Java tutorial
/* * Copyright (C) 2012 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.widget; import android.app.PendingIntent; import android.appwidget.AppWidgetManager; import android.content.Context; import android.content.CursorLoader; import android.content.Intent; import android.content.Loader; import android.content.Loader.OnLoadCompleteListener; import android.content.res.Resources; import android.database.Cursor; import android.net.Uri; import android.os.Looper; import android.support.v4.app.TaskStackBuilder; import android.text.SpannableString; import android.text.SpannableStringBuilder; import android.text.TextUtils; import android.text.format.DateUtils; import android.text.style.CharacterStyle; import android.view.View; import android.widget.RemoteViews; import android.widget.RemoteViewsService; import com.android.mail.R; import com.android.mail.browse.ConversationItemView; import com.android.mail.browse.SendersView; import com.android.mail.compose.ComposeActivity; import com.android.mail.preferences.MailPrefs; import com.android.mail.providers.Account; import com.android.mail.providers.Conversation; import com.android.mail.providers.Folder; import com.android.mail.providers.UIProvider; import com.android.mail.providers.UIProvider.ConversationListQueryParameters; import com.android.mail.providers.UIProvider.FolderType; import com.android.mail.utils.AccountUtils; import com.android.mail.utils.DelayedTaskHandler; import com.android.mail.utils.FolderUri; import com.android.mail.utils.LogTag; import com.android.mail.utils.LogUtils; import com.android.mail.utils.Utils; import java.util.ArrayList; import java.util.List; public class WidgetService extends RemoteViewsService { /** * Lock to avoid race condition between widgets. */ private static final Object sWidgetLock = new Object(); private static final String LOG_TAG = LogTag.getLogTag(); @Override public RemoteViewsFactory onGetViewFactory(Intent intent) { return new MailFactory(getApplicationContext(), intent, this); } protected void configureValidAccountWidget(Context context, RemoteViews remoteViews, int appWidgetId, Account account, final int folderType, final int folderCapabilities, final Uri folderUri, final Uri folderConversationListUri, String folderName) { configureValidAccountWidget(context, remoteViews, appWidgetId, account, folderType, folderCapabilities, folderUri, folderConversationListUri, folderName, WidgetService.class); } /** * Modifies the remoteView for the given account and folder. */ public static void configureValidAccountWidget(Context context, RemoteViews remoteViews, int appWidgetId, Account account, final int folderType, final int folderCapabilities, final Uri folderUri, final Uri folderConversationListUri, String folderDisplayName, Class<?> widgetService) { remoteViews.setViewVisibility(R.id.widget_folder, View.VISIBLE); // If the folder or account name are empty, we don't want to overwrite the valid data that // had been saved previously. Since the launcher will save the state of the remote views // we should rely on the fact that valid data has been saved. But we should still log this, // as it shouldn't happen if (TextUtils.isEmpty(folderDisplayName) || TextUtils.isEmpty(account.getDisplayName())) { LogUtils.e(LOG_TAG, new Error(), "Empty folder or account name. account: %s, folder: %s", account.getEmailAddress(), folderDisplayName); } if (!TextUtils.isEmpty(folderDisplayName)) { remoteViews.setTextViewText(R.id.widget_folder, folderDisplayName); } remoteViews.setViewVisibility(R.id.widget_compose, View.VISIBLE); remoteViews.setViewVisibility(R.id.conversation_list, View.VISIBLE); remoteViews.setViewVisibility(R.id.empty_conversation_list, View.VISIBLE); remoteViews.setViewVisibility(R.id.widget_folder_not_synced, View.GONE); remoteViews.setViewVisibility(R.id.widget_configuration, View.GONE); remoteViews.setEmptyView(R.id.conversation_list, R.id.empty_conversation_list); WidgetService.configureValidWidgetIntents(context, remoteViews, appWidgetId, account, folderType, folderCapabilities, folderUri, folderConversationListUri, folderDisplayName, widgetService); } public static void configureValidWidgetIntents(Context context, RemoteViews remoteViews, int appWidgetId, Account account, final int folderType, final int folderCapabilities, final Uri folderUri, final Uri folderConversationListUri, final String folderDisplayName, Class<?> serviceClass) { remoteViews.setViewVisibility(R.id.widget_configuration, View.GONE); // Launch an intent to avoid ANRs final Intent intent = new Intent(context, serviceClass); intent.putExtra(AppWidgetManager.EXTRA_APPWIDGET_ID, appWidgetId); intent.putExtra(Utils.EXTRA_ACCOUNT, account.serialize()); intent.putExtra(BaseWidgetProvider.EXTRA_FOLDER_TYPE, folderType); intent.putExtra(BaseWidgetProvider.EXTRA_FOLDER_CAPABILITIES, folderCapabilities); intent.putExtra(BaseWidgetProvider.EXTRA_FOLDER_URI, folderUri); intent.putExtra(BaseWidgetProvider.EXTRA_FOLDER_CONVERSATION_LIST_URI, folderConversationListUri); intent.putExtra(BaseWidgetProvider.EXTRA_FOLDER_DISPLAY_NAME, folderDisplayName); intent.setData(Uri.parse(intent.toUri(Intent.URI_INTENT_SCHEME))); remoteViews.setRemoteAdapter(R.id.conversation_list, intent); // Open mail app when click on header final Intent mailIntent = Utils.createViewFolderIntent(context, folderUri, account); mailIntent.setPackage(context.getPackageName()); PendingIntent clickIntent = PendingIntent.getActivity(context, 0, mailIntent, PendingIntent.FLAG_UPDATE_CURRENT); remoteViews.setOnClickPendingIntent(R.id.widget_header, clickIntent); // On click intent for Compose final Intent composeIntent = new Intent(); composeIntent.setPackage(context.getPackageName()); composeIntent.setAction(Intent.ACTION_SEND); composeIntent.putExtra(Utils.EXTRA_ACCOUNT, account.serialize()); composeIntent.setData(account.composeIntentUri); composeIntent.putExtra(ComposeActivity.EXTRA_FROM_EMAIL_TASK, true); if (account.composeIntentUri != null) { composeIntent.putExtra(Utils.EXTRA_COMPOSE_URI, account.composeIntentUri); } // Build a task stack that forces the conversation list on the stack before the compose // activity. final TaskStackBuilder taskStackBuilder = TaskStackBuilder.create(context); clickIntent = taskStackBuilder.addNextIntent(mailIntent).addNextIntent(composeIntent).getPendingIntent(0, PendingIntent.FLAG_UPDATE_CURRENT); remoteViews.setOnClickPendingIntent(R.id.widget_compose, clickIntent); // On click intent for Conversation final Intent conversationIntent = new Intent(); conversationIntent.setPackage(context.getPackageName()); conversationIntent.setAction(Intent.ACTION_VIEW); clickIntent = PendingIntent.getActivity(context, 0, conversationIntent, PendingIntent.FLAG_UPDATE_CURRENT); remoteViews.setPendingIntentTemplate(R.id.conversation_list, clickIntent); } /** * Persists the information about the specified widget. */ public static void saveWidgetInformation(Context context, int appWidgetId, Account account, final String folderUri) { MailPrefs.get(context).configureWidget(appWidgetId, account, folderUri); } /** * Returns true if this widget id has been configured and saved. */ public boolean isWidgetConfigured(Context context, int appWidgetId, Account account) { return isAccountValid(context, account) && MailPrefs.get(context).isWidgetConfigured(appWidgetId); } protected boolean isAccountValid(Context context, Account account) { if (account != null) { Account[] accounts = AccountUtils.getSyncingAccounts(context); for (Account existing : accounts) { if (existing != null && account.uri.equals(existing.uri)) { return true; } } } return false; } /** * Remote Views Factory for Mail Widget. */ protected static class MailFactory implements RemoteViewsService.RemoteViewsFactory, OnLoadCompleteListener<Cursor> { private static final int MAX_CONVERSATIONS_COUNT = 25; private static final int MAX_SENDERS_LENGTH = 25; private static final int FOLDER_LOADER_ID = 0; private static final int CONVERSATION_CURSOR_LOADER_ID = 1; private static final int ACCOUNT_LOADER_ID = 2; private final Context mContext; private final int mAppWidgetId; private final Account mAccount; private final int mFolderType; private final int mFolderCapabilities; private final Uri mFolderUri; private final Uri mFolderConversationListUri; private final String mFolderDisplayName; private final WidgetConversationListItemViewBuilder mWidgetConversationListItemViewBuilder; private CursorLoader mConversationCursorLoader; private Cursor mConversationCursor; private CursorLoader mFolderLoader; private CursorLoader mAccountLoader; private FolderUpdateHandler mFolderUpdateHandler; private int mFolderCount; private boolean mShouldShowViewMore; private boolean mFolderInformationShown = false; private final WidgetService mService; private String mSendersSplitToken; private String mElidedPaddingToken; public MailFactory(Context context, Intent intent, WidgetService service) { mContext = context; mAppWidgetId = intent.getIntExtra(AppWidgetManager.EXTRA_APPWIDGET_ID, AppWidgetManager.INVALID_APPWIDGET_ID); mAccount = Account.newInstance(intent.getStringExtra(Utils.EXTRA_ACCOUNT)); mFolderType = intent.getIntExtra(WidgetProvider.EXTRA_FOLDER_TYPE, FolderType.DEFAULT); mFolderCapabilities = intent.getIntExtra(WidgetProvider.EXTRA_FOLDER_CAPABILITIES, 0); mFolderDisplayName = intent.getStringExtra(WidgetProvider.EXTRA_FOLDER_DISPLAY_NAME); final Uri folderUri = intent.getParcelableExtra(WidgetProvider.EXTRA_FOLDER_URI); final Uri folderConversationListUri = intent .getParcelableExtra(WidgetProvider.EXTRA_FOLDER_CONVERSATION_LIST_URI); if (folderUri != null && folderConversationListUri != null) { mFolderUri = folderUri; mFolderConversationListUri = folderConversationListUri; } else { // This is a old intent created in version UR8 (or earlier). String folderString = intent.getStringExtra(Utils.EXTRA_FOLDER); //noinspection deprecation Folder folder = Folder.fromString(folderString); if (folder != null) { mFolderUri = folder.folderUri.fullUri; mFolderConversationListUri = folder.conversationListUri; } else { mFolderUri = Uri.EMPTY; mFolderConversationListUri = Uri.EMPTY; // this will mark the widget as unconfigured BaseWidgetProvider.updateWidget(mContext, mAppWidgetId, mAccount, mFolderType, mFolderCapabilities, mFolderUri, mFolderConversationListUri, mFolderDisplayName); } } mWidgetConversationListItemViewBuilder = new WidgetConversationListItemViewBuilder(context); mService = service; } @Override public void onCreate() { // Save the map between widgetId and account to preference saveWidgetInformation(mContext, mAppWidgetId, mAccount, mFolderUri.toString()); // If the account of this widget has been removed, we want to update the widget to // "Tap to configure" mode. if (!mService.isWidgetConfigured(mContext, mAppWidgetId, mAccount)) { BaseWidgetProvider.updateWidget(mContext, mAppWidgetId, mAccount, mFolderType, mFolderCapabilities, mFolderUri, mFolderConversationListUri, mFolderDisplayName); } mFolderInformationShown = false; // We want to limit the query result to 25 and don't want these queries to cause network // traffic // We also want this cursor to receive notifications on all changes. Any change that // the user made locally, the default policy of the