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1 package org.hedgewars.hedgeroid.util; |
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2 |
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3 import android.os.Handler; |
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4 import android.os.Looper; |
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5 import android.os.Message; |
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6 |
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7 /** |
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8 * This class handles regularly calling a specified runnable |
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9 * on the looper provided in the constructor. The first call |
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10 * occurs without delay (though still via the looper), all |
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11 * following calls are delayed by (approximately) the interval. |
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12 * The interval can be changed at any time, which will cause |
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13 * an immediate execution of the runnable again. |
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14 */ |
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15 public class TickHandler extends Handler { |
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16 private final Runnable callback; |
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17 private int messageId; |
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18 private long interval; |
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19 private boolean running; |
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20 |
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21 public TickHandler(Looper looper, long interval, Runnable callback) { |
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22 super(looper); |
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23 this.callback = callback; |
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24 this.interval = interval; |
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25 } |
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26 |
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27 public synchronized void stop() { |
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28 messageId++; |
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29 running = false; |
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30 } |
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31 |
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32 public synchronized void start() { |
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33 messageId++; |
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34 sendMessage(obtainMessage(messageId)); |
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35 running = true; |
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36 } |
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37 |
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38 public synchronized void setInterval(long interval) { |
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39 this.interval = interval; |
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40 if(running) { |
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41 start(); |
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42 } |
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43 } |
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44 |
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45 @Override |
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46 public synchronized void handleMessage(Message msg) { |
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47 if(msg.what == messageId) { |
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48 callback.run(); |
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49 } |
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50 if(msg.what == messageId) { |
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51 sendMessageDelayed(obtainMessage(messageId), interval); |
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52 } |
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53 } |
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54 } |