WidgetService.java revision 8e99b95bf01c63f733fbd80c28c684350c7d702b
1/* 2 * Copyright (C) 2012 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16package com.android.mail.widget; 17 18import android.app.PendingIntent; 19import android.appwidget.AppWidgetManager; 20import android.content.Context; 21import android.content.CursorLoader; 22import android.content.Intent; 23import android.content.Loader; 24import android.content.Loader.OnLoadCompleteListener; 25import android.content.res.Resources; 26import android.database.Cursor; 27import android.net.Uri; 28import android.os.Looper; 29import android.support.v4.app.TaskStackBuilder; 30import android.text.SpannableString; 31import android.text.SpannableStringBuilder; 32import android.text.TextUtils; 33import android.text.format.DateUtils; 34import android.text.style.CharacterStyle; 35import android.text.style.TextAppearanceSpan; 36import android.view.View; 37import android.widget.RemoteViews; 38import android.widget.RemoteViewsService; 39 40import com.android.mail.R; 41import com.android.mail.browse.SendersView; 42import com.android.mail.compose.ComposeActivity; 43import com.android.mail.preferences.MailPrefs; 44import com.android.mail.providers.Account; 45import com.android.mail.providers.Conversation; 46import com.android.mail.providers.Folder; 47import com.android.mail.providers.UIProvider; 48import com.android.mail.providers.UIProvider.ConversationListQueryParameters; 49import com.android.mail.providers.UIProvider.FolderType; 50import com.android.mail.utils.AccountUtils; 51import com.android.mail.utils.DelayedTaskHandler; 52import com.android.mail.utils.LogTag; 53import com.android.mail.utils.LogUtils; 54import com.android.mail.utils.Utils; 55 56import java.util.ArrayList; 57 58public class WidgetService extends RemoteViewsService { 59 /** 60 * Lock to avoid race condition between widgets. 61 */ 62 private static Object sWidgetLock = new Object(); 63 64 private static final String LOG_TAG = LogTag.getLogTag(); 65 66 @Override 67 public RemoteViewsFactory onGetViewFactory(Intent intent) { 68 return new MailFactory(getApplicationContext(), intent, this); 69 } 70 71 protected void configureValidAccountWidget(Context context, RemoteViews remoteViews, 72 int appWidgetId, Account account, final int folderType, final Uri folderUri, 73 final Uri folderConversationListUri, String folderName) { 74 configureValidAccountWidget(context, remoteViews, appWidgetId, account, folderType, 75 folderUri, folderConversationListUri, folderName, WidgetService.class); 76 } 77 78 /** 79 * Modifies the remoteView for the given account and folder. 80 */ 81 public static void configureValidAccountWidget(Context context, RemoteViews remoteViews, 82 int appWidgetId, Account account, final int folderType, final Uri folderUri, 83 final Uri folderConversationListUri, String folderDisplayName, Class<?> widgetService) { 84 remoteViews.setViewVisibility(R.id.widget_folder, View.VISIBLE); 85 86 // If the folder or account name are empty, we don't want to overwrite the valid data that 87 // had been saved previously. Since the launcher will save the state of the remote views 88 // we should rely on the fact that valid data has been saved. But we should still log this, 89 // as it shouldn't happen 90 if (TextUtils.isEmpty(folderDisplayName) || TextUtils.isEmpty(account.name)) { 91 LogUtils.e(LOG_TAG, new Error(), 92 "Empty folder or account name. account: %s, folder: %s", 93 account.name, folderDisplayName); 94 } 95 if (!TextUtils.isEmpty(folderDisplayName)) { 96 remoteViews.setTextViewText(R.id.widget_folder, folderDisplayName); 97 } 98 remoteViews.setViewVisibility(R.id.widget_account, View.VISIBLE); 99 100 if (!TextUtils.isEmpty(account.name)) { 101 remoteViews.setTextViewText(R.id.widget_account, account.name); 102 } 103 remoteViews.setViewVisibility(R.id.widget_unread_count, View.VISIBLE); 104 remoteViews.setViewVisibility(R.id.widget_compose, View.VISIBLE); 105 remoteViews.setViewVisibility(R.id.conversation_list, View.VISIBLE); 