911 lines
37 KiB
Java
911 lines
37 KiB
Java
/*
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* Copyright (C) 2010 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.app;
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import android.content.Loader;
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import android.os.Bundle;
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import android.util.DebugUtils;
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import android.util.Log;
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import android.util.SparseArray;
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import java.io.FileDescriptor;
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import java.io.PrintWriter;
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import java.lang.reflect.Modifier;
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/**
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* Interface associated with an {@link Activity} or {@link Fragment} for managing
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* one or more {@link android.content.Loader} instances associated with it. This
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* helps an application manage longer-running operations in conjunction with the
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* Activity or Fragment lifecycle; the most common use of this is with a
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* {@link android.content.CursorLoader}, however applications are free to write
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* their own loaders for loading other types of data.
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*
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* While the LoaderManager API was introduced in
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* {@link android.os.Build.VERSION_CODES#HONEYCOMB}, a version of the API
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* at is also available for use on older platforms through
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* {@link androidx.fragment.app.FragmentActivity}. See the blog post
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* <a href="http://android-developers.blogspot.com/2011/03/fragments-for-all.html">
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* Fragments For All</a> for more details.
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*
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* <p>As an example, here is the full implementation of a {@link Fragment}
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* that displays a {@link android.widget.ListView} containing the results of
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* a query against the contacts content provider. It uses a
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* {@link android.content.CursorLoader} to manage the query on the provider.
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*
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* {@sample development/samples/ApiDemos/src/com/example/android/apis/app/LoaderCursor.java
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* fragment_cursor}
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*
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* <div class="special reference">
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* <h3>Developer Guides</h3>
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* <p>For more information about using loaders, read the
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* <a href="{@docRoot}guide/topics/fundamentals/loaders.html">Loaders</a> developer guide.</p>
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* </div>
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*
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* @deprecated Use the <a href="{@docRoot}tools/extras/support-library.html">Support Library</a>
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* {@link androidx.loader.app.LoaderManager}
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*/
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@Deprecated
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public abstract class LoaderManager {
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/**
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* Callback interface for a client to interact with the manager.
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*
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* @deprecated Use the <a href="{@docRoot}tools/extras/support-library.html">
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* Support Library</a> {@link androidx.loader.app.LoaderManager.LoaderCallbacks}
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*/
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@Deprecated
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public interface LoaderCallbacks<D> {
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/**
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* Instantiate and return a new Loader for the given ID.
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*
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* @param id The ID whose loader is to be created.
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* @param args Any arguments supplied by the caller.
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* @return Return a new Loader instance that is ready to start loading.
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*/
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public Loader<D> onCreateLoader(int id, Bundle args);
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/**
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* Called when a previously created loader has finished its load. Note
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* that normally an application is <em>not</em> allowed to commit fragment
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* transactions while in this call, since it can happen after an
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* activity's state is saved. See {@link FragmentManager#beginTransaction()
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* FragmentManager.openTransaction()} for further discussion on this.
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*
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* <p>This function is guaranteed to be called prior to the release of
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* the last data that was supplied for this Loader. At this point
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* you should remove all use of the old data (since it will be released
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* soon), but should not do your own release of the data since its Loader
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* owns it and will take care of that. The Loader will take care of
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* management of its data so you don't have to. In particular:
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*
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* <ul>
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* <li> <p>The Loader will monitor for changes to the data, and report
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* them to you through new calls here. You should not monitor the
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* data yourself. For example, if the data is a {@link android.database.Cursor}
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* and you place it in a {@link android.widget.CursorAdapter}, use
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* the {@link android.widget.CursorAdapter#CursorAdapter(android.content.Context,
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* android.database.Cursor, int)} constructor <em>without</em> passing
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* in either {@link android.widget.CursorAdapter#FLAG_AUTO_REQUERY}
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* or {@link android.widget.CursorAdapter#FLAG_REGISTER_CONTENT_OBSERVER}
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* (that is, use 0 for the flags argument). This prevents the CursorAdapter
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* from doing its own observing of the Cursor, which is not needed since
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* when a change happens you will get a new Cursor throw another call
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* here.
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* <li> The Loader will release the data once it knows the application
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* is no longer using it. For example, if the data is
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* a {@link android.database.Cursor} from a {@link android.content.CursorLoader},
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* you should not call close() on it yourself. If the Cursor is being placed in a
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* {@link android.widget.CursorAdapter}, you should use the
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* {@link android.widget.CursorAdapter#swapCursor(android.database.Cursor)}
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* method so that the old Cursor is not closed.
