>
|
|
*
|
|
* @param direction the scroll direction: {@link android.view.View#FOCUS_LEFT}
|
|
* to go the left of the view or {@link android.view.View#FOCUS_RIGHT}
|
|
* to go the right
|
|
* @return true if the key event is consumed by this method, false otherwise
|
|
*/
|
|
public boolean fullScroll(int direction) {
|
|
boolean right = direction == View.FOCUS_RIGHT;
|
|
int width = getWidth();
|
|
|
|
mTempRect.left = 0;
|
|
mTempRect.right = width;
|
|
|
|
if (right) {
|
|
int count = getChildCount();
|
|
if (count > 0) {
|
|
View view = getChildAt(0);
|
|
mTempRect.right = view.getRight();
|
|
mTempRect.left = mTempRect.right - width;
|
|
}
|
|
}
|
|
|
|
return scrollAndFocus(direction, mTempRect.left, mTempRect.right);
|
|
}
|
|
|
|
/**
|
|
* <p>Scrolls the view to make the area defined by <code>left</code> and
|
|
* <code>right</code> visible. This method attempts to give the focus
|
|
* to a component visible in this area. If no component can be focused in
|
|
* the new visible area, the focus is reclaimed by this scrollview.</p>
|
|
*
|
|
* @param direction the scroll direction: {@link android.view.View#FOCUS_LEFT}
|
|
* to go left {@link android.view.View#FOCUS_RIGHT} to right
|
|
* @param left the left offset of the new area to be made visible
|
|
* @param right the right offset of the new area to be made visible
|
|
* @return true if the key event is consumed by this method, false otherwise
|
|
*/
|
|
private boolean scrollAndFocus(int direction, int left, int right) {
|
|
boolean handled = true;
|
|
|
|
int width = getWidth();
|
|
int containerLeft = getScrollX();
|
|
int containerRight = containerLeft + width;
|
|
boolean goLeft = direction == View.FOCUS_LEFT;
|
|
|
|
View newFocused = findFocusableViewInBounds(goLeft, left, right);
|
|
if (newFocused == null) {
|
|
newFocused = this;
|
|
}
|
|
|
|
if (left >= containerLeft && right <= containerRight) {
|
|
handled = false;
|
|
} else {
|
|
int delta = goLeft ? (left - containerLeft) : (right - containerRight);
|
|
doScrollX(delta);
|
|
}
|
|
|
|
if (newFocused != findFocus()) newFocused.requestFocus(direction);
|
|
|
|
return handled;
|
|
}
|
|
|
|
/**
|
|
* Handle scrolling in response to a left or right arrow click.
|
|
*
|
|
* @param direction The direction corresponding to the arrow key that was
|
|
* pressed
|
|
* @return True if we consumed the event, false otherwise
|
|
*/
|
|
public boolean arrowScroll(int direction) {
|
|
|
|
View currentFocused = findFocus();
|
|
if (currentFocused == this) currentFocused = null;
|
|
|
|
View nextFocused = FocusFinder.getInstance().findNextFocus(this, currentFocused, direction);
|
|
|
|
final int maxJump = getMaxScrollAmount();
|
|
|
|
if (nextFocused != null && isWithinDeltaOfScreen(nextFocused, maxJump)) {
|
|
nextFocused.getDrawingRect(mTempRect);
|
|
offsetDescendantRectToMyCoords(nextFocused, mTempRect);
|
|
int scrollDelta = computeScrollDeltaToGetChildRectOnScreen(mTempRect);
|
|
doScrollX(scrollDelta);
|
|
nextFocused.requestFocus(direction);
|
|
} else {
|
|
// no new focus
|
|
int scrollDelta = maxJump;
|
|
|
|
if (direction == View.FOCUS_LEFT && getScrollX() < scrollDelta) {
|
|
scrollDelta = getScrollX();
|
|
} else if (direction == View.FOCUS_RIGHT && getChildCount() > 0) {
|
|
|
|
int daRight = getChildAt(0).getRight();
|
|
|
|
int screenRight = getScrollX() + getWidth();
|
|
|
|
if (daRight - screenRight < maxJump) {
|
|
scrollDelta = daRight - screenRight;
|
|
}
|
|
}
|
|
if (scrollDelta == 0) {
|
|
return false;
|
|
}
|
|
doScrollX(direction == View.FOCUS_RIGHT ? scrollDelta : -scrollDelta);
|
|
}
|
|
|
|
if (currentFocused != null && currentFocused.isFocused()
|
|
&& isOffScreen(currentFocused)) {
|
|
// previously focused item still has focus and is off screen, give
|
|
// it up (take it back to ourselves)
|
|
// (also, need to temporarily force FOCUS_BEFORE_DESCENDANTS so we are
|
|
// sure to
|
|
// get it)
|
|
final int descendantFocusability = getDescendantFocusability(); // save
|
|
setDescendantFocusability(ViewGroup.FOCUS_BEFORE_DESCENDANTS);
|
|
requestFocus();
|
|
setDescendantFocusability(descendantFocusability); // restore
|
|
}
|
|
return true;
|
|
}
|
|
|
|
/**
|
|
* @return whether the descendant of this scroll view is scrolled off
|
|
* screen.
