Java tutorial
/* * 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.SearchManager; import android.app.SearchableInfo; import android.content.ContentResolver; import android.content.Context; import android.database.Cursor; import android.net.Uri; import android.os.AsyncTask; import android.os.Bundle; import android.support.v4.view.MenuItemCompat; import android.support.v7.app.ActionBar; import android.support.v7.widget.SearchView; import android.support.v7.widget.SearchView.OnQueryTextListener; import android.support.v7.widget.SearchView.OnSuggestionListener; import android.text.TextUtils; import android.view.Menu; import android.view.MenuItem; import com.android.mail.ConversationListContext; import com.android.email.R; import com.android.mail.providers.Account; import com.android.mail.providers.AccountObserver; import com.android.mail.providers.Conversation; import com.android.mail.providers.Folder; import com.android.mail.providers.FolderObserver; import com.android.mail.providers.SearchRecentSuggestionsProvider; import com.android.mail.providers.UIProvider; import com.android.mail.providers.UIProvider.AccountCapabilities; import com.android.mail.providers.UIProvider.FolderCapabilities; import com.android.mail.providers.UIProvider.FolderType; import com.android.mail.utils.LogTag; import com.android.mail.utils.LogUtils; import com.android.mail.utils.Utils; /** * Controller to manage the various states of the {@link android.app.ActionBar}. */ public class ActionBarController implements ViewMode.ModeChangeListener, OnQueryTextListener, OnSuggestionListener, MenuItemCompat.OnActionExpandListener { private final Context mContext; protected ActionBar mActionBar; protected ControllableActivity mActivity; protected ActivityController mController; /** * The current mode of the ActionBar and Activity */ private ViewMode mViewModeController; /** * The account currently being shown */ private Account mAccount; /** * The folder currently being shown */ private Folder mFolder; private SearchView mSearchWidget; private MenuItem mSearch; private MenuItem mEmptyTrashItem; private MenuItem mEmptySpamItem; /** True if the current device is a tablet, false otherwise. */ protected final boolean mIsOnTablet; private Conversation mCurrentConversation; public static final String LOG_TAG = LogTag.getLogTag(); private FolderObserver mFolderObserver; /** Updates the resolver and tells it the most recent account. */ private final class UpdateProvider extends AsyncTask<Bundle, Void, Void> { final Uri mAccount; final ContentResolver mResolver; public UpdateProvider(Uri account, ContentResolver resolver) { mAccount = account; mResolver = resolver; } @Override protected Void doInBackground(Bundle... params) { mResolver.call(mAccount, UIProvider.AccountCallMethods.SET_CURRENT_ACCOUNT, mAccount.toString(), params[0]); return null; } } private final AccountObserver mAccountObserver = new AccountObserver() { @Override public void onChanged(Account newAccount) { updateAccount(newAccount); } }; public ActionBarController(Context context) { mContext = context; mIsOnTablet = Utils.useTabletUI(context.getResources()); } public void expandSearch() { if (mSearch != null) { MenuItemCompat.expandActionView(mSearch); } } /** * Close the search view if it is expanded. */ public void collapseSearch() { if (mSearch != null) { MenuItemCompat.collapseActionView(mSearch); } } /** * Get the search menu item. */ protected MenuItem getSearch() { return mSearch; } public boolean onCreateOptionsMenu(Menu menu) { mEmptyTrashItem = menu.findItem(R.id.empty_trash); mEmptySpamItem = menu.findItem(R.id.empty_spam); mSearch = menu.findItem(R.id.search); if (mSearch != null) { mSearchWidget = (SearchView) MenuItemCompat.getActionView(mSearch); MenuItemCompat.setOnActionExpandListener(mSearch, this); SearchManager searchManager = (SearchManager) mActivity.getActivityContext() .getSystemService(Context.SEARCH_SERVICE); if (searchManager != null && mSearchWidget != null) { SearchableInfo info = searchManager.getSearchableInfo(mActivity.getComponentName()); mSearchWidget.setSearchableInfo(info); mSearchWidget.setOnQueryTextListener(this); mSearchWidget.setOnSuggestionListener(this); mSearchWidget.setIconifiedByDefault(true); } } // the menu should be displayed if the mode is known return getMode() != ViewMode.UNKNOWN; } public int getOptionsMenuId() { switch (getMode()) { case ViewMode.UNKNOWN: return R.menu.conversation_list_menu; case ViewMode.CONVERSATION: return R.menu.conversation_actions; case ViewMode.CONVERSATION_LIST: return R.menu.conversation_list_menu; case ViewMode.SEARCH_RESULTS_LIST: return R.menu.conversation_list_search_results_actions; case ViewMode.SEARCH_RESULTS_CONVERSATION: return R.menu.conversation_actions; case ViewMode.WAITING_FOR_ACCOUNT_INITIALIZATION: return R.menu.wait_mode_actions; } LogUtils.wtf(LOG_TAG, "Menu requested for unknown view mode"); return R.menu.conversation_list_menu; } public void initialize(ControllableActivity activity, ActivityController callback, ActionBar actionBar) { mActionBar = actionBar; mController = callback; mActivity = activity; mFolderObserver = new FolderObserver() { @Override public void onChanged(Folder newFolder) { onFolderUpdated(newFolder); } }; // Return values are purposely discarded. Initialization happens quite early, and we don't // have a valid folder, or a valid list of accounts. mFolderObserver.initialize(mController); updateAccount(mAccountObserver.initialize(activity.getAccountController())); } private void updateAccount(Account account) { final boolean accountChanged = mAccount == null || !mAccount.uri.equals(account.uri); mAccount = account; if (mAccount != null && accountChanged) { final ContentResolver resolver = mActivity.getActivityContext().getContentResolver(); final Bundle bundle = new Bundle(1); bundle.putParcelable(UIProvider.SetCurrentAccountColumns.ACCOUNT, account); final UpdateProvider updater = new UpdateProvider(mAccount.uri, resolver); updater.execute(bundle); setFolderAndAccount(); } } /** * Called by the owner of the ActionBar to change the current folder. */ public void setFolder(Folder folder) { mFolder = folder; setFolderAndAccount(); } public void onDestroy() { if (mFolderObserver != null) { mFolderObserver.unregisterAndDestroy(); mFolderObserver = null; } mAccountObserver.unregisterAndDestroy(); } @Override public void onViewModeChanged(int newMode) { mActivity.supportInvalidateOptionsMenu(); // Check if we are either on a phone, or in Conversation mode on tablet. For these, the // recent folders is enabled. switch (getMode()) { case ViewMode.UNKNOWN: break; case ViewMode.CONVERSATION_LIST: showNavList(); break; case ViewMode.SEARCH_RESULTS_CONVERSATION: mActionBar.setDisplayHomeAsUpEnabled(true); setEmptyMode(); break; case ViewMode.CONVERSATION: case ViewMode.AD: closeSearchField(); mActionBar.setDisplayHomeAsUpEnabled(true); setEmptyMode(); break; case ViewMode.WAITING_FOR_ACCOUNT_INITIALIZATION: // We want the user to be able to switch accounts while waiting for an account // to sync. showNavList(); break; } } /** * Close the search query entry field to avoid keyboard events, and to restore the actionbar * to non-search mode. */ private void closeSearchField() { if (mSearch == null) { return; } mSearch.collapseActionView(); } protected int getMode() { if (mViewModeController != null) { return mViewModeController.getMode(); } else { return ViewMode.UNKNOWN; } } /** * Helper function to ensure that the menu items that are prone to variable changes and race * conditions are properly set to the correct visibility */ public void validateVolatileMenuOptionVisibility() { if (mEmptyTrashItem != null) { mEmptyTrashItem.setVisible(mAccount != null && mFolder != null && mAccount.supportsCapability(AccountCapabilities.EMPTY_TRASH) && mFolder.isTrash() && mFolder.totalCount > 0 && (mController.getConversationListCursor() == null || mController.getConversationListCursor().getCount() > 0)); } if (mEmptySpamItem != null) { mEmptySpamItem.setVisible(mAccount != null && mFolder != null && mAccount.supportsCapability(AccountCapabilities.EMPTY_SPAM) && mFolder.isType(FolderType.SPAM) && mFolder.totalCount > 0 && (mController.getConversationListCursor() == null || mController.getConversationListCursor().getCount() > 0)); } } public boolean onPrepareOptionsMenu(Menu menu) { // We start out with every option enabled. Based on the current view, we disable actions // that are possible. LogUtils.d(LOG_TAG, "ActionBarView.onPrepareOptionsMenu()."); if (mController.shouldHideMenuItems()) { // Shortcut: hide all menu items if the drawer is shown final int size = menu.size(); for (int i = 0; i < size; i++) { final MenuItem item = menu.getItem(i); item.setVisible(false); } return false; } validateVolatileMenuOptionVisibility(); switch (getMode()) { case ViewMode.CONVERSATION: case ViewMode.SEARCH_RESULTS_CONVERSATION: // We update the ActionBar options when we are entering conversation view because // waiting for the AbstractConversationViewFragment to do it causes duplicate icons // to show up during the time between the conversation is selected and the fragment // is added. setConversationModeOptions(menu); break; case ViewMode.CONVERSATION_LIST: // Show search if the account supports it Utils.setMenuItemVisibility(menu, R.id.search, mAccount.supportsSearch()); break; case ViewMode.SEARCH_RESULTS_LIST: // Hide compose and search Utils.setMenuItemVisibility(menu, R.id.compose, false); Utils.setMenuItemVisibility(menu, R.id.search, false); break; } return false; } /** * Put the ActionBar in List navigation mode. */ private void showNavList() { setTitleModeFlags(ActionBar.DISPLAY_SHOW_TITLE); setFolderAndAccount(); } private void setTitle(String title) { if (!TextUtils.equals(title, mActionBar.getTitle())) { mActionBar.setTitle(title); } } /** * Set the actionbar mode to empty: no title, no subtitle, no custom view. */ protected void setEmptyMode() { // Disable title/subtitle and the custom view by setting the bitmask to all off. setTitleModeFlags(0); } /** * Removes the back button from being shown */ public void removeBackButton() { if (mActionBar == null) { return; } // Remove the back button but continue showing an icon. final int mask = ActionBar.DISPLAY_HOME_AS_UP | ActionBar.DISPLAY_SHOW_HOME; mActionBar.setDisplayOptions(ActionBar.DISPLAY_SHOW_HOME, mask); mActionBar.setHomeButtonEnabled(false); } public void setBackButton() { if (mActionBar == null) { return; } // Show home as up, and show an icon. final int mask = ActionBar.DISPLAY_HOME_AS_UP | ActionBar.DISPLAY_SHOW_HOME; mActionBar.setDisplayOptions(mask, mask); mActionBar.setHomeButtonEnabled(true); } @Override public boolean onQueryTextSubmit(String query) { if (mSearch != null) { MenuItemCompat.collapseActionView(mSearch); mSearchWidget.setQuery("", false); } mController.executeSearch(query.trim()); return true; } @Override public boolean onQueryTextChange(String newText) { return false; } // Next two methods are called when search suggestions are clicked. @Override public boolean onSuggestionSelect(int position) { return onSuggestionClick(position); } @Override public boolean onSuggestionClick(int position) { final Cursor c = mSearchWidget.getSuggestionsAdapter().getCursor(); final boolean haveValidQuery = (c != null) && c.moveToPosition(position); if (!haveValidQuery) { LogUtils.d(LOG_TAG, "onSuggestionClick: Couldn't get a search query"); // We haven't handled this query, but the default behavior will // leave EXTRA_ACCOUNT un-populated, leading to a crash. So claim // that we have handled the event. return true; } collapseSearch(); // what is in the text field String queryText = mSearchWidget.getQuery().toString(); // What