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* </ul>
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*
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* @param loader The Loader that has finished.
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* @param data The data generated by the Loader.
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*/
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public void onLoadFinished(Loader<D> loader, D data);
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/**
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* Called when a previously created loader is being reset, and thus
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* making its data unavailable. The application should at this point
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* remove any references it has to the Loader's data.
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*
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* @param loader The Loader that is being reset.
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*/
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public void onLoaderReset(Loader<D> loader);
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}
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/**
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* Ensures a loader is initialized and active. If the loader doesn't
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* already exist, one is created and (if the activity/fragment is currently
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* started) starts the loader. Otherwise the last created
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* loader is re-used.
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*
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* <p>In either case, the given callback is associated with the loader, and
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* will be called as the loader state changes. If at the point of call
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* the caller is in its started state, and the requested loader
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* already exists and has generated its data, then
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* callback {@link LoaderCallbacks#onLoadFinished} will
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* be called immediately (inside of this function), so you must be prepared
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* for this to happen.
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*
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* @param id A unique identifier for this loader. Can be whatever you want.
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* Identifiers are scoped to a particular LoaderManager instance.
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* @param args Optional arguments to supply to the loader at construction.
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* If a loader already exists (a new one does not need to be created), this
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* parameter will be ignored and the last arguments continue to be used.
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* @param callback Interface the LoaderManager will call to report about
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* changes in the state of the loader. Required.
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*/
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public abstract <D> Loader<D> initLoader(int id, Bundle args,
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LoaderManager.LoaderCallbacks<D> callback);
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/**
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* Starts a new or restarts an existing {@link android.content.Loader} in
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* this manager, registers the callbacks to it,
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* and (if the activity/fragment is currently started) starts loading it.
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* If a loader with the same id has previously been
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* started it will automatically be destroyed when the new loader completes
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* its work. The callback will be delivered before the old loader
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* is destroyed.
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*
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* @param id A unique identifier for this loader. Can be whatever you want.
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* Identifiers are scoped to a particular LoaderManager instance.
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* @param args Optional arguments to supply to the loader at construction.
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* @param callback Interface the LoaderManager will call to report about
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* changes in the state of the loader. Required.
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*/
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public abstract <D> Loader<D> restartLoader(int id, Bundle args,
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LoaderManager.LoaderCallbacks<D> callback);
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/**
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* Stops and removes the loader with the given ID. If this loader
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* had previously reported data to the client through
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* {@link LoaderCallbacks#onLoadFinished(Loader, Object)}, a call
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* will be made to {@link LoaderCallbacks#onLoaderReset(Loader)}.
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*/
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public abstract void destroyLoader(int id);
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/**
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* Return the Loader with the given id or null if no matching Loader
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* is found.
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*/
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public abstract <D> Loader<D> getLoader(int id);
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/**
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* Print the LoaderManager's state into the given stream.
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*
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* @param prefix Text to print at the front of each line.
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* @param fd The raw file descriptor that the dump is being sent to.
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* @param writer A PrintWriter to which the dump is to be set.
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* @param args Additional arguments to the dump request.
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*/
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public abstract void dump(String prefix, FileDescriptor fd, PrintWriter writer, String[] args);
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/**
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* Control whether the framework's internal loader manager debugging
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* logs are turned on. If enabled, you will see output in logcat as
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* the framework performs loader operations.
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*/
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public static void enableDebugLogging(boolean enabled) {
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LoaderManagerImpl.DEBUG = enabled;
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}
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/** @hide for internal testing only */
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public FragmentHostCallback getFragmentHostCallback() { return null; }
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}
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class LoaderManagerImpl extends LoaderManager {
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static final String TAG = "LoaderManager";
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static boolean DEBUG = false;
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// These are the currently active loaders. A loader is here
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// from the time its load is started until it has been explicitly
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// stopped or restarted by the application.
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final SparseArray<LoaderInfo> mLoaders = new SparseArray<LoaderInfo>(0);
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// These are previously run loaders. This list is maintained internally
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// to avoid destroying a loader while an application is still using it.
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// It allows an application to restart a loader, but continue using its
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// previously run loader until the new loader's data is available.