|
|
*/
|
|
private boolean isOffScreen(View descendant) {
|
|
return !isWithinDeltaOfScreen(descendant, 0);
|
|
}
|
|
|
|
/**
|
|
* @return whether the descendant of this scroll view is within delta
|
|
* pixels of being on the screen.
|
|
*/
|
|
private boolean isWithinDeltaOfScreen(View descendant, int delta) {
|
|
descendant.getDrawingRect(mTempRect);
|
|
offsetDescendantRectToMyCoords(descendant, mTempRect);
|
|
|
|
return (mTempRect.right + delta) >= getScrollX()
|
|
&& (mTempRect.left - delta) <= (getScrollX() + getWidth());
|
|
}
|
|
|
|
/**
|
|
* Smooth scroll by a X delta
|
|
*
|
|
* @param delta the number of pixels to scroll by on the X axis
|
|
*/
|
|
private void doScrollX(int delta) {
|
|
if (delta != 0) {
|
|
if (mSmoothScrollingEnabled) {
|
|
smoothScrollBy(delta, 0);
|
|
} else {
|
|
scrollBy(delta, 0);
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Like {@link View#scrollBy}, but scroll smoothly instead of immediately.
|
|
*
|
|
* @param dx the number of pixels to scroll by on the X axis
|
|
* @param dy the number of pixels to scroll by on the Y axis
|
|
*/
|
|
public final void smoothScrollBy(int dx, int dy) {
|
|
if (getChildCount() == 0) {
|
|
// Nothing to do.
|
|
return;
|
|
}
|
|
long duration = AnimationUtils.currentAnimationTimeMillis() - mLastScroll;
|
|
if (duration > ANIMATED_SCROLL_GAP) {
|
|
final int width = getWidth() - mPaddingRight - mPaddingLeft;
|
|
final int right = getChildAt(0).getWidth();
|
|
final int maxX = Math.max(0, right - width);
|
|
final int scrollX = mScrollX;
|
|
dx = Math.max(0, Math.min(scrollX + dx, maxX)) - scrollX;
|
|
|
|
mScroller.startScroll(scrollX, mScrollY, dx, 0);
|
|
postInvalidateOnAnimation();
|
|
} else {
|
|
if (!mScroller.isFinished()) {
|
|
mScroller.abortAnimation();
|
|
}
|
|
scrollBy(dx, dy);
|
|
}
|
|
mLastScroll = AnimationUtils.currentAnimationTimeMillis();
|
|
}
|
|
|
|
/**
|
|
* Like {@link #scrollTo}, but scroll smoothly instead of immediately.
