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.Activity; import android.app.Fragment; import android.content.ComponentName; import android.os.Build; import android.os.Bundle; import android.support.v4.os.BuildCompat; import android.text.TextUtils; import android.text.TextUtils.SimpleStringSplitter; import android.util.Log; import android.view.accessibility.AccessibilityEvent; import android.view.Gravity; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.Button; import android.widget.ListView; import com.android.talkback.R; import com.android.talkback.SpeechController; import com.android.utils.AccessibilityEventListener; import com.google.android.marvin.talkback.TalkBackService; import java.lang.reflect.Method; public class TutorialMainFragment extends Fragment implements AccessibilityEventListener { private static final String TUTORIAL_CLASS_NAME = AccessibilityTutorialActivity.class.getName(); private TutorialNavigationCallback mLessonSelectedCallback; private TutorialController mTutorialController; private HoverTrackingButton mOffButton; private HoverTrackingLinearLayout mParentLayout; private boolean mOtherViewHovered; public void setOnLessonSelectedCallback(TutorialNavigationCallback callback) { mLessonSelectedCallback = callback; } public void setTutorialController(TutorialController controller) { mTutorialController = controller; } @Override public void onCreate(Bundle savedState) { super.onCreate(savedState); setRetainInstance(true); } @Override public void onResume() { super.onResume(); Activity activity = getActivity(); if (activity != null) { activity.getActionBar().setDisplayHomeAsUpEnabled(false); activity.getActionBar().setDisplayShowTitleEnabled(true); activity.getActionBar().setDisplayShowCustomEnabled(false); } } @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedState) { View view = inflater.inflate(R.layout.tutorial_main_fragment, container, false); ListView lessonListView = (ListView) view.findViewById(R.id.list); LessonsAdapter adapter = new LessonsAdapter(getActivity(), mTutorialController.getTutorial(), mLessonSelectedCallback); lessonListView.setAdapter(adapter); mOffButton = (HoverTrackingButton) view.findViewById(R.id.offButton); mParentLayout = (HoverTrackingLinearLayout) view.findViewById(R.id.parentLayout); if (BuildCompat.isAtLeastN() && TalkBackService.getInstance() != null) { TalkBackService.getInstance().addEventListener(this); } else if (mOffButton != null) { mOffButton.setVisibility(View.GONE); } return view; } @Override public void onAccessibilityEvent(AccessibilityEvent event) { if (mOffButton == null || mParentLayout == null) { return; } // There are three types of areas that we're detecting: the button area, areas of the // activity that are a11y-focusable, and areas of the activity that are blank. // 1) The HoverTrackingButton keeps track of the button area. // 2) The HoverTrackingLinearLayout keeps track of blank activity areas. // 3) We use TYPE_VIEW_HOVER_ENTER to track a11y-focusable activity areas. // The user must begin and end the touch interaction within the Turn TalkBack Off button // without moving their finger into other areas of the activity in order to turn TB off. switch (event.getEventType()) { case AccessibilityEvent.TYPE_TOUCH_INTERACTION_START: mOtherViewHovered = false; mOffButton.clearTracking(); mParentLayout.clearTracking(); break; case AccessibilityEvent.TYPE_TOUCH_INTERACTION_END: if (mOffButton.didHoverEnter() && !mParentLayout.didHoverEnter() && !mOtherViewHovered) { if (TalkBackService.getInstance() != null) { TalkBackService.getInstance().disableTalkBack(); } } break; case AccessibilityEvent.TYPE_VIEW_HOVER_ENTER: CharSequence className = event.getClassName(); // Hovering over the button gives an event with TUTORIAL_CLASS_NAME class. // But empty areas of the activity should be tracked by HoverTrackingLinearLayout. if (className == null || !className.equals(TUTORIAL_CLASS_NAME)) { mOtherViewHovered = true; } break; } } }