The Tor Browser / file comparison
comparison: mobile/android/base/home/SimpleCursorLoader.java
mobile/android/base/home/SimpleCursorLoader.java
- branch
- TOR_BUG_3246
- changeset 4
- fc2d59ddac77
equal
deleted
inserted
replaced
| -1:000000000000 | 0:d1ee5fc0b6e4 |
|---|---|
| 1 /* | |
| 2 * This is an adapted version of Android's original CursorLoader | |
| 3 * without all the ContentProvider-specific bits. | |
| 4 * | |
| 5 * Copyright (C) 2011 The Android Open Source Project | |
| 6 * | |
| 7 * Licensed under the Apache License, Version 2.0 (the "License"); | |
| 8 * you may not use this file except in compliance with the License. | |
| 9 * You may obtain a copy of the License at | |
| 10 * | |
| 11 * http://www.apache.org/licenses/LICENSE-2.0 | |
| 12 * | |
| 13 * Unless required by applicable law or agreed to in writing, software | |
| 14 * distributed under the License is distributed on an "AS IS" BASIS, | |
| 15 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | |
| 16 * See the License for the specific language governing permissions and | |
| 17 * limitations under the License. | |
| 18 */ | |
| 19 | |
| 20 package org.mozilla.gecko.home; | |
| 21 | |
| 22 import android.content.Context; | |
| 23 import android.database.Cursor; | |
| 24 import android.support.v4.content.AsyncTaskLoader; | |
| 25 | |
| 26 abstract class SimpleCursorLoader extends AsyncTaskLoader<Cursor> { | |
| 27 final ForceLoadContentObserver mObserver; | |
| 28 Cursor mCursor; | |
| 29 | |
| 30 public SimpleCursorLoader(Context context) { | |
| 31 super(context); | |
| 32 mObserver = new ForceLoadContentObserver(); | |
| 33 } | |
| 34 | |
| 35 /** | |
| 36 * Loads the target cursor for this loader. This method is called | |
| 37 * on a worker thread. | |
| 38 */ | |
| 39 protected abstract Cursor loadCursor(); | |
| 40 | |
| 41 /* Runs on a worker thread */ | |
| 42 @Override | |
| 43 public Cursor loadInBackground() { | |
| 44 Cursor cursor = loadCursor(); | |
| 45 | |
| 46 if (cursor != null) { | |
| 47 // Ensure the cursor window is filled | |
| 48 cursor.getCount(); | |
| 49 cursor.registerContentObserver(mObserver); | |
| 50 } | |
| 51 | |
| 52 return cursor; | |
| 53 } | |
| 54 | |
| 55 /* Runs on the UI thread */ | |
| 56 @Override | |
| 57 public void deliverResult(Cursor cursor) { | |
| 58 if (isReset()) { | |
| 59 // An async query came in while the loader is stopped | |
| 60 if (cursor != null) { | |
| 61 cursor.close(); | |
| 62 } | |
| 63 | |
| 64 return; | |
| 65 } | |
| 66 | |
| 67 Cursor oldCursor = mCursor; | |
| 68 mCursor = cursor; | |
| 69 | |
| 70 if (isStarted()) { | |
| 71 super.deliverResult(cursor); | |
| 72 } | |
| 73 | |
| 74 if (oldCursor != null && oldCursor != cursor && !oldCursor.isClosed()) { | |
| 75 oldCursor.close(); | |
| 76 } | |
| 77 } | |
| 78 | |
| 79 /** | |
| 80 * Starts an asynchronous load of the list data. When the result is ready the callbacks | |
| 81 * will be called on the UI thread. If a previous load has been completed and is still valid | |
| 82 * the result may be passed to the callbacks immediately. | |
| 83 * | |
| 84 * Must be called from the UI thread | |
| 85 */ | |
| 86 @Override | |
| 87 protected void onStartLoading() { | |
| 88 if (mCursor != null) { | |
| 89 deliverResult(mCursor); | |
| 90 } | |
| 91 | |
| 92 if (takeContentChanged() || mCursor == null) { | |
| 93 forceLoad(); | |
| 94 } | |
| 95 } | |
| 96 | |
| 97 /** | |
| 98 * Must be called from the UI thread | |
| 99 */ | |
| 100 @Override | |
| 101 protected void onStopLoading() { | |
| 102 // Attempt to cancel the current load task if possible. | |
| 103 cancelLoad(); | |
| 104 } | |
| 105 | |
| 106 @Override | |
| 107 public void onCanceled(Cursor cursor) { | |
| 108 if (cursor != null && !cursor.isClosed()) { | |
| 109 cursor.close(); | |
| 110 } | |
| 111 } | |
| 112 | |
| 113 @Override | |
| 114 protected void onReset() { | |
| 115 super.onReset(); | |
| 116 | |
| 117 // Ensure the loader is stopped | |
| 118 onStopLoading(); | |
| 119 | |
| 120 if (mCursor != null && !mCursor.isClosed()) { | |
| 121 mCursor.close(); | |
| 122 } | |
| 123 | |
| 124 mCursor = null; | |
| 125 } | |
| 126 } |