|
|
*
|
|
* @param x the position where to scroll on the X axis
|
|
* @param y the position where to scroll on the Y axis
|
|
*/
|
|
public final void smoothScrollTo(int x, int y) {
|
|
smoothScrollBy(x - mScrollX, y - mScrollY);
|
|
}
|
|
|
|
/**
|
|
* <p>The scroll range of a scroll view is the overall width of all of its
|
|
* children.</p>
|
|
*/
|
|
@Override
|
|
protected int computeHorizontalScrollRange() {
|
|
final int count = getChildCount();
|
|
final int contentWidth = getWidth() - mPaddingLeft - mPaddingRight;
|
|
if (count == 0) {
|
|
return contentWidth;
|
|
}
|
|
|
|
int scrollRange = getChildAt(0).getRight();
|
|
final int scrollX = mScrollX;
|
|
final int overscrollRight = Math.max(0, scrollRange - contentWidth);
|
|
if (scrollX < 0) {
|
|
scrollRange -= scrollX;
|
|
} else if (scrollX > overscrollRight) {
|
|
scrollRange += scrollX - overscrollRight;
|
|
}
|
|
|
|
return scrollRange;
|
|
}
|
|
|
|
@Override
|
|
protected int computeHorizontalScrollOffset() {
|
|
return Math.max(0, super.computeHorizontalScrollOffset());
|
|
}
|
|
|
|
@Override
|
|
protected void measureChild(View child, int parentWidthMeasureSpec,
|
|
int parentHeightMeasureSpec) {
|
|
ViewGroup.LayoutParams lp = child.getLayoutParams();
|
|
|
|
final int horizontalPadding = mPaddingLeft + mPaddingRight;
|
|
final int childWidthMeasureSpec = MeasureSpec.makeSafeMeasureSpec(
|
|
Math.max(0, MeasureSpec.getSize(parentWidthMeasureSpec) - horizontalPadding),
|
|
MeasureSpec.UNSPECIFIED);
|
|
|
|
final int childHeightMeasureSpec = getChildMeasureSpec(parentHeightMeasureSpec,
|
|
mPaddingTop + mPaddingBottom, lp.height);
|
|
child.measure(childWidthMeasureSpec, childHeightMeasureSpec);
|
|
}
|
|
|
|
@Override
|
|
protected void measureChildWithMargins(View child, int parentWidthMeasureSpec, int widthUsed,
|
|
int parentHeightMeasureSpec, int heightUsed) {
|
|
final MarginLayoutParams lp = (MarginLayoutParams) child.getLayoutParams();
|
|
|
|
final int childHeightMeasureSpec = getChildMeasureSpec(parentHeightMeasureSpec,
|
|
mPaddingTop + mPaddingBottom + lp.topMargin + lp.bottomMargin
|
|
+ heightUsed, lp.height);
|
|
final int usedTotal = mPaddingLeft + mPaddingRight + lp.leftMargin + lp.rightMargin +
|
|
widthUsed;
|
|
final int childWidthMeasureSpec = MeasureSpec.makeSafeMeasureSpec(
|
|
Math.max(0, MeasureSpec.getSize(parentWidthMeasureSpec) - usedTotal),
|
|
MeasureSpec.UNSPECIFIED);
|
|
|
|
child.measure(childWidthMeasureSpec, childHeightMeasureSpec);
|
|
}
|
|
|
|
@Override
|
|
public void computeScroll() {
|
|
if (mScroller.computeScrollOffset()) {
|
|
// This is called at drawing time by ViewGroup. We don't want to
|
|
// re-show the scrollbars at this point, which scrollTo will do,
|
|
// so we replicate most of scrollTo here.
|
|
//
|
|
// It's a little odd to call onScrollChanged from inside the drawing.
|
|
//
|
|
// It is, except when you remember that computeScroll() is used to
|
|
// animate scrolling. So unless we want to defer the onScrollChanged()
|
|
// until the end of the animated scrolling, we don't really have a
|
|
// choice here.
|
|
//
|
|
// I agree. The alternative, which I think would be worse, is to post
|
|
// something and tell the subclasses later. This is bad because there
|
|
// will be a window where mScrollX/Y is different from what the app
|
|
// thinks it is.
