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.Fragment; import android.app.FragmentManager; import android.app.FragmentTransaction; import android.content.Intent; import android.net.Uri; import android.os.Bundle; import android.support.v4.widget.DrawerLayout; import android.view.Gravity; import android.widget.FrameLayout; import android.widget.ListView; import com.android.mail.ConversationListContext; import com.android.exchange.R; import com.android.mail.providers.Conversation; import com.android.mail.providers.Folder; import com.android.mail.providers.UIProvider.ConversationListIcon; import com.android.mail.utils.LogUtils; import com.android.mail.utils.Utils; /** * Controller for two-pane Mail activity. Two Pane is used for tablets, where screen real estate * abounds. */ public final class TwoPaneController extends AbstractActivityController { private static final String SAVED_MISCELLANEOUS_VIEW = "saved-miscellaneous-view"; private static final String SAVED_MISCELLANEOUS_VIEW_TRANSACTION_ID = "saved-miscellaneous-view-transaction-id"; private TwoPaneLayout mLayout; private Conversation mConversationToShow; /** * Used to determine whether onViewModeChanged should skip a potential * fragment transaction that would remove a miscellaneous view. */ private boolean mSavedMiscellaneousView = false; public TwoPaneController(MailActivity activity, ViewMode viewMode) { super(activity, viewMode); } /** * Display the conversation list fragment. */ private void initializeConversationListFragment() { if (Intent.ACTION_SEARCH.equals(mActivity.getIntent().getAction())) { if (shouldEnterSearchConvMode()) { mViewMode.enterSearchResultsConversationMode(); } else { mViewMode.enterSearchResultsListMode(); } } renderConversationList(); } /** * Render the conversation list in the correct pane. */ private void renderConversationList() { if (mActivity == null) { return; } FragmentTransaction fragmentTransaction = mActivity.getFragmentManager().beginTransaction(); // Use cross fading animation. fragmentTransaction.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE); final Fragment conversationListFragment = ConversationListFragment.newInstance(mConvListContext); fragmentTransaction.replace(R.id.conversation_list_pane, conversationListFragment, TAG_CONVERSATION_LIST); fragmentTransaction.commitAllowingStateLoss(); } @Override public boolean doesActionChangeConversationListVisibility(final int action) { if (action == R.id.settings || action == R.id.compose || action == R.id.help_info_menu_item || action == R.id.manage_folders_item || action == R.id.folder_options || action == R.id.feedback_menu_item) { return true; } return false; } @Override protected boolean isConversationListVisible() { return !mLayout.isConversationListCollapsed(); } @Override public void showConversationList(ConversationListContext listContext) { super.showConversationList(listContext); initializeConversationListFragment(); } @Override public boolean onCreate(Bundle savedState) { mActivity.setContentView(R.layout.two_pane_activity); mDrawerContainer = (DrawerLayout) mActivity.findViewById(R.id.drawer_container); mDrawerPullout = mDrawerContainer.findViewById(R.id.content_pane); mLayout = (TwoPaneLayout) mActivity.findViewById(R.id.two_pane_activity); if (mLayout == null) { // We need the layout for everything. Crash/Return early if it is null. LogUtils.wtf(LOG_TAG, "mLayout is null!"); return false; } mLayout.setController(this, Intent.ACTION_SEARCH.equals(mActivity.getIntent().getAction())); mLayout.setDrawerLayout(mDrawerContainer); if (savedState != null) { mSavedMiscellaneousView = savedState.getBoolean(SAVED_MISCELLANEOUS_VIEW, false); mMiscellaneousViewTransactionId = savedState.getInt(SAVED_MISCELLANEOUS_VIEW_TRANSACTION_ID, -1); } // 2-pane layout is the main listener of view mode changes, and issues secondary // notifications upon animation completion: // (onConversationVisibilityChanged, onConversationListVisibilityChanged) mViewMode.addListener(mLayout); return super.onCreate(savedState); } @Override public void onSaveInstanceState(Bundle outState) { super.onSaveInstanceState(outState); outState.putBoolean(SAVED_MISCELLANEOUS_VIEW, mMiscellaneousViewTransactionId >= 0); outState.putInt(SAVED_MISCELLANEOUS_VIEW_TRANSACTION_ID, mMiscellaneousViewTransactionId); } @Override public void onWindowFocusChanged(boolean hasFocus) { if (hasFocus && !mLayout.isConversationListCollapsed()) { // The conversation list is visible. informCursorVisiblity(true); } } @Override public void onFolderSelected(Folder folder) { // It's possible that we are not in conversation list mode if (mViewMode.getMode() != ViewMode.CONVERSATION_LIST) { mViewMode.enterConversationListMode(); } if (folder.parent != Uri.EMPTY) { // Show the up affordance when digging into child folders. mActionBarView.setBackButton(); } setHierarchyFolder(folder); super.onFolderSelected(folder); } @Override public void onViewModeChanged(int newMode) { if (!mSavedMiscellaneousView && mMiscellaneousViewTransactionId >= 0) { final FragmentManager fragmentManager = mActivity.getFragmentManager(); fragmentManager.popBackStackImmediate(mMiscellaneousViewTransactionId, FragmentManager.POP_BACK_STACK_INCLUSIVE); mMiscellaneousViewTransactionId = -1; } mSavedMiscellaneousView = false; super.onViewModeChanged(newMode); if (newMode != ViewMode.WAITING_FOR_ACCOUNT_INITIALIZATION) { // Clear the wait fragment hideWaitForInitialization(); } // In conversation mode, if the conversation list is not visible, then the user cannot // see the selected conversations. Disable the CAB mode while leaving the selected set // untouched. // When the conversation list is made visible again, try to enable the CAB // mode if any conversations are selected. if (newMode == ViewMode.CONVERSATION || newMode == ViewMode.CONVERSATION_LIST || ViewMode.isAdMode(newMode)) { enableOrDisableCab(); } } @Override public void onConversationVisibilityChanged(boolean visible) { super.onConversationVisibilityChanged(visible); if (!visible) { mPagerController.hide(false /* changeVisibility */); } else if (mConversationToShow != null) { mPagerController.show(mAccount, mFolder, mConversationToShow, false /* changeVisibility */); mConversationToShow = null; } } @Override public void onConversationListVisibilityChanged(boolean visible) { super.onConversationListVisibilityChanged(visible); enableOrDisableCab(); } @Override public void resetActionBarIcon() { if (isDrawerEnabled()) { return; } // On two-pane, the back button is only removed in the conversation list mode for top level // folders, and shown for every other condition. if ((mViewMode.isListMode() && (mFolder == null || mFolder.parent == null || mFolder.parent == Uri.EMPTY)) || mViewMode.isWaitingForSync()) { mActionBarView.removeBackButton(); } else { mActionBarView.setBackButton(); } } /** * Enable or disable the CAB mode based on the visibility of the conversation list fragment. */ private void enableOrDisableCab() { if (mLayout.isConversationListCollapsed()) { disableCabMode(); } else { enableCabMode(); } } @Override public void onSetPopulated(ConversationSelectionSet set) { super.onSetPopulated(set); boolean showSenderImage = (mAccount.settings.convListIcon == ConversationListIcon.SENDER_IMAGE); if (!showSenderImage && mViewMode.isListMode()) { getConversationListFragment().setChoiceNone(); } } @Override public void onSetEmpty() { super.onSetEmpty(); boolean showSenderImage = (mAccount.settings.convListIcon == ConversationListIcon.SENDER_IMAGE); if (!showSenderImage && mViewMode.isListMode()) { getConversationListFragment().revertChoiceMode(); } } @Override protected void showConversation(Conversation conversation, boolean inLoaderCallbacks) { super.showConversation(conversation, inLoaderCallbacks); // 2-pane can ignore inLoaderCallbacks because it doesn't use // FragmentManager.popBackStack(). if (mActivity == null) { return; } if (conversation == null) { handleBackPress(); return; } // If conversation list is not visible, then the user cannot see the CAB mode, so exit it. // This is needed here (in addition to during viewmode changes) because orientation changes // while viewing a conversation don't change the viewmode: the mode stays // ViewMode.CONVERSATION and yet the conversation list goes in and out of visibility. enableOrDisableCab(); // When a mode change is required, wait for onConversationVisibilityChanged(), the signal // that the mode change animation has finished, before rendering the conversation. mConversationToShow = conversation; final int mode = mViewMode.getMode(); LogUtils.i(LOG_TAG, "IN TPC.showConv, oldMode=%s conv=%s", mode, mConversationToShow); if (mode == ViewMode.SEARCH_RESULTS_LIST || mode == ViewMode.SEARCH_RESULTS_CONVERSATION) { mViewMode.enterSearchResultsConversationMode(); } else { mViewMode.enterConversationMode(); } // load the conversation immediately if we're already in conversation mode if (!mLayout.isModeChangePending()) { onConversationVisibilityChanged(true); } else { LogUtils.i(LOG_TAG, "TPC.showConversation will wait for TPL.animationEnd to show!"); } } @Override public void setCurrentConversation(Conversation conversation) { // Order is important! We want to calculate different *before* the superclass changes // mCurrentConversation, so before super.setCurrentConversation(). final long oldId = mCurrentConversation != null ? mCurrentConversation.id : -1; final long newId = conversation != null ? conversation.id : -1; final boolean different = oldId != newId; // This call might change mCurrentConversation. super.setCurrentConversation(conversation); final ConversationListFragment convList = getConversationListFragment(); if (convList != null && conversation != null) { convList.setSelected(conversation.position, different); } } @Override public void showWaitForInitialization() { super.showWaitForInitialization(); FragmentTransaction fragmentTransaction = mActivity.getFragmentManager().beginTransaction(); fragmentTransaction.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN); fragmentTransaction.replace(R.id.conversation_list_pane, getWaitFragment(), TAG_WAIT); fragmentTransaction.commitAllowingStateLoss(); } @Override protected void hideWaitForInitialization() { final WaitFragment waitFragment = getWaitFragment(); if (waitFragment == null) { // We aren't showing a wait fragment: nothing to do return; } // Remove the existing wait fragment from the back stack. final FragmentTransaction fragmentTransaction = mActivity.getFragmentManager().beginTransaction(); fragmentTransaction.remove(waitFragment); fragmentTransaction.commitAllowingStateLoss(); super.hideWaitForInitialization(); if (mViewMode.isWaitingForSync()) { // We should come out of wait mode and display the account inbox. loadAccountInbox(); } } /** * Up works as follows: * 1) If the user is in a conversation and: * a) the conversation list is hidden (portrait mode), shows the conv list and * stays in conversation view mode. * b) the conversation list is shown, goes back to conversation list mode. * 2) If the user is in search results, up exits search. * mode and returns the user to whatever view they were in when they began search. * 3) If the user is in conversation list mode, there is no up. */ @Override public boolean handleUpPress() { int mode = mViewMode.getMode(); if (mode == ViewMode.CONVERSATION || mViewMode.isAdMode()) { handleBackPress(); } else if (mode == ViewMode.SEARCH_RESULTS_CONVERSATION) { if (mLayout.isConversationListCollapsed() || (ConversationListContext.isSearchResult(mConvListContext) && !Utils.showTwoPaneSearchResults(mActivity.getApplicationContext()))) { handleBackPress(); } else { mActivity.finish(); } } else if (mode == ViewMode.SEARCH_RESULTS_LIST) { mActivity.finish(); } else if (mode == ViewMode.CONVERSATION_LIST || mode == ViewMode.WAITING_FOR_ACCOUNT_INITIALIZATION) { final boolean isTopLevel = (mFolder == null) || (mFolder.parent == Uri.EMPTY); if (isTopLevel) { // Show the drawer toggleDrawerState(); } else { popView(true); } } return true; } @Override public boolean handleBackPress() { // Clear any visible undo bars. mToastBar.hide(false, false /* actionClicked */); popView(false); return true; } /** * Pops the "view stack" to the last screen the user was viewing. * * @param preventClose Whether to prevent closing the app if the stack is empty. */ protected void popView(boolean preventClose) { // If the user is in search query entry mode, or the user is viewing // search results, exit // the mode. int mode = mViewMode.getMode(); if (mode == ViewMode.SEARCH_RESULTS_LIST) { mActivity.finish(); } else if (mode == ViewMode.CONVERSATION || mViewMode.isAdMode()) { // Go to conversation list. mViewMode.enterConversationListMode(); } else if (mode == ViewMode.SEARCH_RESULTS_CONVERSATION) { mViewMode.enterSearchResultsListMode(); } else { // The Folder List fragment can be null for monkeys where we get a back before the // folder list has had a chance to initialize. final FolderListFragment folderList = getFolderListFragment(); if (mode == ViewMode.CONVERSATION_LIST && folderList != null && mFolder != null && mFolder.parent != Uri.EMPTY) { // If the user navigated via the left folders list into a child folder, // back should take the user up to the parent folder's conversation list. navigateUpFolderHierarchy(); // Otherwise, if we are in the conversation list but not in the default // inbox and not on expansive layouts, we want to switch back to the default // inbox. This fixes b/9006969 so that on smaller tablets where we have this // hybrid one and two-pane mode, we will return to the inbox. On larger tablets, // we will instead exit the app. } else { // Don't think mLayout could be null but checking just in case if (mLayout == null) { LogUtils.wtf(LOG_TAG, new Throwable(), "mLayout is null"); } // mFolder could be null if back is pressed while account is waiting