RecentsViewTouchHandler.java revision ca9dddb3bf63cd25cbf09fdacd5e1d3b8933658c 
1/*
2 * Copyright (C) 2014 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 */
16
17package com.android.systemui.recents.views;
18
19import android.app.ActivityManager;
20import android.content.res.Configuration;
21import android.graphics.Point;
22import android.graphics.Rect;
23import android.view.InputDevice;
24import android.view.MotionEvent;
25import android.view.PointerIcon;
26import android.view.ViewConfiguration;
27import android.view.ViewDebug;
28
29import com.android.internal.policy.DividerSnapAlgorithm;
30import com.android.systemui.recents.Recents;
31import com.android.systemui.recents.RecentsConfiguration;
32import com.android.systemui.recents.events.EventBus;
33import com.android.systemui.recents.events.activity.ConfigurationChangedEvent;
34import com.android.systemui.recents.events.ui.HideIncompatibleAppOverlayEvent;
35import com.android.systemui.recents.events.ui.ShowIncompatibleAppOverlayEvent;
36import com.android.systemui.recents.events.ui.dragndrop.DragDropTargetChangedEvent;
37import com.android.systemui.recents.events.ui.dragndrop.DragEndEvent;
38import com.android.systemui.recents.events.ui.dragndrop.DragStartEvent;
39import com.android.systemui.recents.events.ui.dragndrop.DragStartInitializeDropTargetsEvent;
40import com.android.systemui.recents.misc.SystemServicesProxy;
41import com.android.systemui.recents.model.Task;
42import com.android.systemui.recents.model.TaskStack;
43
44import java.util.ArrayList;
45
46/**
47 * Represents the dock regions for each orientation.
48 */
49class DockRegion {
50    public static TaskStack.DockState[] PHONE_LANDSCAPE = {
51            // We only allow docking to the left in landscape for now on small devices
52            TaskStack.DockState.LEFT
53    };
54    public static TaskStack.DockState[] PHONE_PORTRAIT = {
55            // We only allow docking to the top for now on small devices
56            TaskStack.DockState.TOP
57    };
58    public static TaskStack.DockState[] TABLET_LANDSCAPE = {
59            TaskStack.DockState.LEFT,
60            TaskStack.DockState.RIGHT
61    };
62    public static TaskStack.DockState[] TABLET_PORTRAIT = PHONE_PORTRAIT;
63}
64
65/**
66 * Handles touch events for a RecentsView.
67 */
68public class RecentsViewTouchHandler {
69
70    private RecentsView mRv;
71
72    @ViewDebug.ExportedProperty(deepExport=true, prefix="drag_task")
73    private Task mDragTask;
74    @ViewDebug.ExportedProperty(deepExport=true, prefix="drag_task_view_")
75    private TaskView mTaskView;
76
77    @ViewDebug.ExportedProperty(category="recents")
78    private Point mTaskViewOffset = new Point();
79    @ViewDebug.ExportedProperty(category="recents")
80    private Point mDownPos = new Point();
81    @ViewDebug.ExportedProperty(category="recents")
82    private boolean mDragRequested;
83    @ViewDebug.ExportedProperty(category="recents")
84    private boolean mIsDragging;
85    private float mDragSlop;
86    private int mDeviceId = -1;
87
88    private DropTarget mLastDropTarget;
89    private DividerSnapAlgorithm mDividerSnapAlgorithm;
90    private ArrayList<DropTarget> mDropTargets = new ArrayList<>();
91    private ArrayList<TaskStack.DockState> mVisibleDockStates = new ArrayList<>();
92
93    public RecentsViewTouchHandler(RecentsView rv) {
94        mRv = rv;
95        mDragSlop = ViewConfiguration.get(rv.getContext()).getScaledTouchSlop();
96        updateSnapAlgorithm();
97    }
98
99    private void updateSnapAlgorithm() {
100        Rect insets = new Rect();
101        SystemServicesProxy.getInstance(mRv.getContext()).getStableInsets(insets);
102        mDividerSnapAlgorithm = DividerSnapAlgorithm.create(mRv.getContext(), insets);
103    }
104
105    /**
106     * Registers a new drop target for the current drag only.
107     */
108    public void registerDropTargetForCurrentDrag(DropTarget target) {
109        mDropTargets.add(target);
110    }
111
112    /**
113     * Returns the preferred dock states for the current orientation.
114     */
115    public TaskStack.DockState[] getDockStatesForCurrentOrientation() {
116        boolean isLandscape = mRv.getResources().getConfiguration().orientation ==
117                Configuration.ORIENTATION_LANDSCAPE;
118        RecentsConfiguration config = Recents.getConfiguration();
119        if (config.isLargeScreen) {
120            return isLandscape ? DockRegion.TABLET_LANDSCAPE : DockRegion.TABLET_PORTRAIT;
121        } else {
122            return isLandscape ? DockRegion.PHONE_LANDSCAPE : DockRegion.PHONE_PORTRAIT;
123        }
124    }
125
126    /**
127     * Returns the set of visible dock states for this current drag.
