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我已经写了一个android程序,其中包含按下音量按钮时增加1的计数器。当按下此按钮时,它也应该关闭屏幕,并在重新打开之前等待5秒钟不活动。但是当我运行应用程序时,除了计数器增加之外没有任何事情发生,即屏幕没有关闭。按下音量按钮时关闭屏幕
这里是我的java类:
public class MainActivity extends Activity {
private TextView counterTextView;
int count;
PowerManager.WakeLock wakeLock;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
counterTextView = (TextView) findViewById(R.id.counterTextView);
}
@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
// TODO Auto-generated method stub
if (keyCode == KeyEvent.KEYCODE_VOLUME_UP && event.getRepeatCount() == 0) {
count++;
counterTextView.setText(" " + count + " ");
PowerManager powerManager = (PowerManager) getSystemService(POWER_SERVICE);
wakeLock = powerManager.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK,
"MyWakelockTag");
wakeLock.acquire();
new Handler().postDelayed(screenOnRunnable(), 5000);
return true;
}
return super.onKeyDown(keyCode, event);
}
private Runnable screenOnRunnable() {
return new Runnable() {
@Override
public void run() {
wakeLock.release();
}
};
}
}
我还添加了WAKE_LOCK权限在清单:
<uses-permission android:name="android.permission.WAKE_LOCK" />
我不知道什么是错的...任何帮助将不胜感激。
您没有传递上下文,也没有在创建访问POWER_SERVICE时使用。 – Ali786 2015-04-04 11:35:27