106 remoteViews.setViewVisibility(R.id.widget_folder_not_synced, View.GONE); 107 remoteViews.setEmptyView(R.id.conversation_list, R.id.empty_conversation_list); 108 109 WidgetService.configureValidWidgetIntents(context, remoteViews, appWidgetId, account, 110 folderType, folderUri, folderConversationListUri, folderDisplayName, widgetService); 111 } 112 113 public static void configureValidWidgetIntents(Context context, RemoteViews remoteViews, 114 int appWidgetId, Account account, final int folderType, final Uri folderUri, 115 final Uri folderConversationListUri, final String folderDisplayName, 116 Class<?> serviceClass) { 117 remoteViews.setViewVisibility(R.id.widget_configuration, View.GONE); 118 119 120 // Launch an intent to avoid ANRs 121 final Intent intent = new Intent(context, serviceClass); 122 intent.putExtra(AppWidgetManager.EXTRA_APPWIDGET_ID, appWidgetId); 123 intent.putExtra(BaseWidgetProvider.EXTRA_ACCOUNT, account.serialize()); 124 intent.putExtra(BaseWidgetProvider.EXTRA_FOLDER_TYPE, folderType); 125 intent.putExtra(BaseWidgetProvider.EXTRA_FOLDER_URI, folderUri); 126 intent.putExtra(BaseWidgetProvider.EXTRA_FOLDER_CONVERSATION_LIST_URI, 127 folderConversationListUri); 128 intent.putExtra(BaseWidgetProvider.EXTRA_FOLDER_DISPLAY_NAME, folderDisplayName); 129 intent.setData(Uri.parse(intent.toUri(Intent.URI_INTENT_SCHEME))); 130 remoteViews.setRemoteAdapter(R.id.conversation_list, intent); 131 // Open mail app when click on header 132 final Intent mailIntent = Utils.createViewFolderIntent(context, folderUri, account); 133 PendingIntent clickIntent = PendingIntent.getActivity(context, 0, mailIntent, 134 PendingIntent.FLAG_UPDATE_CURRENT); 135 remoteViews.setOnClickPendingIntent(R.id.widget_header, clickIntent); 136 137 // On click intent for Compose 138 final Intent composeIntent = new Intent(); 139 composeIntent.setAction(Intent.ACTION_SEND); 140 composeIntent.putExtra(Utils.EXTRA_ACCOUNT, account.serialize()); 141 composeIntent.setData(account.composeIntentUri); 142 composeIntent.putExtra(ComposeActivity.EXTRA_FROM_EMAIL_TASK, true); 143 if (account.composeIntentUri != null) { 144 composeIntent.putExtra(Utils.EXTRA_COMPOSE_URI, account.composeIntentUri); 145 } 146 147 // Build a task stack that forces the conversation list on the stack before the compose 148 // activity. 149 final TaskStackBuilder taskStackBuilder = TaskStackBuilder.create(context); 150 clickIntent = taskStackBuilder.addNextIntent(mailIntent) 151 .addNextIntent(composeIntent) 152 .getPendingIntent(0, PendingIntent.FLAG_UPDATE_CURRENT); 153 remoteViews.setOnClickPendingIntent(R.id.widget_compose, clickIntent); 154 155 // On click intent for Conversation 156 final Intent conversationIntent = new Intent(); 157 conversationIntent.setAction(Intent.ACTION_VIEW); 158 clickIntent = PendingIntent.getActivity(context, 0, conversationIntent, 159 PendingIntent.FLAG_UPDATE_CURRENT); 160 remoteViews.setPendingIntentTemplate(R.id.conversation_list, clickIntent); 161 } 162 163 /** 164 * Persists the information about the specified widget. 165 */ 166 public static void saveWidgetInformation(Context context, int appWidgetId, Account account, 167 final String folderUri) { 168 MailPrefs.get(context).configureWidget(appWidgetId, account, folderUri); 169 } 170 171 /** 172 * Returns true if this widget id has been configured and saved. 173 */ 174 public boolean isWidgetConfigured(Context context, int appWidgetId, Account account) { 175 return isAccountValid(context, account) && 176 MailPrefs.get(context).isWidgetConfigured(appWidgetId); 177 } 178 179 protected boolean isAccountValid(Context context, Account account) { 180 if (account != null) { 181 Account[] accounts = AccountUtils.getSyncingAccounts(context); 182 for (Account existing : accounts) { 183 if (account != null && existing != null && account.uri.equals(existing.uri)) { 184 return true; 185 } 186 } 187 } 188 return false; 189 } 190 191 /** 192 * Remote Views Factory for Mail Widget. 