for sync final boolean shouldLoadInbox = mode == ViewMode.CONVERSATION_LIST && mFolder != null && !mFolder.folderUri.equals(mAccount.settings.defaultInbox) && mLayout != null && !mLayout.isExpansiveLayout(); if (shouldLoadInbox) { loadAccountInbox(); } else if (!preventClose) { // There is nothing else to pop off the stack. mActivity.finish(); } } } } @Override public void exitSearchMode() { final int mode = mViewMode.getMode(); if (mode == ViewMode.SEARCH_RESULTS_LIST || (mode == ViewMode.SEARCH_RESULTS_CONVERSATION && Utils.showTwoPaneSearchResults(mActivity.getApplicationContext()))) { mActivity.finish(); } } @Override public boolean shouldShowFirstConversation() { return Intent.ACTION_SEARCH.equals(mActivity.getIntent().getAction()) && shouldEnterSearchConvMode(); } @Override public void onUndoAvailable(ToastBarOperation op) { final int mode = mViewMode.getMode(); final ConversationListFragment convList = getConversationListFragment(); repositionToastBar(op); switch (mode) { case ViewMode.SEARCH_RESULTS_LIST: case ViewMode.CONVERSATION_LIST: case ViewMode.SEARCH_RESULTS_CONVERSATION: case ViewMode.CONVERSATION: if (convList != null) { mToastBar.show(getUndoClickedListener(convList.getAnimatedAdapter()), 0, Utils.convertHtmlToPlainText(op.getDescription(mActivity.getActivityContext())), true, /* showActionIcon */ R.string.undo, true, /* replaceVisibleToast */ op); } } } public void repositionToastBar(ToastBarOperation op) { repositionToastBar(op.isBatchUndo()); } /** * Set the toast bar's layout params to position it in the right place * depending the current view mode. * * @param convModeShowInList if we're in conversation mode, should the toast * bar appear over the list? no effect when not in conversation mode. */ private void repositionToastBar(boolean convModeShowInList) { final int mode = mViewMode.getMode(); final FrameLayout.LayoutParams params = (FrameLayout.LayoutParams) mToastBar.getLayoutParams(); switch (mode) { case ViewMode.SEARCH_RESULTS_LIST: case ViewMode.CONVERSATION_LIST: params.width = mLayout.computeConversationListWidth() - params.leftMargin - params.rightMargin; params.gravity = Gravity.BOTTOM | Gravity.RIGHT; mToastBar.setLayoutParams(params); break; case ViewMode.SEARCH_RESULTS_CONVERSATION: case ViewMode.CONVERSATION: if (convModeShowInList && !mLayout.isConversationListCollapsed()) { // Show undo bar in the conversation list. params.gravity = Gravity.BOTTOM | Gravity.LEFT; params.width = mLayout.computeConversationListWidth() - params.leftMargin - params.rightMargin; mToastBar.setLayoutParams(params); } else { // Show undo bar in the conversation. params.gravity = Gravity.BOTTOM | Gravity.RIGHT; params.width = mLayout.computeConversationWidth() - params.leftMargin - params.rightMargin; mToastBar.setLayoutParams(params); } break; } } @Override protected void hideOrRepositionToastBar(final boolean animated) { final int oldViewMode = mViewMode.getMode(); mLayout.postDelayed(new Runnable() { @Override public void run() { if (/* the touch did not open a conversation */oldViewMode == mViewMode.getMode() || /* animation has ended */!mToastBar.isAnimating()) { mToastBar.hide(animated, false /* actionClicked */); } else { // the touch opened a conversation, reposition undo bar repositionToastBar(mToastBar.getOperation()); } } }, /* Give time for ViewMode to change from the touch */ mContext.getResources().getInteger(R.integer.dismiss_undo_bar_delay_ms)); } @Override public void onError(final Folder folder, boolean replaceVisibleToast) { repositionToastBar(true /* convModeShowInList */); showErrorToast(folder, replaceVisibleToast); } @Override public boolean isDrawerEnabled() { return mLayout.isDrawerEnabled(); } @Override public int getFolderListViewChoiceMode() { // By default, we want to allow one item to be selected in the folder list return ListView.CHOICE_MODE_SINGLE; } private int mMiscellaneousViewTransactionId = -1; @Override public void launchFragment(final Fragment fragment, final int selectPosition) { final int containerViewId = TwoPaneLayout.MISCELLANEOUS_VIEW_ID; final FragmentManager fragmentManager = mActivity.getFragmentManager(); if (fragmentManager.findFragmentByTag(TAG_CUSTOM_FRAGMENT) == null) { final FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction(); fragmentTransaction.addToBackStack(null); fragmentTransaction.replace(containerViewId, fragment, TAG_CUSTOM_FRAGMENT); mMiscellaneousViewTransactionId = fragmentTransaction.commitAllowingStateLoss(); fragmentManager.executePendingTransactions(); } if (selectPosition >= 0) { getConversationListFragment().setRawSelected(selectPosition, true); } } }