| /* |
| * Copyright (C) 2012 Google Inc. |
| * Licensed to The Android Open Source Project. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package com.android.mail.ui; |
| |
| import android.app.Activity; |
| import android.content.AsyncTaskLoader; |
| import android.net.Uri; |
| |
| import com.android.mail.browse.ConversationCursor; |
| import com.android.mail.providers.Account; |
| import com.android.mail.providers.UIProvider.AccountCapabilities; |
| import com.android.mail.utils.LogUtils; |
| |
| import java.util.ArrayList; |
| |
| public class ConversationCursorLoader extends AsyncTaskLoader<ConversationCursor> { |
| private static final String TAG = "ConversationCursorLoader"; |
| private final Uri mUri; |
| private final ConversationCursor mConversationCursor; |
| private boolean mInit = false; |
| private boolean mClosed = false; |
| private boolean mRetain = false; |
| private boolean mRetained = false; |
| private final String mName; |
| |
| /** Only used for debugging. Turn {@link #DEBUG} on to make this useful. */ |
| private static final boolean DEBUG = false; |
| private static final ArrayList<ConversationCursorLoader> sLoaders = |
| new ArrayList<ConversationCursorLoader>(); |
| |
| public ConversationCursorLoader(Activity activity, Account account, |
| Uri uri, String name, boolean ignoreInitialConversationLimit) { |
| super(activity); |
| mUri = uri; |
| mName = name; |
| final boolean useInitialConversationLimit = ignoreInitialConversationLimit ? false : |
| account.supportsCapability(AccountCapabilities.INITIAL_CONVERSATION_LIMIT); |
| // Initialize the state of the conversation cursor |
| mConversationCursor = new ConversationCursor( |
| activity, mUri, useInitialConversationLimit, name); |
| addLoader(); |
| } |
| |
| private static void dumpLoaders() { |
| if (DEBUG) { |
| LogUtils.d(TAG, "Loaders: "); |
| for (ConversationCursorLoader loader: sLoaders) { |
| LogUtils.d(TAG, " >> " + loader.mName + " (" + loader.mUri + ")"); |
| } |
| } |
| } |
| |
| private void addLoader() { |
| if (DEBUG) { |
| LogUtils.d(TAG, "Add loader: " + mUri); |
| sLoaders.add(this); |
| if (sLoaders.size() > 1) { |
| dumpLoaders(); |
| } |
| } |
| } |
| |
| /** |
| * Indicate whether the loader's cursor should be retained after reset |
| * @param state whether this laoder's cursor should be retained |
| */ |
| public void retainCursor(boolean state) { |
| mRetain = state; |
| } |
| |
| @Override |
| public void onReset() { |
| if (!mRetain) { |
| // Mark the cursor as disabled |
| mConversationCursor.disable(); |
| mClosed = true; |
| if (DEBUG) { |
| LogUtils.d(TAG, "Reset loader/disable cursor: " + mName); |
| sLoaders.remove(this); |
| if (!sLoaders.isEmpty()) { |
| dumpLoaders(); |
| } |
| } |
| } else { |
| if (DEBUG) { |
| LogUtils.d(TAG, "Reset loader/retain cursor: " + mName); |
| mRetained = true; |
| } |
| } |
| } |
| |
| @Override |
| public ConversationCursor loadInBackground() { |
| if (!mInit) { |
| mConversationCursor.load(); |
| mInit = true; |
| } |
| return mConversationCursor; |
| } |
| |
| @Override |
| protected void onStartLoading() { |
| if (mClosed) { |
| mClosed = false; |
| mConversationCursor.load(); |
| addLoader(); |
| if (DEBUG) { |
| LogUtils.d(TAG, "Restarting reset loader: " + mName); |
| } |
| } else if (mRetained) { |
| mRetained = false; |
| if (DEBUG) { |
| LogUtils.d(TAG, "Resuming retained loader: " + mName); |
| } |
| } |
| forceLoad(); |
| mConversationCursor.resume(); |
| } |
| |
| @Override |
| protected void onStopLoading() { |
| cancelLoad(); |
| mConversationCursor.pause(); |
| } |
| } |