1 /* 2 * Copyright (C) 2018 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.launcher3.util; 18 19 import android.os.SystemClock; 20 21 /** 22 * Determines whether a fling should be blocked. Currently we block flings when crossing thresholds 23 * to new states, and unblock after a short duration. 24 */ 25 public class FlingBlockCheck { 26 // Allow flinging to a new state after waiting this many milliseconds. 27 private static final long UNBLOCK_FLING_PAUSE_DURATION = 200; 28 29 private boolean mBlockFling; 30 private long mBlockFlingTime; 31 32 public void blockFling() { 33 mBlockFling = true; 34 mBlockFlingTime = SystemClock.uptimeMillis(); 35 } 36 37 public void unblockFling() { 38 mBlockFling = false; 39 mBlockFlingTime = 0; 40 } 41 42 public void onEvent() { 43 // We prevent flinging after passing a state, but allow it if the user pauses briefly. 44 if (SystemClock.uptimeMillis() - mBlockFlingTime >= UNBLOCK_FLING_PAUSE_DURATION) { 45 mBlockFling = false; 46 } 47 } 48 49 public boolean isBlocked() { 50 return mBlockFling; 51 } 52 } 53