193 */ 194 protected static class MailFactory 195 implements RemoteViewsService.RemoteViewsFactory, OnLoadCompleteListener<Cursor> { 196 private static final int MAX_CONVERSATIONS_COUNT = 25; 197 private static final int MAX_SENDERS_LENGTH = 25; 198 199 private static final int FOLDER_LOADER_ID = 0; 200 private static final int CONVERSATION_CURSOR_LOADER_ID = 1; 201 202 private final Context mContext; 203 private final int mAppWidgetId; 204 private final Account mAccount; 205 private final int mFolderType; 206 private final Uri mFolderUri; 207 private final Uri mFolderConversationListUri; 208 private final String mFolderDisplayName; 209 private final WidgetConversationViewBuilder mWidgetConversationViewBuilder; 210 private CursorLoader mConversationCursorLoader; 211 private Cursor mConversationCursor; 212 private CursorLoader mFolderLoader; 213 private FolderUpdateHandler mFolderUpdateHandler; 214 private int mFolderCount; 215 private boolean mShouldShowViewMore; 216 private boolean mFolderInformationShown = false; 217 private WidgetService mService; 218 private String mSendersSplitToken; 219 private String mElidedPaddingToken; 220 private TextAppearanceSpan mUnreadStyle; 221 private TextAppearanceSpan mReadStyle; 222 223 public MailFactory(Context context, Intent intent, WidgetService service) { 224 mContext = context; 225 mAppWidgetId = intent.getIntExtra( 226 AppWidgetManager.EXTRA_APPWIDGET_ID, AppWidgetManager.INVALID_APPWIDGET_ID); 227 mAccount = Account.newinstance(intent.getStringExtra(WidgetProvider.EXTRA_ACCOUNT)); 228 mFolderType = intent.getIntExtra(WidgetProvider.EXTRA_FOLDER_TYPE, FolderType.DEFAULT); 229 mFolderDisplayName = intent.getStringExtra(WidgetProvider.EXTRA_FOLDER_DISPLAY_NAME); 230 231 Uri folderUri = intent.getParcelableExtra(WidgetProvider.EXTRA_FOLDER_URI); 232 Uri folderConversationListUri = 233 intent.getParcelableExtra(WidgetProvider.EXTRA_FOLDER_CONVERSATION_LIST_URI); 234 if (folderUri != null && folderConversationListUri != null) { 235 mFolderUri = folderUri; 236 mFolderConversationListUri = folderConversationListUri; 237 } else { 238 // This is a old intent created in version UR8 (or earlier). 239 String folderString = intent.getStringExtra("folder"); 240 Folder folder = Folder.fromString(folderString); 241 mFolderUri = folder.uri; 242 mFolderConversationListUri = folder.conversationListUri; 243 } 244 245 mWidgetConversationViewBuilder = new WidgetConversationViewBuilder(context); 246 mService = service; 247 } 248 249 @Override 250 public void onCreate() { 251 // Save the map between widgetId and account to preference 252 saveWidgetInformation(mContext, mAppWidgetId, mAccount, mFolderUri.toString()); 253 254 // If the account of this widget has been removed, we want to update the widget to 255 // "Tap to configure" mode. 256 if (!mService.isWidgetConfigured(mContext, mAppWidgetId, mAccount)) { 257 BaseWidgetProvider.updateWidget(mContext, mAppWidgetId, mAccount, mFolderType, 258 mFolderUri, mFolderConversationListUri, mFolderDisplayName); 259 } 260 261 mFolderInformationShown = false; 262 263 // We want to limit the query result to 25 and don't want these queries to cause network 264 // traffic 265 // We also want this cursor to receive notifications on all changes. Any change that 266 // the user made locally, the default policy of the UI provider is to not send 267 // notifications for. But in this case, since the widget is not using the 268 // ConversationCursor instance that the UI is using, the widget would not be updated. 