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final SparseArray<LoaderInfo> mInactiveLoaders = new SparseArray<LoaderInfo>(0);
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final String mWho;
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boolean mStarted;
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boolean mRetaining;
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boolean mRetainingStarted;
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boolean mCreatingLoader;
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private FragmentHostCallback mHost;
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final class LoaderInfo implements Loader.OnLoadCompleteListener<Object>,
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Loader.OnLoadCanceledListener<Object> {
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final int mId;
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final Bundle mArgs;
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LoaderManager.LoaderCallbacks<Object> mCallbacks;
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Loader<Object> mLoader;
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boolean mHaveData;
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boolean mDeliveredData;
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Object mData;
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boolean mStarted;
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boolean mRetaining;
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boolean mRetainingStarted;
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boolean mReportNextStart;
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boolean mDestroyed;
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boolean mListenerRegistered;
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LoaderInfo mPendingLoader;
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public LoaderInfo(int id, Bundle args, LoaderManager.LoaderCallbacks<Object> callbacks) {
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mId = id;
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mArgs = args;
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mCallbacks = callbacks;
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}
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void start() {
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if (mRetaining && mRetainingStarted) {
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// Our owner is started, but we were being retained from a
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// previous instance in the started state... so there is really
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// nothing to do here, since the loaders are still started.
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mStarted = true;
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return;
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}
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if (mStarted) {
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// If loader already started, don't restart.
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return;
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}
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mStarted = true;
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if (DEBUG) Log.v(TAG, " Starting: " + this);
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if (mLoader == null && mCallbacks != null) {
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mLoader = mCallbacks.onCreateLoader(mId, mArgs);
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}
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if (mLoader != null) {
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if (mLoader.getClass().isMemberClass()
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&& !Modifier.isStatic(mLoader.getClass().getModifiers())) {
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throw new IllegalArgumentException(
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"Object returned from onCreateLoader must not be a non-static inner member class: "
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+ mLoader);
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}
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if (!mListenerRegistered) {
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mLoader.registerListener(mId, this);
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mLoader.registerOnLoadCanceledListener(this);
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mListenerRegistered = true;
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}
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mLoader.startLoading();
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}
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}
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void retain() {
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if (DEBUG) Log.v(TAG, " Retaining: " + this);
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mRetaining = true;
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mRetainingStarted = mStarted;
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mStarted = false;
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mCallbacks = null;
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}
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void finishRetain() {
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if (mRetaining) {
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if (DEBUG) Log.v(TAG, " Finished Retaining: " + this);
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mRetaining = false;
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if (mStarted != mRetainingStarted) {
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if (!mStarted) {
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// This loader was retained in a started state, but
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// at the end of retaining everything our owner is
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// no longer started... so make it stop.
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stop();
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}
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}
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}
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if (mStarted && mHaveData && !mReportNextStart) {
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// This loader has retained its data, either completely across
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// a configuration change or just whatever the last data set
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// was after being restarted from a stop, and now at the point of
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// finishing the retain we find we remain started, have
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// our data, and the owner has a new callback... so
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// let's deliver the data now.
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callOnLoadFinished(mLoader, mData);
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}
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}
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void reportStart() {
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if (mStarted) {
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if (mReportNextStart) {
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mReportNextStart = false;
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if (mHaveData && !mRetaining) {
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callOnLoadFinished(mLoader, mData);
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}
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}
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}
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}
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void stop() {
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if (DEBUG) Log.v(TAG, " Stopping: " + this);
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mStarted = false;
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if (!mRetaining) {
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if (mLoader != null && mListenerRegistered) {
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// Let the loader know we're done with it
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mListenerRegistered = false;
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mLoader.unregisterListener(this);
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mLoader.unregisterOnLoadCanceledListener(this);
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mLoader.stopLoading();
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}
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}
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}
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boolean cancel() {
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if (DEBUG) Log.v(TAG, " Canceling: " + this);
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if (mStarted && mLoader != null && mListenerRegistered) {
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final boolean cancelLoadResult = mLoader.cancelLoad();
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if (!cancelLoadResult) {
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onLoadCanceled(mLoader);
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}
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return cancelLoadResult;
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}
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return false;
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}
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void destroy() {
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if (DEBUG) Log.v(TAG, " Destroying: " + this);
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mDestroyed = true;
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boolean needReset = mDeliveredData;
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mDeliveredData = false;
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if (mCallbacks != null && mLoader != null && mHaveData && needReset) {
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if (DEBUG) Log.v(TAG, " Reseting: " + this);
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String lastBecause = null;
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if (mHost != null) {
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lastBecause = mHost.mFragmentManager.mNoTransactionsBecause;
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mHost.mFragmentManager.mNoTransactionsBecause = "onLoaderReset";
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}
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try {
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mCallbacks.onLoaderReset(mLoader);
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} finally {
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if (mHost != null) {
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mHost.mFragmentManager.mNoTransactionsBecause = lastBecause;
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}
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}
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}
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mCallbacks = null;
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mData = null;
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mHaveData = false;
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if (mLoader != null) {
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if (mListenerRegistered) {
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mListenerRegistered = false;
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mLoader.unregisterListener(this);
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mLoader.unregisterOnLoadCanceledListener(this);
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}
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mLoader.reset();
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}
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if (mPendingLoader != null) {
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mPendingLoader.destroy();
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}
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}
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@Override
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public void onLoadCanceled(Loader<Object> loader) {
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if (DEBUG) Log.v(TAG, "onLoadCanceled: " + this);
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if (mDestroyed) {
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if (DEBUG) Log.v(TAG, " Ignoring load canceled -- destroyed");
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return;
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}
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if (mLoaders.get(mId) != this) {
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// This cancellation message is not coming from the current active loader.