|
|
//
|
|
int oldX = mScrollX;
|
|
int oldY = mScrollY;
|
|
int x = mScroller.getCurrX();
|
|
int y = mScroller.getCurrY();
|
|
int deltaX = consumeFlingInStretch(x - oldX);
|
|
|
|
if (deltaX != 0 || oldY != y) {
|
|
final int range = getScrollRange();
|
|
final int overscrollMode = getOverScrollMode();
|
|
final boolean canOverscroll = overscrollMode == OVER_SCROLL_ALWAYS ||
|
|
(overscrollMode == OVER_SCROLL_IF_CONTENT_SCROLLS && range > 0);
|
|
|
|
overScrollBy(deltaX, y - oldY, oldX, oldY, range, 0,
|
|
mOverflingDistance, 0, false);
|
|
onScrollChanged(mScrollX, mScrollY, oldX, oldY);
|
|
|
|
if (canOverscroll && deltaX != 0) {
|
|
if (x < 0 && oldX >= 0) {
|
|
mEdgeGlowLeft.onAbsorb((int) mScroller.getCurrVelocity());
|
|
} else if (x > range && oldX <= range) {
|
|
mEdgeGlowRight.onAbsorb((int) mScroller.getCurrVelocity());
|
|
}
|
|
}
|
|
}
|
|
|
|
if (!awakenScrollBars()) {
|
|
postInvalidateOnAnimation();
|
|
}
|
|
|
|
// For variable refresh rate project to track the current velocity of this View
|
|
if (viewVelocityApi()) {
|
|
setFrameContentVelocity(Math.abs(mScroller.getCurrVelocity()));
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Used by consumeFlingInHorizontalStretch() and consumeFlinInVerticalStretch() for
|
|
* consuming deltas from EdgeEffects
|
|
* @param unconsumed The unconsumed delta that the EdgeEffets may consume
|
|
* @return The unconsumed delta after the EdgeEffects have had an opportunity to consume.
|
|
*/
|
|
private int consumeFlingInStretch(int unconsumed) {
|
|
int scrollX = getScrollX();
|
|
if (scrollX < 0 || scrollX > getScrollRange()) {
|
|
// We've overscrolled, so don't stretch
|
|
return unconsumed;
|
|
}
|
|
if (unconsumed > 0 && mEdgeGlowLeft != null && mEdgeGlowLeft.getDistance() != 0f) {
|
|
int size = getWidth();
|
|
float deltaDistance = -unconsumed * FLING_DESTRETCH_FACTOR / size;
|
|
int consumed = Math.round(-size / FLING_DESTRETCH_FACTOR
|
|
* mEdgeGlowLeft.onPullDistance(deltaDistance, 0.5f));
|
|
if (consumed != unconsumed) {
|
|
mEdgeGlowLeft.finish();
|
|
}
|
|
return unconsumed - consumed;
|
|
}
|
|
if (unconsumed < 0 && mEdgeGlowRight != null && mEdgeGlowRight.getDistance() != 0f) {
|
|
int size = getWidth();
|
|
float deltaDistance = unconsumed * FLING_DESTRETCH_FACTOR / size;
|
|
int consumed = Math.round(size / FLING_DESTRETCH_FACTOR
|
|
* mEdgeGlowRight.onPullDistance(deltaDistance, 0.5f));
|
|
if (consumed != unconsumed) {
|
|
mEdgeGlowRight.finish();
|
|
}
|
|
return unconsumed - consumed;
|
|
}
|
|
return unconsumed;
|
|
}
|
|
|
|
/**
|
|
* Scrolls the view to the given child.
|
|
*
|
|
* @param child the View to scroll to
|
|
*/
|
|
private void scrollToChild(View child) {
|
|
child.getDrawingRect(mTempRect);
|
|
|
|
/* Offset from child's local coordinates to ScrollView coordinates */
|
|
offsetDescendantRectToMyCoords(child, mTempRect);
|
|
|
|
int scrollDelta = computeScrollDeltaToGetChildRectOnScreen(mTempRect);
|
|
|
|
if (scrollDelta != 0) {
|
|
scrollBy(scrollDelta, 0);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* If rect is off screen, scroll just enough to get it (or at least the
|
|
* first screen size chunk of it) on screen.
|
|
*
|
|
* @param rect The rectangle.
|
|
* @param immediate True to scroll immediately without animation
|
|
* @return true if scrolling was performed
|
|
*/
|
|
private boolean scrollToChildRect(Rect rect, boolean immediate) {
|
|
final int delta = computeScrollDeltaToGetChildRectOnScreen(rect);
|
|
final boolean scroll = delta != 0;
|
|
if (scroll) {
|
|
if (immediate) {
|
|
scrollBy(delta, 0);
|
|
} else {
|
|
smoothScrollBy(delta, 0);
|
|
}
|
|
}
|
|
return scroll;
|
|
}
|
|
|
|
/**
|
|
* Compute the amount to scroll in the X direction in order to get
|
|
* a rectangle completely on the screen (or, if taller than the screen,
|
|
* at least the first screen size chunk of it).
