RecentsViewTouchHandler.java revision 6519c1b0fe85c5f25115539e936e4333e8537098 
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.graphics.Point;
21import android.graphics.Rect;
22import android.view.InputDevice;
23import android.view.MotionEvent;
24import android.view.PointerIcon;
25import android.view.View;
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.events.EventBus;
32import com.android.systemui.recents.events.activity.ConfigurationChangedEvent;
33import com.android.systemui.recents.events.activity.HideRecentsEvent;
34import com.android.systemui.recents.events.ui.DismissAllTaskViewsEvent;
35import com.android.systemui.recents.events.ui.HideIncompatibleAppOverlayEvent;
36import com.android.systemui.recents.events.ui.ShowIncompatibleAppOverlayEvent;
37import com.android.systemui.recents.events.ui.dragndrop.DragDropTargetChangedEvent;
38import com.android.systemui.recents.events.ui.dragndrop.DragEndEvent;
39import com.android.systemui.recents.events.ui.dragndrop.DragStartEvent;
40import com.android.systemui.recents.events.ui.dragndrop.DragStartInitializeDropTargetsEvent;
41import com.android.systemui.recents.misc.SystemServicesProxy;
42import com.android.systemui.shared.recents.model.Task;
43import com.android.systemui.shared.recents.model.TaskStack;
44
45import java.util.ArrayList;
46
47/**
48 * Handles touch events for a RecentsView.
49 */
50public class RecentsViewTouchHandler {
51
52    private RecentsView mRv;
53
54    @ViewDebug.ExportedProperty(deepExport=true, prefix="drag_task")
55    private Task mDragTask;
56    @ViewDebug.ExportedProperty(deepExport=true, prefix="drag_task_view_")
57    private TaskView mTaskView;
58
59    @ViewDebug.ExportedProperty(category="recents")
60    private Point mTaskViewOffset = new Point();
61    @ViewDebug.ExportedProperty(category="recents")
62    private Point mDownPos = new Point();
63    @ViewDebug.ExportedProperty(category="recents")
64    private boolean mDragRequested;
65    @ViewDebug.ExportedProperty(category="recents")
66    private boolean mIsDragging;
67    private float mDragSlop;
68    private int mDeviceId = -1;
69
70    private DropTarget mLastDropTarget;
71    private DividerSnapAlgorithm mDividerSnapAlgorithm;
72    private ArrayList<DropTarget> mDropTargets = new ArrayList<>();
73    private ArrayList<DockState> mVisibleDockStates = new ArrayList<>();
74
75    public RecentsViewTouchHandler(RecentsView rv) {
76        mRv = rv;
77        mDragSlop = ViewConfiguration.get(rv.getContext()).getScaledTouchSlop();
78        updateSnapAlgorithm();
79    }
80
81    private void updateSnapAlgorithm() {
82        Rect insets = new Rect();
83        SystemServicesProxy.getInstance(mRv.getContext()).getStableInsets(insets);
84        mDividerSnapAlgorithm = DividerSnapAlgorithm.create(mRv.getContext(), insets);
85    }
86
87    /**
88     * Registers a new drop target for the current drag only.
89     */
90    public void registerDropTargetForCurrentDrag(DropTarget target) {
91        mDropTargets.add(target);
92    }
93
94    /**
95     * Returns the set of visible dock states for this current drag.
96     */
97    public ArrayList<DockState> getVisibleDockStates() {
98        return mVisibleDockStates;
99    }
100
101    /** Touch preprocessing for handling below */
102    public boolean onInterceptTouchEvent(MotionEvent ev) {
103        return handleTouchEvent(ev) || mDragRequested;
104    }
105
106    /** Handles touch events once we have intercepted them */
107    public boolean onTouchEvent(MotionEvent ev) {
108        handleTouchEvent(ev);
109        if (ev.getAction() == MotionEvent.ACTION_UP && mRv.getStack().getStackTaskCount() == 0) {
110            EventBus.getDefault().send(new HideRecentsEvent(false, true));
111        }
112        return true;
113    }
114
115    /**** Events ****/
116
117    public final void onBusEvent(DragStartEvent event) {
118        SystemServicesProxy ssp = Recents.getSystemServices();
119        mRv.getParent().requestDisallowInterceptTouchEvent(true);
120        mDragRequested = true;
121        // We defer starting the actual drag handling until the user moves past the drag slop
122        mIsDragging = false;
123        mDragTask = event.task;
124        mTaskView = event.taskView;
125        mDropTargets.clear();
126
127        int[] recentsViewLocation = new int[2];
128        mRv.getLocationInWindow(recentsViewLocation);
129        mTaskViewOffset.set(mTaskView.getLeft() - recentsViewLocation[0] + event.tlOffset.x,
130                mTaskView.getTop() - recentsViewLocation[1] + event.tlOffset.y);
131
132        // Change space coordinates relative to the view to RecentsView when user initiates a touch
133        if (event.isUserTouchInitiated) {
134            float x = mDownPos.x - mTaskViewOffset.x;
135            float y = mDownPos.y - mTaskViewOffset.y;
136            mTaskView.setTranslationX(x);
137            mTaskView.setTranslationY(y);
138        }
139
140        mVisibleDockStates.clear();
141        if (ActivityManager.supportsMultiWindow(mRv.getContext()) && !ssp.hasDockedTask()
142                && mDividerSnapAlgorithm.isSplitScreenFeasible()) {
143            Recents.logDockAttempt(mRv.getContext(), event.task.getTopComponent(),
144                    event.task.resizeMode);
145            if (!event.task.isDockable) {
146                EventBus.getDefault().send(new ShowIncompatibleAppOverlayEvent());
147            } else {
148                // Add the dock state drop targets (these take priority)
149                DockState[] dockStates = Recents.getConfiguration()
150                        .getDockStatesForCurrentOrientation();
151                for (DockState dockState : dockStates) {
152                    registerDropTargetForCurrentDrag(dockState);
153                    dockState.update(mRv.getContext());
154                    mVisibleDockStates.add(dockState);