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// We don't care about it.
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if (DEBUG) Log.v(TAG, " Ignoring load canceled -- not active");
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return;
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}
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LoaderInfo pending = mPendingLoader;
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if (pending != null) {
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// There is a new request pending and we were just
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// waiting for the old one to cancel or complete before starting
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// it. So now it is time, switch over to the new loader.
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if (DEBUG) Log.v(TAG, " Switching to pending loader: " + pending);
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mPendingLoader = null;
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mLoaders.put(mId, null);
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destroy();
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installLoader(pending);
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}
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}
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@Override
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public void onLoadComplete(Loader<Object> loader, Object data) {
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if (DEBUG) Log.v(TAG, "onLoadComplete: " + this);
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if (mDestroyed) {
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if (DEBUG) Log.v(TAG, " Ignoring load complete -- destroyed");
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return;
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}
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if (mLoaders.get(mId) != this) {
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// This data is not coming from the current active loader.
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// We don't care about it.
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if (DEBUG) Log.v(TAG, " Ignoring load complete -- not active");
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return;
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}
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LoaderInfo pending = mPendingLoader;
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if (pending != null) {
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// There is a new request pending and we were just
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// waiting for the old one to complete before starting
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// it. So now it is time, switch over to the new loader.
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if (DEBUG) Log.v(TAG, " Switching to pending loader: " + pending);
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mPendingLoader = null;
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mLoaders.put(mId, null);
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destroy();
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installLoader(pending);
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return;
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}
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// Notify of the new data so the app can switch out the old data before
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// we try to destroy it.
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if (mData != data || !mHaveData) {
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mData = data;
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mHaveData = true;
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if (mStarted) {
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callOnLoadFinished(loader, data);
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}
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}
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//if (DEBUG) Log.v(TAG, " onLoadFinished returned: " + this);
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// We have now given the application the new loader with its
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// loaded data, so it should have stopped using the previous
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// loader. If there is a previous loader on the inactive list,
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// clean it up.
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LoaderInfo info = mInactiveLoaders.get(mId);
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if (info != null && info != this) {
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info.mDeliveredData = false;
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info.destroy();
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mInactiveLoaders.remove(mId);
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}
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if (mHost != null && !hasRunningLoaders()) {
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mHost.mFragmentManager.startPendingDeferredFragments();
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}