the suggested query is String query = c.getString(c.getColumnIndex(SearchManager.SUGGEST_COLUMN_TEXT_1)); // If the text the user typed in is a prefix of what is in the search // widget suggestion query, just take the search widget suggestion // query. Otherwise, it is a suffix and we want to remove matching // prefix portions. if (!TextUtils.isEmpty(queryText) && query.indexOf(queryText) != 0) { final int queryTokenIndex = queryText .lastIndexOf(SearchRecentSuggestionsProvider.QUERY_TOKEN_SEPARATOR); if (queryTokenIndex > -1) { queryText = queryText.substring(0, queryTokenIndex); } // Since we auto-complete on each token in a query, if the query the // user typed up until the last token is a substring of the // suggestion they click, make sure we don't double include the // query text. For example: // user types john, that matches john palo alto // User types john p, that matches john john palo alto // Remove the first john // Only do this if we have multiple query tokens. if (queryTokenIndex > -1 && !TextUtils.isEmpty(query) && query.contains(queryText) && queryText.length() < query.length()) { int start = query.indexOf(queryText); query = query.substring(0, start) + query.substring(start + queryText.length()); } } mController.executeSearch(query.trim()); return true; } /** * Uses the current state to update the current folder {@link #mFolder} and the current * account {@link #mAccount} shown in the actionbar. Also updates the actionbar subtitle to * momentarily display the unread count if it has changed. */ private void setFolderAndAccount() { // Very little can be done if the actionbar or activity is null. if (mActionBar == null || mActivity == null) { return; } if (ViewMode.isWaitingForSync(getMode())) { // Account is not synced: clear title and update the subtitle. setTitle(""); return; } // Check if we should be changing the actionbar at all, and back off if not. final boolean isShowingFolder = mIsOnTablet || ViewMode.isListMode(getMode()); if (!isShowingFolder) { // It isn't necessary to set the title in this case, as the title view will // be hidden return; } if (mFolder == null) { // Clear the action bar title. We don't want the app name to be shown while // waiting for the folder query to finish setTitle(""); return; } setTitle(mFolder.name); } /** * Notify that the folder has changed. */ public void onFolderUpdated(Folder folder) { if (folder == null) { return; } /** True if we are changing folders. */ final boolean changingFolders = (mFolder == null || !mFolder.equals(folder)); mFolder = folder; setFolderAndAccount(); final ConversationListContext listContext = mController == null ? null : mController.getCurrentListContext(); if (changingFolders && !ConversationListContext.isSearchResult(listContext)) { closeSearchField(); } // make sure that we re-validate the optional menu items validateVolatileMenuOptionVisibility(); } @Override public boolean onMenuItemActionExpand(MenuItem item) { // Do nothing. Required as part of the interface, we ar only interested in // onMenuItemActionCollapse(MenuItem). // Have to return true here. Unlike other callbacks, the return value here is whether // we want to suppress the action (rather than consume the action). We don't want to // suppress the action. return true; } @Override public boolean onMenuItemActionCollapse(MenuItem item) { // Have to return true here. Unlike other callbacks, the return value // here is whether we want to suppress the action (rather than consume the action). We // don't want to suppress the action. return true; } /** * Sets the actionbar mode: Pass it an integer which contains each of these values, perhaps * OR'd together: {@link ActionBar#DISPLAY_SHOW_CUSTOM} and * {@link ActionBar#DISPLAY_SHOW_TITLE}. To disable all, pass a zero. * @param enabledFlags */ private void setTitleModeFlags(int enabledFlags) { final int mask = ActionBar.DISPLAY_SHOW_TITLE | ActionBar.DISPLAY_SHOW_CUSTOM; mActionBar.setDisplayOptions(enabledFlags, mask); } public void setCurrentConversation(Conversation conversation) { mCurrentConversation = conversation; } //We need to do this here instead of in the fragment public void setConversationModeOptions(Menu menu) { if (mCurrentConversation == null) { return; } final boolean showMarkImportant = !mCurrentConversation.isImportant(); Utils.setMenuItemVisibility(menu, R.id.mark_important, showMarkImportant && mAccount.supportsCapability(UIProvider.AccountCapabilities.MARK_IMPORTANT)); Utils.setMenuItemVisibility(menu, R.id.mark_not_important, !showMarkImportant && mAccount.supportsCapability(UIProvider.AccountCapabilities.MARK_IMPORTANT)); final boolean isOutbox = mFolder.isType(FolderType.OUTBOX); final boolean showDiscardOutbox = mFolder != null && isOutbox && mCurrentConversation.sendingState == UIProvider.ConversationSendingState.SEND_ERROR; Utils.setMenuItemVisibility(menu, R.id.discard_outbox, showDiscardOutbox); final boolean showDelete = !isOutbox && mFolder != null && mFolder.supportsCapability(UIProvider.FolderCapabilities.DELETE); Utils.setMenuItemVisibility(menu, R.id.delete, showDelete); // We only want to show the discard drafts menu item if we are not showing the delete menu // item, and the current folder is a draft folder and the account supports discarding // drafts for a conversation final boolean showDiscardDrafts = !showDelete && mFolder != null && mFolder.isDraft() && mAccount.supportsCapability(AccountCapabilities.DISCARD_CONVERSATION_DRAFTS); Utils.setMenuItemVisibility(menu, R.id.discard_drafts, showDiscardDrafts); final boolean archiveVisible = mAccount.supportsCapability(AccountCapabilities.ARCHIVE) && mFolder != null && mFolder.supportsCapability(FolderCapabilities.ARCHIVE) && !mFolder.isTrash(); Utils.setMenuItemVisibility(menu, R.id.archive, archiveVisible); Utils.setMenuItemVisibility(menu, R.id.remove_folder, !archiveVisible && mFolder != null && mFolder.supportsCapability(FolderCapabilities.CAN_ACCEPT_MOVED_MESSAGES) && !mFolder.isProviderFolder() && mAccount.supportsCapability(AccountCapabilities.ARCHIVE)); Utils.setMenuItemVisibility(menu, R.id.move_to, mFolder != null && mFolder.supportsCapability(FolderCapabilities.ALLOWS_REMOVE_CONVERSATION)); Utils.setMenuItemVisibility(menu, R.id.move_to_inbox, mFolder != null && mFolder.supportsCapability(FolderCapabilities.ALLOWS_MOVE_TO_INBOX)); Utils.setMenuItemVisibility(menu, R.id.change_folders, mAccount.supportsCapability(UIProvider.AccountCapabilities.MULTIPLE_FOLDERS_PER_CONV)); final MenuItem removeFolder = menu.findItem(R.id.remove_folder); if (mFolder != null && removeFolder != null) { removeFolder .setTitle(mActivity.getApplicationContext().getString(R.string.remove_folder, mFolder.name)); } Utils.setMenuItemVisibility(menu, R.id.report_spam, mAccount.supportsCapability(AccountCapabilities.REPORT_SPAM) && mFolder != null && mFolder.supportsCapability(FolderCapabilities.REPORT_SPAM) && !mCurrentConversation.spam); Utils.setMenuItemVisibility(menu, R.id.mark_not_spam, mAccount.supportsCapability(AccountCapabilities.REPORT_SPAM) && mFolder != null && mFolder.supportsCapability(FolderCapabilities.MARK_NOT_SPAM) && mCurrentConversation.spam); Utils.setMenuItemVisibility(menu, R.id.report_phishing, mAccount.supportsCapability(AccountCapabilities.REPORT_PHISHING) && mFolder != null && mFolder.supportsCapability(FolderCapabilities.REPORT_PHISHING) && !mCurrentConversation.phishing); Utils.setMenuItemVisibility(menu, R.id.mute, mAccount.supportsCapability(AccountCapabilities.MUTE) && mFolder != null && mFolder.supportsCapability(FolderCapabilities.DESTRUCTIVE_MUTE) && !mCurrentConversation.muted); } public void setViewModeController(ViewMode viewModeController) { mViewModeController = viewModeController; mViewModeController.addListener(this); } public Context getContext() { return mContext; } }