|
|
*
|
|
* @param rect The rect.
|
|
* @return The scroll delta.
|
|
*/
|
|
protected int computeScrollDeltaToGetChildRectOnScreen(Rect rect) {
|
|
if (getChildCount() == 0) return 0;
|
|
|
|
int width = getWidth();
|
|
int screenLeft = getScrollX();
|
|
int screenRight = screenLeft + width;
|
|
|
|
int fadingEdge = getHorizontalFadingEdgeLength();
|
|
|
|
// leave room for left fading edge as long as rect isn't at very left
|
|
if (rect.left > 0) {
|
|
screenLeft += fadingEdge;
|
|
}
|
|
|
|
// leave room for right fading edge as long as rect isn't at very right
|
|
if (rect.right < getChildAt(0).getWidth()) {
|
|
screenRight -= fadingEdge;
|
|
}
|
|
|
|
int scrollXDelta = 0;
|
|
|
|
if (rect.right > screenRight && rect.left > screenLeft) {
|
|
// need to move right to get it in view: move right just enough so
|
|
// that the entire rectangle is in view (or at least the first
|
|
// screen size chunk).
|
|
|
|
if (rect.width() > width) {
|
|
// just enough to get screen size chunk on
|
|
scrollXDelta += (rect.left - screenLeft);
|
|
} else {
|
|
// get entire rect at right of screen
|
|
scrollXDelta += (rect.right - screenRight);
|
|
}
|
|
|
|
// make sure we aren't scrolling beyond the end of our content
|
|
int right = getChildAt(0).getRight();
|
|
int distanceToRight = right - screenRight;
|
|
scrollXDelta = Math.min(scrollXDelta, distanceToRight);
|
|
|
|
} else if (rect.left < screenLeft && rect.right < screenRight) {
|
|
// need to move right to get it in view: move right just enough so that
|
|
// entire rectangle is in view (or at least the first screen
|
|
// size chunk of it).
|
|
|
|
if (rect.width() > width) {
|
|
// screen size chunk
|
|
scrollXDelta -= (screenRight - rect.right);
|
|
} else {
|
|
// entire rect at left
|
|
scrollXDelta -= (screenLeft - rect.left);
|
|
}
|
|
|
|
// make sure we aren't scrolling any further than the left our content
|
|
scrollXDelta = Math.max(scrollXDelta, -getScrollX());
|
|
}
|
|
return scrollXDelta;
|
|
}
|
|
|
|
@Override
|
|
public void requestChildFocus(View child, View focused) {
|
|
if (focused != null && focused.getRevealOnFocusHint()) {
|
|
if (!mIsLayoutDirty) {
|
|
scrollToChild(focused);
|
|
} else {
|
|
// The child may not be laid out yet, we can't compute the scroll yet
|
|
mChildToScrollTo = focused;
|
|
}
|
|
}
|
|
super.requestChildFocus(child, focused);
|
|
}
|
|
|
|
|
|
/**
|
|
* When looking for focus in children of a scroll view, need to be a little
|
|
* more careful not to give focus to something that is scrolled off screen.
|
|
*
|
|
* This is more expensive than the default {@link android.view.ViewGroup}
|
|
* implementation, otherwise this behavior might have been made the default.
|
|
*/
|
|
@Override
|
|
protected boolean onRequestFocusInDescendants(int direction,
|
|
Rect previouslyFocusedRect) {
|
|
|
|
// convert from forward / backward notation to up / down / left / right
|
|
// (ugh).
|
|
if (direction == View.FOCUS_FORWARD) {
|
|
direction = View.FOCUS_RIGHT;
|
|
} else if (direction == View.FOCUS_BACKWARD) {
|
|
direction = View.FOCUS_LEFT;
|
|
}
|
|
|
|
final View nextFocus = previouslyFocusedRect == null ?