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}
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void callOnLoadFinished(Loader<Object> loader, Object data) {
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if (mCallbacks != null) {
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String lastBecause = null;
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if (mHost != null) {
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lastBecause = mHost.mFragmentManager.mNoTransactionsBecause;
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mHost.mFragmentManager.mNoTransactionsBecause = "onLoadFinished";
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}
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try {
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if (DEBUG) Log.v(TAG, " onLoadFinished in " + loader + ": "
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+ loader.dataToString(data));
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|
mCallbacks.onLoadFinished(loader, data);
|
|
} finally {
|
|
if (mHost != null) {
|
|
mHost.mFragmentManager.mNoTransactionsBecause = lastBecause;
|
|
}
|
|
}
|
|
mDeliveredData = true;
|
|
}
|
|
}
|
|
|
|
@Override
|
|
public String toString() {
|
|
StringBuilder sb = new StringBuilder(64);
|
|
sb.append("LoaderInfo{");
|
|
sb.append(Integer.toHexString(System.identityHashCode(this)));
|
|
sb.append(" #");
|
|
sb.append(mId);
|
|
sb.append(" : ");
|
|
DebugUtils.buildShortClassTag(mLoader, sb);
|
|
sb.append("}}");
|
|
return sb.toString();
|
|
}
|
|
|
|
public void dump(String prefix, FileDescriptor fd, PrintWriter writer, String[] args) {
|
|
writer.print(prefix); writer.print("mId="); writer.print(mId);
|
|
writer.print(" mArgs="); writer.println(mArgs);
|
|
writer.print(prefix); writer.print("mCallbacks="); writer.println(mCallbacks);
|
|
writer.print(prefix); writer.print("mLoader="); writer.println(mLoader);
|
|
if (mLoader != null) {
|
|
mLoader.dump(prefix + " ", fd, writer, args);
|
|
}
|
|
if (mHaveData || mDeliveredData) {
|
|
writer.print(prefix); writer.print("mHaveData="); writer.print(mHaveData);
|
|
writer.print(" mDeliveredData="); writer.println(mDeliveredData);
|
|
writer.print(prefix); writer.print("mData="); writer.println(mData);
|
|
}
|
|
writer.print(prefix); writer.print("mStarted="); writer.print(mStarted);
|
|
writer.print(" mReportNextStart="); writer.print(mReportNextStart);
|
|
writer.print(" mDestroyed="); writer.println(mDestroyed);
|
|
writer.print(prefix); writer.print("mRetaining="); writer.print(mRetaining);
|
|
writer.print(" mRetainingStarted="); writer.print(mRetainingStarted);
|
|
writer.print(" mListenerRegistered="); writer.println(mListenerRegistered);
|
|
if (mPendingLoader != null) {
|
|
writer.print(prefix); writer.println("Pending Loader ");
|
|
writer.print(mPendingLoader); writer.println(":");
|
|
mPendingLoader.dump(prefix + " ", fd, writer, args);
|
|
}
|
|
}
|
|
}
|
|
|
|
LoaderManagerImpl(String who, FragmentHostCallback host, boolean started) {
|
|
mWho = who;
|
|
mHost = host;
|
|
mStarted = started;
|
|
}
|
|
|
|
void updateHostController(FragmentHostCallback host) {
|
|
mHost = host;
|
|
}
|
|
|
|
public FragmentHostCallback getFragmentHostCallback() {
|
|
return mHost;
|
|
}
|
|
|
|
private LoaderInfo createLoader(int id, Bundle args,
|
|
LoaderManager.LoaderCallbacks<Object> callback) {
|
|
LoaderInfo info = new LoaderInfo(id, args, (LoaderManager.LoaderCallbacks<Object>)callback);
|
|
Loader<Object> loader = callback.onCreateLoader(id, args);
|
|
info.mLoader = (Loader<Object>)loader;
|
|
return info;
|
|
}
|
|
|
|
private LoaderInfo createAndInstallLoader(int id, Bundle args,
|
|
LoaderManager.LoaderCallbacks<Object> callback) {
|
|
try {
|
|
mCreatingLoader = true;
|
|
LoaderInfo info = createLoader(id, args, callback);
|
|
installLoader(info);
|
|
return info;
|
|
} finally {
|
|
mCreatingLoader = false;
|
|
}
|
|
}
|
|
|
|
void installLoader(LoaderInfo info) {
|
|
mLoaders.put(info.mId, info);
|
|
if (mStarted) {
|
|
// The activity will start all existing loaders in it's onStart(),
|
|
// so only start them here if we're past that point of the activitiy's
|
|
// life cycle
|
|
info.start();
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Call to initialize a particular ID with a Loader. If this ID already
|
|
* has a Loader associated with it, it is left unchanged and any previous
|
|
* callbacks replaced with the newly provided ones. If there is not currently
|
|
* a Loader for the ID, a new one is created and started.
|
|
*
|
|
* <p>This function should generally be used when a component is initializing,
|
|
* to ensure that a Loader it relies on is created. This allows it to re-use
|
|
* an existing Loader's data if there already is one, so that for example
|
|
* when an {@link Activity} is re-created after a configuration change it
|
|
* does not need to re-create its loaders.
|
|
*
|
|
* <p>Note that in the case where an existing Loader is re-used, the
|
|
* <var>args</var> given here <em>will be ignored</em> because you will
|
|
* continue using the previous Loader.
|
|
*
|
|
* @param id A unique (to this LoaderManager instance) identifier under
|
|
* which to manage the new Loader.
|
|
* @param args Optional arguments that will be propagated to
|
|
* {@link LoaderCallbacks#onCreateLoader(int, Bundle) LoaderCallbacks.onCreateLoader()}.
