Java tutorial
/* * Copyright (C) 2015 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.talkback.tutorial; import android.app.ActionBar; import android.app.Activity; import android.app.Fragment; import android.content.res.Resources; import android.os.Bundle; import android.os.Handler; import android.os.Looper; import android.support.v4.content.LocalBroadcastManager; import android.text.TextUtils; import android.view.LayoutInflater; import android.view.MenuItem; import android.view.View; import android.view.ViewGroup; import android.view.accessibility.AccessibilityEvent; import android.widget.ImageView; import android.widget.TextView; import android.widget.Toolbar; import com.android.talkback.R; import com.android.talkback.SpeechController; import com.android.talkback.contextmenu.MenuActionInterceptor; import com.android.talkback.contextmenu.MenuManager; import com.android.talkback.contextmenu.MenuTransformer; import com.android.talkback.controller.GestureActionMonitor; import com.android.talkback.tutorial.exercise.Exercise; import com.google.android.marvin.talkback.TalkBackService; public class TutorialLessonFragment extends Fragment implements View.OnClickListener, Exercise.ExerciseCallback, GestureActionMonitor.GestureActionListener { private static final int DELAY_BEFORE_ANNOUNCE_LESSON = 100; private static final int DELAY_BEFORE_AUTO_MOVE_TO_NEXT_LESSON = 1000; private TutorialController mTutorialController; private TutorialLesson mLesson; private TutorialLessonPage mPage; private Exercise mExercise; private int mCurrentPage; private TutorialNavigationCallback mCallback; private TextView mDescription; private SpeechController mSpeechController; private GestureActionMonitor mActionMonitor = new GestureActionMonitor(); private Handler mHandler = new Handler(Looper.getMainLooper()); public void setLesson(TutorialLesson lesson, int currentPage) { mLesson = lesson; mPage = mLesson.getLessonPage(currentPage); mCurrentPage = currentPage; mExercise = mPage.getExercise(); } public void setTutorialController(TutorialController tutorialController) { mTutorialController = tutorialController; } public void setTutorialNavigationCallback(TutorialNavigationCallback callback) { mCallback = callback; } @Override public void onCreate(Bundle instance) { super.onCreate(instance); setRetainInstance(true); setHasOptionsMenu(true); mExercise.setExerciseCallBack(this); TalkBackService service = TalkBackService.getInstance(); if (service != null) { mSpeechController = service.getSpeechController(); } mActionMonitor.setListener(this); } @Override public void onStart() { super.onStart(); MenuTransformer menuTransformer = mExercise.getContextMenuTransformer(); MenuActionInterceptor menuActionInterceptor = mExercise.getContextMenuActionInterceptor(); TalkBackService service = TalkBackService.getInstance(); if (service != null) { MenuManager menuManager = service.getMenuManager(); menuManager.setMenuTransformer(menuTransformer); menuManager.setMenuActionInterceptor(menuActionInterceptor); } // We need to post the announcements delayed in order to ensure that the view changed // event gets sent beforehand. This makes the TalkBack speech response flow more logical. Handler handler = new Handler(); handler.postDelayed(new Runnable() { @Override public void run() { View view = getView(); if (view == null) { // Something terrible has happened, e.g. the fragment is gone. return; } view.announceForAccessibility(getTitle()); view.announceForAccessibility(mPage.getSubtitle()); mDescription.sendAccessibilityEvent(AccessibilityEvent.TYPE_VIEW_ACCESSIBILITY_FOCUSED); } }, DELAY_BEFORE_ANNOUNCE_LESSON); mExercise.onInitialized(getActivity()); } @Override public void onStop() { super.onStop(); mExercise.clear(); TalkBackService service = TalkBackService.getInstance(); if (service != null) { service.getMenuManager().setMenuTransformer(null); service.getMenuManager().setMenuActionInterceptor(null); service.getSpeechController().interrupt(); } } @Override public void onResume() { super.onResume(); Activity activity = getActivity(); if (activity != null) { ActionBar actionBar = activity.getActionBar(); actionBar.setDisplayHomeAsUpEnabled(false); actionBar.setDisplayShowHomeEnabled(false); actionBar.setDisplayShowCustomEnabled(true); actionBar.setDisplayShowTitleEnabled(false); actionBar.setCustomView(R.layout.tutorial_action_bar); actionBar.getCustomView().findViewById(R.id.up).setOnClickListener(this); TextView title = (TextView) actionBar.getCustomView().findViewById(R.id.action_bar_title); title.setText(getTitle()); LocalBroadcastManager.getInstance(activity).registerReceiver(mActionMonitor, GestureActionMonitor.FILTER); } TalkBackService service = TalkBackService.getInstance(); if (service != null) { service.addEventListener(mExercise); } } private String getTitle() { if (!TextUtils.isEmpty(mPage.getTitle())) { return mPage.getTitle(); } else { return mLesson.getTitle(); } } @Override public void onPause() { super.onPause(); TalkBackService service = TalkBackService.getInstance(); if (service != null) { service.postRemoveEventListener(mExercise); } Activity activity = getActivity(); if (activity != null) { LocalBroadcastManager.getInstance(activity).unregisterReceiver(mActionMonitor); } mHandler.removeCallbacksAndMessages(null); } @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedState) { int layoutId; if (mExercise.needScrollableContainer()) { layoutId = R.layout.tutorial_lesson_fragment_scrollable; } else { layoutId = R.layout.tutorial_lesson_fragment; } View view = inflater.inflate(layoutId, container, false); mDescription = (TextView) view.findViewById(R.id.description); mDescription.setText(mPage.getDescription()); TextView subTitle = (TextView) view.findViewById(R.id.part_subtitle); subTitle.setText(mPage.getSubtitle()); TextView currentPage = (TextView) view.findViewById(R.id.current_page); TextView next = (TextView) view.findViewById(R.id.next); if (mCurrentPage < mLesson.getPagesCount() - 1) { next.setText(R.string.tutorial_next); currentPage.setVisibility(View.VISIBLE); currentPage.setText( getString(R.string.tutorial_page_number_of, mCurrentPage + 1, mLesson.getPagesCount() - 1)); } else if (mTutorialController.getNextLesson(mLesson) == null) { next.setText(R.string.tutorial_home); } else { next.setText(R.string.tutorial_next_lesson); } next.setOnClickListener(this); View previous = view.findViewById(R.id.previous_page); previous.setOnClickListener(this); previous.setContentDescription(getString(R.string.tutorial_previous)); ViewGroup contentContainer = (ViewGroup) view.findViewById(R.id.practice_area); View contentView = mPage.getExercise().getContentView(inflater, contentContainer); ViewGroup.LayoutParams params = new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT); contentContainer.addView(contentView, params); return view; } @Override public void onClick(View v) { switch (v.getId()) { case R.id.next: if (mCallback != null) { mCallback.onNextPageClicked(mLesson, mCurrentPage); } break; case R.id.previous_page: if (mCallback != null) { mCallback.onPreviousPageClicked(mLesson, mCurrentPage); } break; case R.id.up: mCallback.onNavigateUpClicked(); break; } } @Override public void onExerciseCompleted(boolean autoSwitchLesson, int completeMessageResId) { if (mSpeechController == null) { return; } SpeechController.UtteranceCompleteRunnable speechCallback = null; if (autoSwitchLesson) { speechCallback = new SpeechController.UtteranceCompleteRunnable() { @Override public void run(int status) { moveToNextPageWithDelay(DELAY_BEFORE_AUTO_MOVE_TO_NEXT_LESSON); } }; } notifyExerciseCompleted(speechCallback, completeMessageResId); } private void notifyExerciseCompleted(final SpeechController.UtteranceCompleteRunnable callback, final int completeMessageResId) { if (!isResumed()) { return; } mHandler.postDelayed(new Runnable() { @Override public void run() { mSpeechController.speak(getString(completeMessageResId), null, null, SpeechController.QUEUE_MODE_UNINTERRUPTIBLE, 0, 0, null, null, callback); } }, DELAY_BEFORE_AUTO_MOVE_TO_NEXT_LESSON); } private void moveToNextPageWithDelay(long delay) { if (!isResumed()) { return; } mHandler.postDelayed(new Runnable() { @Override public void run() { if (getActivity() != null) { mCallback.onNextPageClicked(mLesson, mCurrentPage); } } }, delay); } @Override public void onGestureAction(String action) { if (mExercise == null || TextUtils.isEmpty(action) || getActivity() == null) { return; } mExercise.onAction(getActivity(), action); } }