1 /*
2  * Hedgewars for Android. An Android port of Hedgewars, a free turn based strategy game
3  * Copyright (C) 2012 Simeon Maxein <smaxein@googlemail.com>
4  *
5  * This program is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU General Public License
7  * as published by the Free Software Foundation; either version 2
8  * of the License, or (at your option) any later version.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
18  */
19 
20 package org.hedgewars.hedgeroid.util;
21 
22 import android.os.Handler;
23 import android.os.Looper;
24 import android.os.Message;
25 
26 /**
27  * This class handles regularly calling a specified runnable
28  * on the looper provided in the constructor. The first call
29  * occurs without delay (though still via the looper), all
30  * following calls are delayed by (approximately) the interval.
31  * The interval can be changed at any time, which will cause
32  * an immediate execution of the runnable again.
33  */
34 public class TickHandler extends Handler {
35     private final Runnable callback;
36     private int messageId;
37     private long interval;
38     private boolean running;
39 
TickHandler(Looper looper, long interval, Runnable callback)40     public TickHandler(Looper looper, long interval, Runnable callback) {
41         super(looper);
42         this.callback = callback;
43         this.interval = interval;
44     }
45 
stop()46     public synchronized void stop() {
47         messageId++;
48         running = false;
49     }
50 
start()51     public synchronized void start() {
52         messageId++;
53         sendMessage(obtainMessage(messageId));
54         running = true;
55     }
56 
setInterval(long interval)57     public synchronized void setInterval(long interval) {
58         this.interval = interval;
59         if(running) {
60             start();
61         }
62     }
63 
64     @Override
handleMessage(Message msg)65     public synchronized void handleMessage(Message msg) {
66         if(msg.what == messageId) {
67             callback.run();
68         }
69         if(msg.what == messageId) {
70             sendMessageDelayed(obtainMessage(messageId), interval);
71         }
72     }
73 }