269 final Uri.Builder builder = mFolderConversationListUri.buildUpon(); 270 final String maxConversations = Integer.toString(MAX_CONVERSATIONS_COUNT); 271 final Uri widgetConversationQueryUri = builder 272 .appendQueryParameter(ConversationListQueryParameters.LIMIT, maxConversations) 273 .appendQueryParameter(ConversationListQueryParameters.USE_NETWORK, 274 Boolean.FALSE.toString()) 275 .appendQueryParameter(ConversationListQueryParameters.ALL_NOTIFICATIONS, 276 Boolean.TRUE.toString()).build(); 277 278 final Resources res = mContext.getResources(); 279 mConversationCursorLoader = new CursorLoader(mContext, widgetConversationQueryUri, 280 UIProvider.CONVERSATION_PROJECTION, null, null, null); 281 mConversationCursorLoader.registerListener(CONVERSATION_CURSOR_LOADER_ID, this); 282 mConversationCursorLoader.setUpdateThrottle( 283 res.getInteger(R.integer.widget_refresh_delay_ms)); 284 mConversationCursorLoader.startLoading(); 285 mSendersSplitToken = res.getString(R.string.senders_split_token); 286 mElidedPaddingToken = res.getString(R.string.elided_padding_token); 287 mFolderLoader = new CursorLoader(mContext, mFolderUri, UIProvider.FOLDERS_PROJECTION, 288 null, null, null); 289 mFolderLoader.registerListener(FOLDER_LOADER_ID, this); 290 mFolderUpdateHandler = new FolderUpdateHandler( 291 res.getInteger(R.integer.widget_folder_refresh_delay_ms)); 292 mFolderUpdateHandler.scheduleTask(); 293 294 } 295 296 @Override 297 public void onDestroy() { 298 synchronized (sWidgetLock) { 299 if (mConversationCursorLoader != null) { 300 mConversationCursorLoader.reset(); 301 mConversationCursorLoader.unregisterListener(this); 302 mConversationCursorLoader = null; 303 } 304 305 // The Loader should close the cursor, so just unset the reference 306 // to it here. 307 mConversationCursor = null; 308 } 309 310 if (mFolderLoader != null) { 311 mFolderLoader.reset(); 312 mFolderLoader.unregisterListener(this); 313 mFolderLoader = null; 314 } 315 } 316 317 @Override 318 public void onDataSetChanged() { 319 // We are not using this as signal to requery the cursor. The query will be started 320 // in the following ways: 321 // 1) The Service is started and the loader is started in onCreate() 322 // This will happen when the service is not running, and 323 // AppWidgetManager#notifyAppWidgetViewDataChanged() is called 324 // 2) The service is running, with a previously created loader. The loader is watching 325 // for updates from the existing cursor. If one is seen, the loader will load a new 326 // cursor in the background. 327 mFolderUpdateHandler.scheduleTask(); 328 } 329 330 /** 331 * Returns the number of items should be shown in the widget list. This method also updates 332 * the boolean that indicates whether the "show more" item should be shown. 333 * @return the number of items to be displayed in the list. 334 */ 335 @Override 336 public int getCount() { 337 synchronized (sWidgetLock) { 338 final int count = getConversationCount(); 339 final int cursorCount = mConversationCursor != null ? 340 mConversationCursor.getCount() : 0; 341 mShouldShowViewMore = count < cursorCount || count < mFolderCount; 342 return count + (mShouldShowViewMore ? 1 : 0); 343 } 344 } 345 346 /** 347 * Returns the number of conversations that should be shown in the widget. This method 348 * doesn't update the boolean that indicates that the "show more" item should be included 349 * in the list. 350 * @return 351 */ 352 private int getConversationCount() { 353 synchronized (sWidgetLock) { 354 final int cursorCount = mConversationCursor != null ? 355 mConversationCursor.getCount() : 0; 356 return Math.min(cursorCount, MAX_CONVERSATIONS_COUNT); 357 } 358 } 359 360 /** 361 * @return the {@link RemoteViews} for a specific position in the list. 362 */ 363 @Override 364 public RemoteViews getViewAt(int position) { 365 synchronized (sWidgetLock) { 366 // "View more conversations" view. 367 if (mConversationCursor == null || mConversationCursor.isClosed() 368 || (mShouldShowViewMore && position >= getConversationCount())) { 369 return getViewMoreConversationsView(); 370 } 371 372 if (!mConversationCursor.moveToPosition(position)) { 373 // If we ever fail to move to a position, return the 374 // "View More conversations" 375 // view. 376 LogUtils.e(LOG_TAG, "Failed to move to position %d in the cursor.", position); 377 return getViewMoreConversationsView(); 378 } 379 380 Conversation conversation = new Conversation(mConversationCursor); 381 // Split the senders and status from the instructions. 