UI provider is to not send // notifications for. But in this case, since the widget is not using the // ConversationCursor instance that the UI is using, the widget would not be updated. final Uri.Builder builder = mFolderConversationListUri.buildUpon(); final String maxConversations = Integer.toString(MAX_CONVERSATIONS_COUNT); final Uri widgetConversationQueryUri = builder .appendQueryParameter(ConversationListQueryParameters.LIMIT, maxConversations) .appendQueryParameter(ConversationListQueryParameters.USE_NETWORK, Boolean.FALSE.toString()) .appendQueryParameter(ConversationListQueryParameters.ALL_NOTIFICATIONS, Boolean.TRUE.toString()) .build(); final Resources res = mContext.getResources(); mConversationCursorLoader = new CursorLoader(mContext, widgetConversationQueryUri, UIProvider.CONVERSATION_PROJECTION, null, null, null); mConversationCursorLoader.registerListener(CONVERSATION_CURSOR_LOADER_ID, this); mConversationCursorLoader.setUpdateThrottle(res.getInteger(R.integer.widget_refresh_delay_ms)); mConversationCursorLoader.startLoading(); mSendersSplitToken = res.getString(R.string.senders_split_token); mElidedPaddingToken = res.getString(R.string.elided_padding_token); mFolderLoader = new CursorLoader(mContext, mFolderUri, UIProvider.FOLDERS_PROJECTION, null, null, null); mFolderLoader.registerListener(FOLDER_LOADER_ID, this); mFolderUpdateHandler = new FolderUpdateHandler( res.getInteger(R.integer.widget_folder_refresh_delay_ms)); mFolderUpdateHandler.scheduleTask(); mAccountLoader = new CursorLoader(mContext, mAccount.uri, UIProvider.ACCOUNTS_PROJECTION_NO_CAPABILITIES, null, null, null); mAccountLoader.registerListener(ACCOUNT_LOADER_ID, this); mAccountLoader.startLoading(); } @Override public void onDestroy() { synchronized (sWidgetLock) { if (mConversationCursorLoader != null) { mConversationCursorLoader.reset(); mConversationCursorLoader.unregisterListener(this); mConversationCursorLoader = null; } // The Loader should close the cursor, so just unset the reference // to it here. mConversationCursor = null; } if (mFolderLoader != null) { mFolderLoader.reset(); mFolderLoader.unregisterListener(this); mFolderLoader = null; } if (mAccountLoader != null) { mAccountLoader.reset(); mAccountLoader.unregisterListener(this); mAccountLoader = null; } } @Override public void onDataSetChanged() { // We are not using this as signal to requery the cursor. The query will be started // in the following ways: // 1) The Service is started and the loader is started in onCreate() // This will happen when the service is not running, and // AppWidgetManager#notifyAppWidgetViewDataChanged() is called // 2) The service is running, with a previously created loader. The loader is watching // for updates from the existing cursor. If one is seen, the loader will load a new // cursor in the background. mFolderUpdateHandler.scheduleTask(); } /** * Returns the number of items should be shown in the widget list. This method also updates * the boolean that indicates whether the "show more" item should be shown. * @return the number of items to be displayed in the list. */ @Override public int getCount() { synchronized (sWidgetLock) { final int count = getConversationCount(); final int cursorCount = mConversationCursor != null ? mConversationCursor.getCount() : 0; mShouldShowViewMore = count < cursorCount || count < mFolderCount; return count + (mShouldShowViewMore ? 