|
|
* @param callback Interface implementing management of this Loader. Required.
|
|
* Its onCreateLoader() method will be called while inside of the function to
|
|
* instantiate the Loader object.
|
|
*/
|
|
@SuppressWarnings("unchecked")
|
|
public <D> Loader<D> initLoader(int id, Bundle args, LoaderManager.LoaderCallbacks<D> callback) {
|
|
if (mCreatingLoader) {
|
|
throw new IllegalStateException("Called while creating a loader");
|
|
}
|
|
|
|
LoaderInfo info = mLoaders.get(id);
|
|
|
|
if (DEBUG) Log.v(TAG, "initLoader in " + this + ": args=" + args);
|
|
|
|
if (info == null) {
|
|
// Loader doesn't already exist; create.
|
|
info = createAndInstallLoader(id, args, (LoaderManager.LoaderCallbacks<Object>)callback);
|
|
if (DEBUG) Log.v(TAG, " Created new loader " + info);
|
|
} else {
|
|
if (DEBUG) Log.v(TAG, " Re-using existing loader " + info);
|
|
info.mCallbacks = (LoaderManager.LoaderCallbacks<Object>)callback;
|
|
}
|
|
|
|
if (info.mHaveData && mStarted) {
|
|
// If the loader has already generated its data, report it now.
|
|
info.callOnLoadFinished(info.mLoader, info.mData);
|
|
}
|
|
|
|
return (Loader<D>)info.mLoader;
|
|
}
|
|
|
|
/**
|
|
* Call to re-create the Loader associated with a particular ID. If there
|
|
* is currently a Loader associated with this ID, it will be
|
|
* canceled/stopped/destroyed as appropriate. A new Loader with the given
|
|
* arguments will be created and its data delivered to you once available.
|
|
*
|
|
* <p>This function does some throttling of Loaders. If too many Loaders
|
|
* have been created for the given ID but not yet generated their data,
|
|
* new calls to this function will create and return a new Loader but not
|
|
* actually start it until some previous loaders have completed.
|
|
*
|
|
* <p>After calling this function, any previous Loaders associated with
|
|
* this ID will be considered invalid, and you will receive no further
|
|
* data updates from them.
|
|
*
|
|
* @param id A unique (to this LoaderManager instance) identifier under
|
|
* which to manage the new Loader.
|
|
* @param args Optional arguments that will be propagated to
|
|
* {@link LoaderCallbacks#onCreateLoader(int, Bundle) LoaderCallbacks.onCreateLoader()}.
|
|
* @param callback Interface implementing management of this Loader. Required.
|
|
* Its onCreateLoader() method will be called while inside of the function to
|
|
* instantiate the Loader object.
|
|
*/
|
|
@SuppressWarnings("unchecked")
|
|
public <D> Loader<D> restartLoader(int id, Bundle args, LoaderManager.LoaderCallbacks<D> callback) {
|
|
if (mCreatingLoader) {
|
|
throw new IllegalStateException("Called while creating a loader");
|
|
}
|
|
|
|
LoaderInfo info = mLoaders.get(id);
|
|
if (DEBUG) Log.v(TAG, "restartLoader in " + this + ": args=" + args);
|
|
if (info != null) {
|
|
LoaderInfo inactive = mInactiveLoaders.get(id);
|
|
if (inactive != null) {
|
|
if (info.mHaveData) {
|
|
// This loader now has data... we are probably being
|
|
// called from within onLoadComplete, where we haven't
|
|
// yet destroyed the last inactive loader. So just do
|
|
// that now.
|
|
if (DEBUG) Log.v(TAG, " Removing last inactive loader: " + info);
|
|
inactive.mDeliveredData = false;
|
|
inactive.destroy();
|
|
info.mLoader.abandon();
|
|
mInactiveLoaders.put(id, info);
|
|
} else {
|
|
// We already have an inactive loader for this ID that we are
|
|
// waiting for! Try to cancel; if this returns true then the task is still
|
|
// running and we have more work to do.
|
|
if (!info.cancel()) {
|
|
// The current Loader has not been started or was successfully canceled,
|
|
// we thus have no reason to keep it around. Remove it and a new
|
|
// LoaderInfo will be created below.
|
|
if (DEBUG) Log.v(TAG, " Current loader is stopped; replacing");
|
|
mLoaders.put(id, null);
|
|
info.destroy();
|
|
} else {
|
|
// Now we have three active loaders... we'll queue
|
|
// up this request to be processed once one of the other loaders
|
|
// finishes.