|
|
FocusFinder.getInstance().findNextFocus(this, null, direction) :
|
|
FocusFinder.getInstance().findNextFocusFromRect(this,
|
|
previouslyFocusedRect, direction);
|
|
|
|
if (nextFocus == null) {
|
|
return false;
|
|
}
|
|
|
|
if (isOffScreen(nextFocus)) {
|
|
return false;
|
|
}
|
|
|
|
return nextFocus.requestFocus(direction, previouslyFocusedRect);
|
|
}
|
|
|
|
@Override
|
|
public boolean requestChildRectangleOnScreen(View child, Rect rectangle,
|
|
boolean immediate) {
|
|
// offset into coordinate space of this scroll view
|
|
rectangle.offset(child.getLeft() - child.getScrollX(),
|
|
child.getTop() - child.getScrollY());
|
|
|
|
return scrollToChildRect(rectangle, immediate);
|
|
}
|
|
|
|
@Override
|
|
public void requestLayout() {
|
|
mIsLayoutDirty = true;
|
|
super.requestLayout();
|
|
}
|
|
|
|
@Override
|
|
protected void onLayout(boolean changed, int l, int t, int r, int b) {
|
|
int childWidth = 0;
|
|
int childMargins = 0;
|
|
|
|
if (getChildCount() > 0) {
|
|
childWidth = getChildAt(0).getMeasuredWidth();
|
|
LayoutParams childParams = (LayoutParams) getChildAt(0).getLayoutParams();
|
|
childMargins = childParams.leftMargin + childParams.rightMargin;
|
|
}
|
|
|
|
final int available = r - l - getPaddingLeftWithForeground() -
|
|
getPaddingRightWithForeground() - childMargins;
|
|
|
|
final boolean forceLeftGravity = (childWidth > available);
|
|
|
|
layoutChildren(l, t, r, b, forceLeftGravity);
|
|
|
|
mIsLayoutDirty = false;
|
|
// Give a child focus if it needs it
|
|
if (mChildToScrollTo != null && isViewDescendantOf(mChildToScrollTo, this)) {
|
|
scrollToChild(mChildToScrollTo);
|
|
}
|
|
mChildToScrollTo = null;
|
|
|
|
if (!isLaidOut()) {
|
|
final int scrollRange = Math.max(0,
|
|
childWidth - (r - l - mPaddingLeft - mPaddingRight));
|
|
if (mSavedState != null) {
|
|
mScrollX = isLayoutRtl()
|
|
? scrollRange - mSavedState.scrollOffsetFromStart
|
|
: mSavedState.scrollOffsetFromStart;
|
|
mSavedState = null;
|
|
} else {
|
|
if (isLayoutRtl()) {
|
|
mScrollX = scrollRange - mScrollX;
|
|
} // mScrollX default value is "0" for LTR
|
|
}
|
|
// Don't forget to clamp
|
|
if (mScrollX > scrollRange) {
|
|
mScrollX = scrollRange;
|
|
} else if (mScrollX < 0) {
|
|
mScrollX = 0;
|
|
}
|
|
}
|
|
|
|
// Calling this with the present values causes it to re-claim them
|
|
scrollTo(mScrollX, mScrollY);
|
|
}
|
|
|
|
@Override
|
|
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
|
|
super.onSizeChanged(w, h, oldw, oldh);
|
|
|
|
View currentFocused = findFocus();
|
|
if (null == currentFocused || this == currentFocused)
|
|
return;
|
|
|
|
final int maxJump = mRight - mLeft;
|
|
|
|
if (isWithinDeltaOfScreen(currentFocused, maxJump)) {
|
|
currentFocused.getDrawingRect(mTempRect);
|
|
offsetDescendantRectToMyCoords(currentFocused, mTempRect);
|
|
int scrollDelta = computeScrollDeltaToGetChildRectOnScreen(mTempRect);
|
|
doScrollX(scrollDelta);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Return true if child is a descendant of parent, (or equal to the parent).
|
|
*/
|
|
private static boolean isViewDescendantOf(View child, View parent) {
|
|
if (child == parent) {
|
|
return true;
|
|
}
|
|
|
|
final ViewParent theParent = child.getParent();
|
|
return (theParent instanceof ViewGroup) && isViewDescendantOf((View) theParent, parent);
|
|
}
|
|
|
|
/**
|
|
* Fling the scroll view
|
|
*
|
|
* @param velocityX The initial velocity in the X direction. Positive
|
|
* numbers mean that the finger/cursor is moving down the screen,
|
|
* which means we want to scroll towards the left.