128     */
129    public ArrayList<TaskStack.DockState> getVisibleDockStates() {
130        return mVisibleDockStates;
131    }
132
133    /** Touch preprocessing for handling below */
134    public boolean onInterceptTouchEvent(MotionEvent ev) {
135        handleTouchEvent(ev);
136        return mDragRequested;
137    }
138
139    /** Handles touch events once we have intercepted them */
140    public boolean onTouchEvent(MotionEvent ev) {
141        handleTouchEvent(ev);
142        return mDragRequested;
143    }
144
145    /**** Events ****/
146
147    public final void onBusEvent(DragStartEvent event) {
148        SystemServicesProxy ssp = Recents.getSystemServices();
149        mRv.getParent().requestDisallowInterceptTouchEvent(true);
150        mDragRequested = true;
151        // We defer starting the actual drag handling until the user moves past the drag slop
152        mIsDragging = false;
153        mDragTask = event.task;
154        mTaskView = event.taskView;
155        mDropTargets.clear();
156
157        int[] recentsViewLocation = new int[2];
158        mRv.getLocationInWindow(recentsViewLocation);
159        mTaskViewOffset.set(mTaskView.getLeft() - recentsViewLocation[0] + event.tlOffset.x,
160                mTaskView.getTop() - recentsViewLocation[1] + event.tlOffset.y);
161        float x = mDownPos.x - mTaskViewOffset.x;
162        float y = mDownPos.y - mTaskViewOffset.y;
163        mTaskView.setTranslationX(x);
164        mTaskView.setTranslationY(y);
165
166        mVisibleDockStates.clear();
167        if (ActivityManager.supportsMultiWindow() && !ssp.hasDockedTask()
168                && mDividerSnapAlgorithm.isSplitScreenFeasible()) {
169            Recents.logDockAttempt(mRv.getContext(), event.task.getTopComponent(),
170                    event.task.resizeMode);
171            if (!event.task.isDockable) {
172                EventBus.getDefault().send(new ShowIncompatibleAppOverlayEvent());
173            } else {
174                // Add the dock state drop targets (these take priority)
175                TaskStack.DockState[] dockStates = getDockStatesForCurrentOrientation();
176                for (TaskStack.DockState dockState : dockStates) {
177                    registerDropTargetForCurrentDrag(dockState);
178                    dockState.update(mRv.getContext());
179                    mVisibleDockStates.add(dockState);
180                }
181            }
182        }
183
184        // Request other drop targets to register themselves
185        EventBus.getDefault().send(new DragStartInitializeDropTargetsEvent(event.task,
186                event.taskView, this));
187        if (mDeviceId != -1) {
188            InputDevice.getDevice(mDeviceId).setPointerType(PointerIcon.TYPE_GRABBING);
189        }
190    }
191
192    public final void onBusEvent(DragEndEvent event) {
193        if (!mDragTask.isDockable) {
194            EventBus.getDefault().send(new HideIncompatibleAppOverlayEvent());
195        }
196        mDragRequested = false;
197        mDragTask = null;
198        mTaskView = null;
199        mLastDropTarget = null;
200    }
201
202    public final void onBusEvent(ConfigurationChangedEvent event) {
203        if (event.fromDisplayDensityChange || event.fromDeviceOrientationChange) {
204            updateSnapAlgorithm();
205        }
206    }
207
208    /**
209     * Handles dragging touch events
210     */
211    private void handleTouchEvent(MotionEvent ev) {
212        int action = ev.getActionMasked();
213        switch (action) {
214            case MotionEvent.ACTION_DOWN:
215                mDownPos.set((int) ev.getX(), (int) ev.getY());
216                mDeviceId = ev.getDeviceId();
217                break;
218            case MotionEvent.ACTION_MOVE: {
219                float evX = ev.getX();
220                float evY = ev.getY();
221                float x = evX - mTaskViewOffset.x;
222                float y = evY - mTaskViewOffset.y;
223
224                if (mDragRequested) {
225                    if (!mIsDragging) {
226                        mIsDragging = Math.hypot(evX - mDownPos.x, evY - mDownPos.y) > mDragSlop;
227                    }
228                    if (mIsDragging) {
229                        int width = mRv.getMeasuredWidth();
230                        int height = mRv.getMeasuredHeight();
231
232                        DropTarget currentDropTarget = null;
233
234                        // Give priority to the current drop target to retain the touch handling
235                        if (mLastDropTarget != null) {
236                            if (mLastDropTarget.acceptsDrop((int) evX, (int) evY, width, height,
237                                    mRv.mSystemInsets, true /* isCurrentTarget */)) {
238                                currentDropTarget = mLastDropTarget;
239                            }
240                        }
241
242                        // Otherwise, find the next target to handle this event
243                        if (currentDropTarget == null) {
244                            for (DropTarget target : mDropTargets) {
245                                if (target.acceptsDrop((int) evX, (int) evY, width, height,
246                                        mRv.mSystemInsets, false /* isCurrentTarget */)) {
247                                    currentDropTarget = target;
248                                    break;
249                                }
250                            }
251                        }
252                        if (mLastDropTarget != currentDropTarget) {
253                            mLastDropTarget = currentDropTarget;
254                            EventBus.getDefault().send(new DragDropTargetChangedEvent(mDragTask,
255                                    currentDropTarget));
256                        }
257
258                    }
259
260                    mTaskView.setTranslationX(x);
261                    mTaskView.setTranslationY(y);
262                }
263                break;
264            }
265            case MotionEvent.ACTION_UP:
266            case MotionEvent.ACTION_CANCEL: {
267                if (mDragRequested) {
268                    boolean cancelled = action == MotionEvent.ACTION_CANCEL;
269                    if (cancelled) {
270                        EventBus.getDefault().send(new DragDropTargetChangedEvent(mDragTask, null));
271                    }
272                    EventBus.getDefault().send(new DragEndEvent(mDragTask, mTaskView,
273                            !cancelled ? mLastDropTarget : null));
274                    break;
275                }
276                mDeviceId = -1;
277            }
278        }
279    }
280}
281