| /* |
| * Copyright (C) 2021 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.server.accessibility.magnification; |
| |
| import android.annotation.NonNull; |
| import android.content.Context; |
| import android.os.Handler; |
| import android.util.MathUtils; |
| import android.view.MotionEvent; |
| import android.view.ViewConfiguration; |
| |
| import com.android.server.accessibility.gestures.GestureMatcher; |
| |
| /** |
| * This class is responsible for detecting that the user is using two fingers to perform |
| * swiping gestures or just stay pressed on the screen. The gesture matching result is determined |
| * in a duration. |
| */ |
| final class TwoFingersDownOrSwipe extends GestureMatcher { |
| |
| private final int mDoubleTapTimeout; |
| private final int mDetectionDurationMillis; |
| private final int mSwipeMinDistance; |
| private MotionEvent mFirstPointerDown; |
| private MotionEvent mSecondPointerDown; |
| |
| TwoFingersDownOrSwipe(Context context) { |
| super(MagnificationGestureMatcher.GESTURE_TWO_FINGERS_DOWN_OR_SWIPE, |
| new Handler(context.getMainLooper()), null); |
| mDetectionDurationMillis = MagnificationGestureMatcher.getMagnificationMultiTapTimeout( |
| context); |
| mDoubleTapTimeout = ViewConfiguration.getDoubleTapTimeout(); |
| mSwipeMinDistance = ViewConfiguration.get(context).getScaledTouchSlop(); |
| |
| } |
| |
| @Override |
| protected void onDown(MotionEvent event, MotionEvent rawEvent, int policyFlags) { |
| mFirstPointerDown = MotionEvent.obtain(event); |
| cancelAfter(mDetectionDurationMillis, event, rawEvent, policyFlags); |
| } |
| |
| @Override |
| protected void onPointerDown(MotionEvent event, MotionEvent rawEvent, int policyFlags) { |
| if (mFirstPointerDown == null) { |
| cancelGesture(event, rawEvent, policyFlags); |
| } |
| if (event.getPointerCount() == 2) { |
| mSecondPointerDown = MotionEvent.obtain(event); |
| completeAfter(mDoubleTapTimeout, event, rawEvent, policyFlags); |
| } else { |
| cancelGesture(event, rawEvent, policyFlags); |
| } |
| } |
| |
| @Override |
| protected void onMove(MotionEvent event, MotionEvent rawEvent, int policyFlags) { |
| if (mFirstPointerDown == null || mSecondPointerDown == null) { |
| return; |
| } |
| if (distance(mFirstPointerDown, /* move */ event) > mSwipeMinDistance) { |
| completeGesture(event, rawEvent, policyFlags); |
| return; |
| } |
| if (distance(mSecondPointerDown, /* move */ event) > mSwipeMinDistance) { |
| // The second pointer is swiping. |
| completeGesture(event, rawEvent, policyFlags); |
| } |
| } |
| |
| @Override |
| protected void onPointerUp(MotionEvent event, MotionEvent rawEvent, int policyFlags) { |
| cancelGesture(event, rawEvent, policyFlags); |
| } |
| |
| @Override |
| protected void onUp(MotionEvent event, MotionEvent rawEvent, int policyFlags) { |
| cancelGesture(event, rawEvent, policyFlags); |
| } |
| |
| @Override |
| public void clear() { |
| if (mFirstPointerDown != null) { |
| mFirstPointerDown.recycle(); |
| mFirstPointerDown = null; |
| } |
| if (mSecondPointerDown != null) { |
| mSecondPointerDown.recycle(); |
| mSecondPointerDown = null; |
| } |
| super.clear(); |
| } |
| |
| @Override |
| protected String getGestureName() { |
| return this.getClass().getSimpleName(); |
| } |
| |
| private static double distance(@NonNull MotionEvent downEvent, @NonNull MotionEvent moveEvent) { |
| final int downActionIndex = downEvent.getActionIndex(); |
| final int downPointerId = downEvent.getPointerId(downActionIndex); |
| final int moveActionIndex = moveEvent.findPointerIndex(downPointerId); |
| if (moveActionIndex < 0) { |
| return -1; |
| } |
| return MathUtils.dist(downEvent.getX(downActionIndex), downEvent.getY(downActionIndex), |
| moveEvent.getX(moveActionIndex), moveEvent.getY(moveActionIndex)); |
| } |
| } |