1 : 0); } } /** * Returns the number of conversations that should be shown in the widget. This method * doesn't update the boolean that indicates that the "show more" item should be included * in the list. * @return count */ private int getConversationCount() { synchronized (sWidgetLock) { final int cursorCount = mConversationCursor != null ? mConversationCursor.getCount() : 0; return Math.min(cursorCount, MAX_CONVERSATIONS_COUNT); } } /** * @return the {@link RemoteViews} for a specific position in the list. */ @Override public RemoteViews getViewAt(int position) { synchronized (sWidgetLock) { // "View more conversations" view. if (mConversationCursor == null || mConversationCursor.isClosed() || (mShouldShowViewMore && position >= getConversationCount())) { return getViewMoreConversationsView(); } if (!mConversationCursor.moveToPosition(position)) { // If we ever fail to move to a position, return the // "View More conversations" // view. LogUtils.e(LOG_TAG, "Failed to move to position %d in the cursor.", position); return getViewMoreConversationsView(); } Conversation conversation = new Conversation(mConversationCursor); // Split the senders and status from the instructions. ArrayList<SpannableString> senders = new ArrayList<SpannableString>(); SendersView.format(mContext, conversation.conversationInfo, "", MAX_SENDERS_LENGTH, senders, null, null, mAccount, Folder.shouldShowRecipients(mFolderCapabilities), true); final SpannableStringBuilder senderBuilder = elideParticipants(senders); // Get styled date. CharSequence date = DateUtils.getRelativeTimeSpanString(mContext, conversation.dateMs); final int ignoreFolderType; if ((mFolderType & FolderType.INBOX) != 0) { ignoreFolderType = FolderType.INBOX; } else { ignoreFolderType = -1; } // Load up our remote view. RemoteViews remoteViews = mWidgetConversationListItemViewBuilder.getStyledView(mContext, date, conversation, new FolderUri(mFolderUri), ignoreFolderType, senderBuilder, ConversationItemView.filterTag(mContext, conversation.subject)); // On click intent. remoteViews.setOnClickFillInIntent(R.id.widget_conversation_list_item, Utils.createViewConversationIntent(mContext, conversation, mFolderUri, mAccount)); return remoteViews; } } private SpannableStringBuilder elideParticipants(List<SpannableString> parts) { final SpannableStringBuilder builder = new SpannableStringBuilder(); SpannableString prevSender = null; boolean skipToHeader = false; // start with "To: " if we're showing recipients if (Folder.shouldShowRecipients(mFolderCapabilities)) { builder.append(SendersView.getFormattedToHeader()); skipToHeader = true; } for (SpannableString sender : parts) { if (sender == null) { LogUtils.e(LOG_TAG, "null sender while iterating over styledSenders"); continue; } CharacterStyle[] spans = sender.getSpans(0, sender.length(), CharacterStyle.class); if (SendersView.sElidedString.equals(sender.toString())) { prevSender = sender; sender = copyStyles(spans, mElidedPaddingToken + sender + mElidedPaddingToken); } else if (!skipToHeader && builder.length() > 0 && (prevSender == null || !SendersView.sElidedString.equals(prevSender.toString()))) { prevSender = sender; sender = copyStyles(spans, mSendersSplitToken + sender); } else { prevSender = sender; skipToHeader = false; } builder.append(sender); } return builder; } private static SpannableString copyStyles(CharacterStyle[] spans, CharSequence newText) { SpannableString s = new SpannableString(newText); if (spans != null && spans.length > 0) { s.setSpan(spans[0], 0, s.length(), 0); } return s; } /** * @return the "View more conversations" view. */ private RemoteViews getViewMoreConversationsView() { RemoteViews view = new RemoteViews(mContext.getPackageName(), R.layout.widget_loading); view.setTextViewText(R.id.loading_text, mContext.getText(R.string.view_more_conversations)); view.setOnClickFillInIntent(R.id.widget_loading, Utils.createViewFolderIntent(mContext, mFolderUri, mAccount)); return view; } @Override public RemoteViews getLoadingView() { RemoteViews view = new