1 /* 2 * Copyright (C) 2010 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; 18 19 import android.os.Handler; 20 import android.os.SystemClock; 21 22 public class Alarm implements Runnable{ 23 // if we reach this time and the alarm hasn't been cancelled, call the listener 24 private long mAlarmTriggerTime; 25 26 // if we've scheduled a call to run() (ie called mHandler.postDelayed), this variable is true. 27 // We use this to avoid having multiple pending callbacks 28 private boolean mWaitingForCallback; 29 30 private Handler mHandler; 31 private OnAlarmListener mAlarmListener; 32 private boolean mAlarmPending = false; 33 Alarm()34 public Alarm() { 35 mHandler = new Handler(); 36 } 37 setOnAlarmListener(OnAlarmListener alarmListener)38 public void setOnAlarmListener(OnAlarmListener alarmListener) { 39 mAlarmListener = alarmListener; 40 } 41 42 // Sets the alarm to go off in a certain number of milliseconds. If the alarm is already set, 43 // it's overwritten and only the new alarm setting is used setAlarm(long millisecondsInFuture)44 public void setAlarm(long millisecondsInFuture) { 45 long currentTime = SystemClock.uptimeMillis(); 46 mAlarmPending = true; 47 long oldTriggerTime = mAlarmTriggerTime; 48 mAlarmTriggerTime = currentTime + millisecondsInFuture; 49 50 // If the previous alarm was set for a longer duration, cancel it. 51 if (mWaitingForCallback && oldTriggerTime > mAlarmTriggerTime) { 52 mHandler.removeCallbacks(this); 53 mWaitingForCallback = false; 54 } 55 if (!mWaitingForCallback) { 56 mHandler.postDelayed(this, mAlarmTriggerTime - currentTime); 57 mWaitingForCallback = true; 58 } 59 } 60 cancelAlarm()61 public void cancelAlarm() { 62 mAlarmPending = false; 63 } 64 65 // this is called when our timer runs out run()66 public void run() { 67 mWaitingForCallback = false; 68 if (mAlarmPending) { 69 long currentTime = SystemClock.uptimeMillis(); 70 if (mAlarmTriggerTime > currentTime) { 71 // We still need to wait some time to trigger spring loaded mode-- 72 // post a new callback 73 mHandler.postDelayed(this, Math.max(0, mAlarmTriggerTime - currentTime)); 74 mWaitingForCallback = true; 75 } else { 76 mAlarmPending = false; 77 if (mAlarmListener != null) { 78 mAlarmListener.onAlarm(this); 79 } 80 } 81 } 82 } 83 alarmPending()84 public boolean alarmPending() { 85 return mAlarmPending; 86 } 87 } 88