382 SpannableStringBuilder senderBuilder = new SpannableStringBuilder(); 383 384 if (conversation.conversationInfo != null) { 385 ArrayList<SpannableString> senders = new ArrayList<SpannableString>(); 386 SendersView.format(mContext, conversation.conversationInfo, "", 387 MAX_SENDERS_LENGTH, senders, null, null, mAccount.name, true); 388 senderBuilder = ellipsizeStyledSenders(senders); 389 } else { 390 senderBuilder.append(conversation.senders); 391 senderBuilder.setSpan(conversation.read ? getReadStyle() : getUnreadStyle(), 0, 392 senderBuilder.length(), 0); 393 } 394 // Get styled date. 395 CharSequence date = DateUtils.getRelativeTimeSpanString(mContext, 396 conversation.dateMs); 397 398 final int ignoreFolderType; 399 if ((mFolderType & FolderType.INBOX) != 0) { 400 ignoreFolderType = FolderType.INBOX; 401 } else { 402 ignoreFolderType = -1; 403 } 404 405 // Load up our remote view. 406 RemoteViews remoteViews = mWidgetConversationViewBuilder.getStyledView(date, 407 conversation, mFolderUri, ignoreFolderType, senderBuilder, 408 filterTag(conversation.subject)); 409 410 // On click intent. 411 remoteViews.setOnClickFillInIntent(R.id.widget_conversation, 412 Utils.createViewConversationIntent(mContext, conversation, mFolderUri, 413 mAccount)); 414 415 return remoteViews; 416 } 417 } 418 419 private CharacterStyle getUnreadStyle() { 420 if (mUnreadStyle == null) { 421 mUnreadStyle = new TextAppearanceSpan(mContext, 422 R.style.SendersUnreadTextAppearance); 423 } 424 return CharacterStyle.wrap(mUnreadStyle); 425 } 426 427 private CharacterStyle getReadStyle() { 428 if (mReadStyle == null) { 429 mReadStyle = new TextAppearanceSpan(mContext, R.style.SendersReadTextAppearance); 430 } 431 return CharacterStyle.wrap(mReadStyle); 432 } 433 434 private SpannableStringBuilder ellipsizeStyledSenders( 435 ArrayList<SpannableString> styledSenders) { 436 SpannableStringBuilder builder = new SpannableStringBuilder(); 437 SpannableString prevSender = null; 438 for (SpannableString sender : styledSenders) { 439 if (sender == null) { 440 LogUtils.e(LOG_TAG, "null sender while iterating over styledSenders"); 441 continue; 442 } 443 CharacterStyle[] spans = sender.getSpans(0, sender.length(), CharacterStyle.class); 444 if (SendersView.sElidedString.equals(sender.toString())) { 445 prevSender = sender; 446 sender = copyStyles(spans, mElidedPaddingToken + sender + mElidedPaddingToken); 447 } else if (builder.length() > 0 448 && (prevSender == null || !SendersView.sElidedString.equals(prevSender 449 .toString()))) { 450 prevSender = sender; 451 sender = copyStyles(spans, mSendersSplitToken + sender); 452 } else { 453 prevSender = sender; 454 } 455 builder.append(sender); 456 } 457 return builder; 458 } 459 460 private static SpannableString copyStyles(CharacterStyle[] spans, CharSequence newText) { 461 SpannableString s = new SpannableString(newText); 462 if (spans != null && spans.length > 0) { 463 s.setSpan(spans[0], 0, s.length(), 0); 464 } 465 return s; 466 } 467 468 /** 469 * @return the "View more conversations" view. 470 */ 471 private RemoteViews getViewMoreConversationsView() { 472 RemoteViews view = new RemoteViews(mContext.getPackageName(), R.layout.widget_loading); 473 view.setTextViewText( 474 R.id.loading_text, mContext.getText(R.string.view_more_conversations)); 475 view.setOnClickFillInIntent(R.id.widget_loading, 476 Utils.createViewFolderIntent(mContext, mFolderUri, mAccount)); 477 return view; 478 } 479 480 @Override 481 public RemoteViews getLoadingView() { 482 RemoteViews view = new RemoteViews(mContext.getPackageName(), R.layout.widget_loading); 483 view.setTextViewText( 484 R.id.loading_text, mContext.getText(R.string.loading_conversation)); 485 return view; 486 } 487 488 @Override 489 public int getViewTypeCount() { 490 return 2; 491 } 492 493 @Override 494 public long getItemId(int position) { 495 return position; 496 } 497 498 @Override 499 public