| /* |
| * Copyright (C) 2022 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.systemui.classifier; |
| |
| import android.view.MotionEvent; |
| |
| import java.util.List; |
| |
| /** |
| * Falsing classifier that accepts or rejects a gesture as a tap. |
| */ |
| public abstract class TapClassifier extends FalsingClassifier{ |
| private final float mTouchSlop; |
| |
| TapClassifier(FalsingDataProvider dataProvider, |
| float touchSlop) { |
| super(dataProvider); |
| mTouchSlop = touchSlop; |
| } |
| |
| @Override |
| Result calculateFalsingResult( |
| @Classifier.InteractionType int interactionType, |
| double historyBelief, double historyConfidence) { |
| return isTap(getRecentMotionEvents(), 0.5); |
| } |
| |
| /** Given a list of {@link android.view.MotionEvent}'s, returns true if the look like a tap. */ |
| public Result isTap(List<MotionEvent> motionEvents, double falsePenalty) { |
| if (motionEvents.isEmpty()) { |
| return falsed(0, "no motion events"); |
| } |
| float downX = motionEvents.get(0).getX(); |
| float downY = motionEvents.get(0).getY(); |
| |
| for (MotionEvent event : motionEvents) { |
| String reason; |
| if (Math.abs(event.getX() - downX) >= mTouchSlop) { |
| reason = "dX too big for a tap: " |
| + Math.abs(event.getX() - downX) |
| + "vs " |
| + mTouchSlop; |
| return falsed(falsePenalty, reason); |
| } else if (Math.abs(event.getY() - downY) >= mTouchSlop) { |
| reason = "dY too big for a tap: " |
| + Math.abs(event.getY() - downY) |
| + " vs " |
| + mTouchSlop; |
| return falsed(falsePenalty, reason); |
| } |
| } |
| return Result.passed(0); |
| } |
| } |