|
|
if (DEBUG) Log.v(TAG,
|
|
" Current loader is running; configuring pending loader");
|
|
if (info.mPendingLoader != null) {
|
|
if (DEBUG) Log.v(TAG, " Removing pending loader: " + info.mPendingLoader);
|
|
info.mPendingLoader.destroy();
|
|
info.mPendingLoader = null;
|
|
}
|
|
if (DEBUG) Log.v(TAG, " Enqueuing as new pending loader");
|
|
info.mPendingLoader = createLoader(id, args,
|
|
(LoaderManager.LoaderCallbacks<Object>)callback);
|
|
return (Loader<D>)info.mPendingLoader.mLoader;
|
|
}
|
|
}
|
|
} else {
|
|
// Keep track of the previous instance of this loader so we can destroy
|
|
// it when the new one completes.
|
|
if (DEBUG) Log.v(TAG, " Making last loader inactive: " + info);
|
|
info.mLoader.abandon();
|
|
mInactiveLoaders.put(id, info);
|
|
}
|
|
}
|
|
|
|
info = createAndInstallLoader(id, args, (LoaderManager.LoaderCallbacks<Object>)callback);
|
|
return (Loader<D>)info.mLoader;
|
|
}
|
|
|
|
/**
|
|
* Rip down, tear apart, shred to pieces a current Loader ID. After returning
|
|
* from this function, any Loader objects associated with this ID are
|
|
* destroyed. Any data associated with them is destroyed. You better not
|
|
* be using it when you do this.
|
|
* @param id Identifier of the Loader to be destroyed.
|
|
*/
|
|
public void destroyLoader(int id) {
|
|
if (mCreatingLoader) {
|
|
throw new IllegalStateException("Called while creating a loader");
|
|
}
|
|
|
|
if (DEBUG) Log.v(TAG, "destroyLoader in " + this + " of " + id);
|
|
int idx = mLoaders.indexOfKey(id);
|
|
if (idx >= 0) {
|
|
LoaderInfo info = mLoaders.valueAt(idx);
|
|
mLoaders.removeAt(idx);
|
|
info.destroy();
|
|
}
|
|
idx = mInactiveLoaders.indexOfKey(id);
|
|
if (idx >= 0) {
|
|
LoaderInfo info = mInactiveLoaders.valueAt(idx);
|
|
mInactiveLoaders.removeAt(idx);
|
|
info.destroy();
|
|
}
|
|
if (mHost != null && !hasRunningLoaders()) {
|
|
mHost.mFragmentManager.startPendingDeferredFragments();
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Return the most recent Loader object associated with the
|
|
* given ID.
|
|
*/
|
|
@SuppressWarnings("unchecked")
|
|
public <D> Loader<D> getLoader(int id) {
|
|
if (mCreatingLoader) {
|
|
throw new IllegalStateException("Called while creating a loader");
|
|
}
|
|
|
|
LoaderInfo loaderInfo = mLoaders.get(id);
|
|
if (loaderInfo != null) {
|
|
if (loaderInfo.mPendingLoader != null) {
|
|
return (Loader<D>)loaderInfo.mPendingLoader.mLoader;
|
|
}
|
|
return (Loader<D>)loaderInfo.mLoader;
|
|
}
|
|
return null;
|
|
}
|
|
|
|
void doStart() {
|
|
if (DEBUG) Log.v(TAG, "Starting in " + this);
|
|
if (mStarted) {
|
|
RuntimeException e = new RuntimeException("here");
|
|
e.fillInStackTrace();
|
|
Log.w(TAG, "Called doStart when already started: " + this, e);
|
|
return;
|
|
}
|
|
|
|
mStarted = true;
|
|
|
|
// Call out to sub classes so they can start their loaders
|
|
// Let the existing loaders know that we want to be notified when a load is complete
|
|
for (int i = mLoaders.size()-1; i >= 0; i--) {
|
|
mLoaders.valueAt(i).start();
|
|
}
|
|
}
|
|
|
|
void doStop() {
|
|
if (DEBUG) Log.v(TAG, "Stopping in " + this);
|
|
if (!mStarted) {
|
|
RuntimeException e = new RuntimeException("here");
|
|
