1 /* 2 * Copyright (C) 2024 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 17 package com.android.wm.shell.back 18 19 import android.view.MotionEvent 20 import android.view.VelocityTracker 21 22 internal class ProgressVelocityTracker { 23 private val velocityTracker: VelocityTracker = VelocityTracker.obtain() 24 private var downTime = -1L 25 addPositionnull26 fun addPosition(timeMillis: Long, position: Float) { 27 if (downTime == -1L) downTime = timeMillis 28 velocityTracker.addMovement( 29 MotionEvent.obtain( 30 /* downTime */ downTime, 31 /* eventTime */ timeMillis, 32 /* action */ MotionEvent.ACTION_MOVE, 33 /* x */ position, 34 /* y */ 0f, 35 /* metaState */0 36 ) 37 ) 38 } 39 40 /** calculates current velocity (unit: progress per second) */ calculateVelocitynull41 fun calculateVelocity(): Float { 42 velocityTracker.computeCurrentVelocity(1000) 43 return velocityTracker.xVelocity 44 } 45 resetTrackingnull46 fun resetTracking() { 47 velocityTracker.clear() 48 downTime = -1L 49 } 50 }