|
|
*/
|
|
public void fling(int velocityX) {
|
|
if (getChildCount() > 0) {
|
|
int width = getWidth() - mPaddingRight - mPaddingLeft;
|
|
int right = getChildAt(0).getRight() - mPaddingLeft;
|
|
|
|
int maxScroll = Math.max(0, right - width);
|
|
|
|
boolean shouldFling = false;
|
|
if (mScrollX == 0 && !mEdgeGlowLeft.isFinished()) {
|
|
if (shouldAbsorb(mEdgeGlowLeft, -velocityX)) {
|
|
mEdgeGlowLeft.onAbsorb(-velocityX);
|
|
} else {
|
|
shouldFling = true;
|
|
}
|
|
} else if (mScrollX == maxScroll && !mEdgeGlowRight.isFinished()) {
|
|
if (shouldAbsorb(mEdgeGlowRight, velocityX)) {
|
|
mEdgeGlowRight.onAbsorb(velocityX);
|
|
} else {
|
|
shouldFling = true;
|
|
}
|
|
} else {
|
|
shouldFling = true;
|
|
}
|
|
if (shouldFling) {
|
|
mScroller.fling(mScrollX, mScrollY, velocityX, 0, 0,
|
|
maxScroll, 0, 0, width / 2, 0);
|
|
|
|
// For variable refresh rate project to track the current velocity of this View
|
|
if (viewVelocityApi()) {
|
|
setFrameContentVelocity(Math.abs(mScroller.getCurrVelocity()));
|
|
}
|
|
|
|
final boolean movingRight = velocityX > 0;
|
|
|
|
View currentFocused = findFocus();
|
|
View newFocused = findFocusableViewInMyBounds(movingRight,
|
|
mScroller.getFinalX(), currentFocused);
|
|
|
|
if (newFocused == null) {
|
|
newFocused = this;
|
|
}
|
|
|
|
if (newFocused != currentFocused) {
|
|
newFocused.requestFocus(movingRight ? View.FOCUS_RIGHT : View.FOCUS_LEFT);
|
|
}
|
|
}
|
|
|
|
postInvalidateOnAnimation();
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Returns true if edgeEffect should call onAbsorb() with veclocity or false if it should
|
|
* animate with a fling. It will animate with a fling if the velocity will remove the
|
|
* EdgeEffect through its normal operation.
|
|
*
|
|
* @param edgeEffect The EdgeEffect that might absorb the velocity.
|
|
* @param velocity The velocity of the fling motion
|
|
* @return true if the velocity should be absorbed or false if it should be flung.
|
|
*/
|
|
private boolean shouldAbsorb(EdgeEffect edgeEffect, int velocity) {
|
|
if (velocity > 0) {
|
|
return true;
|
|
}
|
|
float distance = edgeEffect.getDistance() * getWidth();
|
|
|
|
// This is flinging without the spring, so let's see if it will fling past the overscroll
|
|
float flingDistance = (float) mScroller.getSplineFlingDistance(-velocity);
|
|
|
|
return flingDistance < distance;
|
|
}
|
|
|
|
/**
|
|
* {@inheritDoc}
|
|
*
|
|
* <p>This version also clamps the scrolling to the bounds of our child.
|
|
*/
|
|
@Override
|
|
public void scrollTo(int x, int y) {
|
|
// we rely on the fact the View.scrollBy calls scrollTo.