RemoteViews(mContext.getPackageName(), R.layout.widget_loading); view.setTextViewText(R.id.loading_text, mContext.getText(R.string.loading_conversation)); return view; } @Override public int getViewTypeCount() { return 2; } @Override public long getItemId(int position) { return position; } @Override public boolean hasStableIds() { return false; } @Override public void onLoadComplete(Loader<Cursor> loader, Cursor data) { final AppWidgetManager appWidgetManager = AppWidgetManager.getInstance(mContext); final RemoteViews remoteViews = new RemoteViews(mContext.getPackageName(), R.layout.widget); if (!mService.isWidgetConfigured(mContext, mAppWidgetId, mAccount)) { BaseWidgetProvider.updateWidget(mContext, mAppWidgetId, mAccount, mFolderType, mFolderCapabilities, mFolderUri, mFolderConversationListUri, mFolderDisplayName); } if (loader == mFolderLoader) { if (!isDataValid(data)) { // Our folder may have disappeared on us BaseWidgetProvider.updateWidget(mContext, mAppWidgetId, mAccount, mFolderType, mFolderCapabilities, mFolderUri, mFolderConversationListUri, mFolderDisplayName); return; } final int unreadCount = data.getInt(UIProvider.FOLDER_UNREAD_COUNT_COLUMN); final String folderName = data.getString(UIProvider.FOLDER_NAME_COLUMN); mFolderCount = data.getInt(UIProvider.FOLDER_TOTAL_COUNT_COLUMN); if (!mFolderInformationShown && !TextUtils.isEmpty(folderName) && !TextUtils.isEmpty(mAccount.getDisplayName())) { // We want to do a full update to the widget at least once, as the widget // manager doesn't cache the state of the remote views when doing a partial // widget update. This causes the folder name to be shown as blank if the state // of the widget is restored. mService.configureValidAccountWidget(mContext, remoteViews, mAppWidgetId, mAccount, mFolderType, mFolderCapabilities, mFolderUri, mFolderConversationListUri, folderName); appWidgetManager.updateAppWidget(mAppWidgetId, remoteViews); mFolderInformationShown = true; } // There is no reason to overwrite a valid non-null folder name with an empty string if (!TextUtils.isEmpty(folderName)) { remoteViews.setViewVisibility(R.id.widget_folder, View.VISIBLE); remoteViews.setViewVisibility(R.id.widget_compose, View.VISIBLE); remoteViews.setTextViewText(R.id.widget_folder, folderName); } else { LogUtils.e(LOG_TAG, "Empty folder name"); } appWidgetManager.partiallyUpdateAppWidget(mAppWidgetId, remoteViews); } else if (loader == mConversationCursorLoader) { // We want to cache the new cursor synchronized (sWidgetLock) { if (!isDataValid(data)) { mConversationCursor = null; } else { mConversationCursor = data; } } appWidgetManager.notifyAppWidgetViewDataChanged(mAppWidgetId, R.id.conversation_list); if (mConversationCursor == null || mConversationCursor.getCount() == 0) { remoteViews.setTextViewText(R.id.empty_conversation_list, mContext.getString(R.string.empty_folder)); appWidgetManager.partiallyUpdateAppWidget(mAppWidgetId, remoteViews); } } else if (loader == mAccountLoader) { BaseWidgetProvider.updateWidget(mContext, mAppWidgetId, mAccount, mFolderType, mFolderCapabilities, mFolderUri, mFolderConversationListUri, mFolderDisplayName); } } /** * Returns a boolean indicating whether this cursor has valid data. * Note: This seeks to the first position in the cursor */ private static boolean isDataValid(Cursor cursor) { return cursor != null && !cursor.isClosed() && cursor.moveToFirst(); } /** * A {@link DelayedTaskHandler} to throttle folder update to a reasonable rate. */ private class FolderUpdateHandler extends DelayedTaskHandler { public FolderUpdateHandler(int refreshDelay) { super(Looper.myLooper(), refreshDelay); } @Override protected void performTask() { // Start the loader. The cached data will be returned if present. if (mFolderLoader != null) { mFolderLoader.startLoading(); } } } } }