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我有一個運行線程的服務。該線程將一些數據保存在文件中（在SD卡中）。當Android進入睡眠狀態時，我需要服務和線程繼續運行。我用PARTIAL_WAKE_LOCK嘗試了它，但它不起作用;線程停止，而Android正在睡覺。像FULL_WAKE_LOCK之類的其他鎖定工作，但我需要使用PARTIAL_WAKE_LOCK，因爲將來，在該線程中，我將從串行端口讀取數據，而不關心屏幕關閉。PARTIAL_WAKE_LOCK和線程在服務中運行
我不知道我是否在代碼中出現了一些錯誤，或者我不明白PARTIAL_WAKE_LOCK。有人可以告訴我爲什麼我的解決方案無法解決？
這是主要活動的代碼，其中的服務stareted的一部分：
public void onClick(View v) {
if (SerialPortService.WAKELOCK == null) {
PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE);
SerialPortService.WAKELOCK = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, SerialPortService.WL_TAG);
SerialPortService.WAKELOCK.acquire();
startService(new Intent(getApplicationContext(), SerialPortService.class));
}
}
這是服務的代碼：
public class SerialPortService extends Service {
public static String WL_TAG = "serial_port_wl_tag";
public static PowerManager.WakeLock WAKELOCK = null;
private BufferedWriter out = null;
private ReadThread readThread;
public IBinder onBind(Intent intent) {
return null;
}
public void onCreate() {
super.onCreate();
try {
File root = Environment.getExternalStorageDirectory();
if (root.canWrite()){
File dataFile = new File(root, "batterytest.txt");
FileWriter dataFileWritter = new FileWriter(dataFile);
out = new BufferedWriter(dataFileWritter);
}
} catch (IOException ioe) {
Log.d("TEST", "Could not open file " + ioe.getMessage());
}
readThread = new ReadThread();
readThread.start();
}
public void onDestroy() {
if (readThread != null) readThread.interrupt();
WAKELOCK.release();
WAKELOCK = null;
try {
out.close();
} catch (IOException ioe) {
Log.d("TEST", "Could not close file " + ioe.getMessage());
}
super.onDestroy();
}
private class ReadThread extends Thread {
public void run() {
super.run();
while (!isInterrupted()) {
try {
Thread.sleep(5000);
if (out != null) {
Calendar now = Calendar.getInstance();
out.write(now.getTime().toString());
out.newLine();
} catch (IOException ioe) {
Log.d("TEST", "Could not read file " + ioe.getMessage());}
return;
} catch (InterruptedException e) {
return;
}
}
}
}
}