|
|
if (getChildCount() > 0) {
|
|
View child = getChildAt(0);
|
|
x = clamp(x, getWidth() - mPaddingRight - mPaddingLeft, child.getWidth());
|
|
y = clamp(y, getHeight() - mPaddingBottom - mPaddingTop, child.getHeight());
|
|
if (x != mScrollX || y != mScrollY) {
|
|
super.scrollTo(x, y);
|
|
}
|
|
}
|
|
}
|
|
|
|
private boolean shouldDisplayEdgeEffects() {
|
|
return getOverScrollMode() != OVER_SCROLL_NEVER;
|
|
}
|
|
|
|
@SuppressWarnings({"SuspiciousNameCombination"})
|
|
@Override
|
|
public void draw(Canvas canvas) {
|
|
super.draw(canvas);
|
|
if (shouldDisplayEdgeEffects()) {
|
|
final int scrollX = mScrollX;
|
|
if (!mEdgeGlowLeft.isFinished()) {
|
|
final int restoreCount = canvas.save();
|
|
final int height = getHeight() - mPaddingTop - mPaddingBottom;
|
|
|
|
canvas.rotate(270);
|
|
canvas.translate(-height + mPaddingTop, Math.min(0, scrollX));
|
|
mEdgeGlowLeft.setSize(height, getWidth());
|
|
if (mEdgeGlowLeft.draw(canvas)) {
|
|
postInvalidateOnAnimation();
|
|
}
|
|
canvas.restoreToCount(restoreCount);
|
|
}
|
|
if (!mEdgeGlowRight.isFinished()) {
|
|
final int restoreCount = canvas.save();
|
|
final int width = getWidth();
|
|
final int height = getHeight() - mPaddingTop - mPaddingBottom;
|
|
|
|
canvas.rotate(90);
|
|
canvas.translate(-mPaddingTop,
|
|
-(Math.max(getScrollRange(), scrollX) + width));
|
|
mEdgeGlowRight.setSize(height, width);
|
|
if (mEdgeGlowRight.draw(canvas)) {
|
|
postInvalidateOnAnimation();
|
|
}
|
|
canvas.restoreToCount(restoreCount);
|
|
}
|
|
}
|
|
}
|
|
|
|
private static int clamp(int n, int my, int child) {
|
|
if (my >= child || n < 0) {
|
|
return 0;
|
|
}
|
|
if ((my + n) > child) {
|
|
return child - my;
|
|
}
|
|
return n;
|
|
}
|
|
|
|
@Override
|
|
protected void onRestoreInstanceState(Parcelable state) {
|
|
if (mContext.getApplicationInfo().targetSdkVersion <= Build.VERSION_CODES.JELLY_BEAN_MR2) {
|
|
// Some old apps reused IDs in ways they shouldn't have.
|
|
// Don't break them, but they don't get scroll state restoration.
|
|
super.onRestoreInstanceState(state);
|
|
return;
|
|
}
|
|
SavedState ss = (SavedState) state;
|
|
super.onRestoreInstanceState(ss.getSuperState());
|
|
mSavedState = ss;
|
|
requestLayout();
|
|
}
|
|
|
|
@Override
|
|
protected Parcelable onSaveInstanceState() {
|
|
if (mContext.getApplicationInfo().targetSdkVersion <= Build.VERSION_CODES.JELLY_BEAN_MR2) {
|
|
// Some old apps reused IDs in ways they shouldn't have.
|
|
// Don't break them, but they don't get scroll state restoration.
|
|
return super.onSaveInstanceState();
|
|
}
|
|
Parcelable superState = super.onSaveInstanceState();
|
|
SavedState ss = new SavedState(superState);
|
|
ss.scrollOffsetFromStart = isLayoutRtl() ? -mScrollX : mScrollX;
|
|
return ss;
|
|
}
|
|
|
|
/** @hide */
|
|
@Override
|
|
protected void encodeProperties(@NonNull ViewHierarchyEncoder encoder) {
|
|
super.encodeProperties(encoder);
|
|
encoder.addProperty("layout:fillViewPort", mFillViewport);
|
|
}
|
|
|
|
static class SavedState extends BaseSavedState {
|
|
public int scrollOffsetFromStart;
|
|
|
|
SavedState(Parcelable superState) {
|
|
super(superState);
|
|
}
|
|
|
|
public SavedState(Parcel source) {
|
|
super(source);
|
|
scrollOffsetFromStart = source.readInt();
|
|
}
|
|
|
|
@Override
|
|
public void writeToParcel(Parcel dest, int flags) {
|
|
super.writeToParcel(dest, flags);
|
|
dest.writeInt(scrollOffsetFromStart);
|
|
}
|
|
|
|
@Override
|
|
public String toString() {
|
|
return "HorizontalScrollView.SavedState{"
|
|
+ Integer.toHexString(System.identityHashCode(this))
|
|
+ " scrollPosition=" + scrollOffsetFromStart
|
|
+ "}";
|
|
}
|
|
|
|
public static final @android.annotation.NonNull Parcelable.Creator<SavedState> CREATOR
|
|
= new Parcelable.Creator<SavedState>() {
|
|
public SavedState createFromParcel(Parcel in) {
|
|
return new SavedState(in);
|
|
}
|
|
|
|
public SavedState[] newArray(int size) {
|
|
return new SavedState[size];
|
|
}
|
|
};
|
|
}
|
|
}
|