boolean hasStableIds() { 500 return false; 501 } 502 503 @Override 504 public void onLoadComplete(Loader<Cursor> loader, Cursor data) { 505 final AppWidgetManager appWidgetManager = AppWidgetManager.getInstance(mContext); 506 final RemoteViews remoteViews = 507 new RemoteViews(mContext.getPackageName(), R.layout.widget); 508 509 if (loader == mFolderLoader) { 510 if (!isDataValid(data)) { 511 return; 512 } 513 514 final int unreadCount = data.getInt(UIProvider.FOLDER_UNREAD_COUNT_COLUMN); 515 final String folderName = data.getString(UIProvider.FOLDER_NAME_COLUMN); 516 mFolderCount = data.getInt(UIProvider.FOLDER_TOTAL_COUNT_COLUMN); 517 518 if (!mFolderInformationShown && !TextUtils.isEmpty(folderName) && 519 !TextUtils.isEmpty(mAccount.name)) { 520 // We want to do a full update to the widget at least once, as the widget 521 // manager doesn't cache the state of the remote views when doing a partial 522 // widget update. This causes the folder name to be shown as blank if the state 523 // of the widget is restored. 524 mService.configureValidAccountWidget(mContext, remoteViews, mAppWidgetId, 525 mAccount, mFolderType, mFolderUri, mFolderConversationListUri, 526 folderName); 527 appWidgetManager.updateAppWidget(mAppWidgetId, remoteViews); 528 mFolderInformationShown = true; 529 } 530 531 // There is no reason to overwrite a valid non-null folder name with an empty string 532 if (!TextUtils.isEmpty(folderName)) { 533 remoteViews.setViewVisibility(R.id.widget_folder, View.VISIBLE); 534 remoteViews.setTextViewText(R.id.widget_folder, folderName); 535 } else { 536 LogUtils.e(LOG_TAG, "Empty folder name"); 537 } 538 if (!TextUtils.isEmpty(mAccount.name)) { 539 remoteViews.setTextViewText(R.id.widget_account, mAccount.name); 540 } 541 remoteViews.setViewVisibility(R.id.widget_unread_count, View.VISIBLE); 542 remoteViews.setTextViewText(R.id.widget_unread_count, 543 Utils.getUnreadCountString(mContext, unreadCount)); 544 545 appWidgetManager.partiallyUpdateAppWidget(mAppWidgetId, remoteViews); 546 } else if (loader == mConversationCursorLoader) { 547 // We want to cache the new cursor 548 synchronized (sWidgetLock) { 549 if (!isDataValid(data)) { 550 mConversationCursor = null; 551 } else { 552 mConversationCursor = data; 553 } 554 } 555 556 appWidgetManager.notifyAppWidgetViewDataChanged(mAppWidgetId, 557 R.id.conversation_list); 558 559 if (mConversationCursor == null || mConversationCursor.getCount() == 0) { 560 remoteViews.setTextViewText(R.id.empty_conversation_list, 561 mContext.getString(R.string.no_conversations)); 562 appWidgetManager.partiallyUpdateAppWidget(mAppWidgetId, remoteViews); 563 } 564 } 565 } 566 567 /** 568 * Returns a boolean indicating whether this cursor has valid data. 569 * Note: This seeks to the first position in the cursor 570 */ 571 private static boolean isDataValid(Cursor cursor) { 572 return cursor != null && !cursor.isClosed() && cursor.moveToFirst(); 573 } 574 575 /** 576 * If the subject contains the tag of a mailing-list (text surrounded with []), return the 577 * subject with that tag ellipsized, e.g. "[android-gmail-team] Hello" -> "[andr...] Hello" 578 */ 579 private static String filterTag(String subject) { 580 String result = subject; 581 if (subject.length() > 0 && subject.charAt(0) == '[') { 582 int end = subject.indexOf(']'); 583 if (end > 0) { 584 String tag = subject.substring(1, end); 585 result = "[" + Utils.ellipsize(tag, 7) + "]" + subject.substring(end + 1); 586 } 587 } 588 589 return result; 590 } 591 592 /** 593 * A {@link DelayedTaskHandler} to throttle folder update to a reasonable rate. 594 */ 595 private class FolderUpdateHandler extends DelayedTaskHandler { 596 public FolderUpdateHandler(int refreshDelay) { 597 super(Looper.myLooper(), refreshDelay); 598 } 599 600 @Override 601 protected void performTask() { 602 // Start the loader. The cached data will be returned if present. 603 if (mFolderLoader != null) { 604 mFolderLoader.startLoading(); 605 } 606 } 607 } 608 } 609} 610