e.fillInStackTrace();
|
|
Log.w(TAG, "Called doStop when not started: " + this, e);
|
|
return;
|
|
}
|
|
|
|
for (int i = mLoaders.size()-1; i >= 0; i--) {
|
|
mLoaders.valueAt(i).stop();
|
|
}
|
|
mStarted = false;
|
|
}
|
|
|
|
void doRetain() {
|
|
if (DEBUG) Log.v(TAG, "Retaining in " + this);
|
|
if (!mStarted) {
|
|
RuntimeException e = new RuntimeException("here");
|
|
e.fillInStackTrace();
|
|
Log.w(TAG, "Called doRetain when not started: " + this, e);
|
|
return;
|
|
}
|
|
|
|
mRetaining = true;
|
|
mStarted = false;
|
|
for (int i = mLoaders.size()-1; i >= 0; i--) {
|
|
mLoaders.valueAt(i).retain();
|
|
}
|
|
}
|
|
|
|
void finishRetain() {
|
|
if (mRetaining) {
|
|
if (DEBUG) Log.v(TAG, "Finished Retaining in " + this);
|
|
|
|
mRetaining = false;
|
|
for (int i = mLoaders.size()-1; i >= 0; i--) {
|
|
mLoaders.valueAt(i).finishRetain();
|
|
}
|
|
}
|
|
}
|
|
|
|
void doReportNextStart() {
|
|
for (int i = mLoaders.size()-1; i >= 0; i--) {
|
|
mLoaders.valueAt(i).mReportNextStart = true;
|
|
}
|
|
}
|
|
|
|
void doReportStart() {
|
|
for (int i = mLoaders.size()-1; i >= 0; i--) {
|
|
mLoaders.valueAt(i).reportStart();
|
|
}
|
|
}
|
|
|
|
void doDestroy() {
|
|
if (!mRetaining) {
|
|
if (DEBUG) Log.v(TAG, "Destroying Active in " + this);
|
|
for (int i = mLoaders.size()-1; i >= 0; i--) {
|
|
mLoaders.valueAt(i).destroy();
|
|
}
|
|
mLoaders.clear();
|
|
}
|
|
|
|
if (DEBUG) Log.v(TAG, "Destroying Inactive in " + this);
|
|
for (int i = mInactiveLoaders.size()-1; i >= 0; i--) {
|
|
mInactiveLoaders.valueAt(i).destroy();
|
|
}
|
|
mInactiveLoaders.clear();
|
|
mHost = null;
|
|
}
|
|
|
|
@Override
|
|
public String toString() {
|
|
StringBuilder sb = new StringBuilder(128);
|
|
sb.append("LoaderManager{");
|
|
sb.append(Integer.toHexString(System.identityHashCode(this)));
|
|
sb.append(" in ");
|
|
DebugUtils.buildShortClassTag(mHost, sb);
|
|
sb.append("}}");
|
|
return sb.toString();
|
|
}
|
|
|
|
@Override
|
|
public void dump(String prefix, FileDescriptor fd, PrintWriter writer, String[] args) {
|
|
if (mLoaders.size() > 0) {
|
|
writer.print(prefix); writer.println("Active Loaders:");
|
|
String innerPrefix = prefix + " ";
|
|
for (int i=0; i < mLoaders.size(); i++) {
|
|
LoaderInfo li = mLoaders.valueAt(i);
|
|
writer.print(prefix); writer.print(" #"); writer.print(mLoaders.keyAt(i));
|
|
writer.print(": "); writer.println(li.toString());
|
|
li.dump(innerPrefix, fd, writer, args);
|
|
}
|
|
}
|
|
if (mInactiveLoaders.size() > 0) {
|
|
writer.print(prefix); writer.println("Inactive Loaders:");
|
|
String innerPrefix = prefix + " ";
|
|
for (int i=0; i < mInactiveLoaders.size(); i++) {
|
|
LoaderInfo li = mInactiveLoaders.valueAt(i);
|
|
writer.print(prefix); writer.print(" #"); writer.print(mInactiveLoaders.keyAt(i));
|
|
writer.print(": "); writer.println(li.toString());
|
|
li.dump(innerPrefix, fd, writer, args);
|
|
}
|
|
}
|
|
}
|
|
|
|
public boolean hasRunningLoaders() {
|
|
boolean loadersRunning = false;
|
|
final int count = mLoaders.size();
|
|
for (int i = 0; i < count; i++) {
|
|
final LoaderInfo li = mLoaders.valueAt(i);
|
|
loadersRunning |= li.mStarted && !li.mDeliveredData;
|
|
}
|
|
return loadersRunning;
|
|
}
|
|
}
|