155                }
156            }
157        }
158
159        // Request other drop targets to register themselves
160        EventBus.getDefault().send(new DragStartInitializeDropTargetsEvent(event.task,
161                event.taskView, this));
162        if (mDeviceId != -1) {
163            InputDevice device = InputDevice.getDevice(mDeviceId);
164            if (device != null) {
165                device.setPointerType(PointerIcon.TYPE_GRABBING);
166            }
167        }
168    }
169
170    public final void onBusEvent(DragEndEvent event) {
171        if (!mDragTask.isDockable) {
172            EventBus.getDefault().send(new HideIncompatibleAppOverlayEvent());
173        }
174        mDragRequested = false;
175        mDragTask = null;
176        mTaskView = null;
177        mLastDropTarget = null;
178    }
179
180    public final void onBusEvent(ConfigurationChangedEvent event) {
181        if (event.fromDisplayDensityChange || event.fromDeviceOrientationChange) {
182            updateSnapAlgorithm();
183        }
184    }
185
186    void cancelStackActionButtonClick() {
187        mRv.getStackActionButton().setPressed(false);
188    }
189
190    private boolean isWithinStackActionButton(float x, float y) {
191        Rect rect = mRv.getStackActionButtonBoundsFromStackLayout();
192        return mRv.getStackActionButton().getVisibility() == View.VISIBLE &&
193                mRv.getStackActionButton().pointInView(x - rect.left, y - rect.top, 0 /* slop */);
194    }
195
196    private void changeStackActionButtonDrawableHotspot(float x, float y) {
197        Rect rect = mRv.getStackActionButtonBoundsFromStackLayout();
198        mRv.getStackActionButton().drawableHotspotChanged(x - rect.left, y - rect.top);
199    }
200
201    /**
202     * Handles dragging touch events
203     */
204    private boolean handleTouchEvent(MotionEvent ev) {
205        int action = ev.getActionMasked();
206        boolean consumed = false;
207        float evX = ev.getX();
208        float evY = ev.getY();
209        switch (action) {
210            case MotionEvent.ACTION_DOWN:
211                mDownPos.set((int) evX, (int) evY);
212                mDeviceId = ev.getDeviceId();
213
214                if (isWithinStackActionButton(evX, evY)) {
215                    changeStackActionButtonDrawableHotspot(evX, evY);
216                    mRv.getStackActionButton().setPressed(true);
217                }
218                break;
219            case MotionEvent.ACTION_MOVE: {
220                float x = evX - mTaskViewOffset.x;
221                float y = evY - mTaskViewOffset.y;
222
223                if (mRv.getStackActionButton().isPressed() && isWithinStackActionButton(evX, evY)) {
224                    changeStackActionButtonDrawableHotspot(evX, evY);
225                }
226
227                if (mDragRequested) {
228                    if (!mIsDragging) {
229                        mIsDragging = Math.hypot(evX - mDownPos.x, evY - mDownPos.y) > mDragSlop;
230                    }
231                    if (mIsDragging) {
232                        int width = mRv.getMeasuredWidth();
233                        int height = mRv.getMeasuredHeight();
234
235                        DropTarget currentDropTarget = null;
236
237                        // Give priority to the current drop target to retain the touch handling
238                        if (mLastDropTarget != null) {
239                            if (mLastDropTarget.acceptsDrop((int) evX, (int) evY, width, height,
240                                    mRv.mSystemInsets, true /* isCurrentTarget */)) {
241                                currentDropTarget = mLastDropTarget;
242                            }
243                        }
244
245                        // Otherwise, find the next target to handle this event
246                        if (currentDropTarget == null) {
247                            for (DropTarget target : mDropTargets) {
248                                if (target.acceptsDrop((int) evX, (int) evY, width, height,
249                                        mRv.mSystemInsets, false /* isCurrentTarget */)) {
250                                    currentDropTarget = target;
251                                    break;
252                                }
253                            }
254                        }
255                        if (mLastDropTarget != currentDropTarget) {
256                            mLastDropTarget = currentDropTarget;
257                            EventBus.getDefault().send(new DragDropTargetChangedEvent(mDragTask,
258                                    currentDropTarget));
259                        }
260                    }
261                    mTaskView.setTranslationX(x);
262                    mTaskView.setTranslationY(y);
263                }
264                break;
265            }
266            case MotionEvent.ACTION_UP:
267            case MotionEvent.ACTION_CANCEL: {
268                if (mRv.getStackActionButton().isPressed() && isWithinStackActionButton(evX, evY)) {
269                    EventBus.getDefault().send(new DismissAllTaskViewsEvent());
270                    consumed = true;
271                }
272                cancelStackActionButtonClick();
273                if (mDragRequested) {
274                    boolean cancelled = action == MotionEvent.ACTION_CANCEL;
275                    if (cancelled) {
276                        EventBus.getDefault().send(new DragDropTargetChangedEvent(mDragTask, null));
277                    }
278                    EventBus.getDefault().send(new DragEndEvent(mDragTask, mTaskView,
279                            !cancelled ? mLastDropTarget : null));
280                    break;
281                }
282                mDeviceId = -1;
283            }
284        }
285        return consumed;
286    }
287}
288