当用户按下电源按钮（--> 屏幕关闭）时，我正在尝试保存当前的电池电量。
起初，我有一个广播接收器，它会在手机启动时启动。它的任务是启动一项服务，该服务为屏幕关闭/开启意图创建另一个广播接收器（ - 由于在清单中指定屏幕关闭意图时它不起作用，我通过此服务动态创建它）
我的启动接收器
public class MyStartupReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context c, Intent i) {
if(i.getAction().equals(Intent.ACTION_BOOT_COMPLETED))
{
Log.d("Boot completed", "Boot completed");
c.startService(new Intent(c, CreateReceiverService.class));
}
}
}
创建接收器服务
public class CreateReceiverService extends Service {
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
// TODO Auto-generated method stub
IntentFilter filter = new IntentFilter(Intent.ACTION_SCREEN_OFF);
filter.addAction(Intent.ACTION_USER_PRESENT);
filter.addAction(Intent.ACTION_BATTERY_CHANGED);
BroadcastReceiver mReceiver = new ScreenReceiver();
registerReceiver(mReceiver, filter);
Log.d("Service", "Receiver registered");
return super.onStartCommand(intent, flags, startId);
}
这是 ScreenReceiver
public class ScreenReceiver extends BroadcastReceiver {
private int lastBatteryLevel;
@Override
public void onReceive(Context c, Intent i) {
if(i.getAction().equals(Intent.ACTION_USER_PRESENT))
{
Log.d("Screen unlock", "Screen unlock");
}
else if(i.getAction().equals(Intent.ACTION_SCREEN_OFF))
{
Log.d("Screen off", "Screen off");
Intent s = new Intent(c, ActionService.class);
s.putExtra("LVL", lastBatteryLevel);
c.startService(s);
}
else if(i.getAction().equals(Intent.ACTION_BATTERY_CHANGED))
{
lastBatteryLevel = i.getIntExtra(BatteryManager.EXTRA_LEVEL, -1);
Log.d("Battery changed", "level = "+lastBatteryLevel);
}
}
现在我的问题：ActionService 应该将电池电量保存到首选项文件： ActionService
public class ActionService extends Service {
private SharedPreferences p = PreferenceManager.getDefaultSharedPreferences(this);
Editor e = p.edit();
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
// TODO Auto-generated method stub
e.putInt("LOCKLVL", intent.getIntExtra("LVL", -1));
e.commit();
Log.d("Saved preference", "saved "+p.getInt("LOCKLVL", -1));
return super.onStartCommand(intent, flags, startId);
}
问题是当收到屏幕关闭意图时没有任何反应 - 我的 ActionService 应该保存电池电量，但没有被调用。
我的 Logcat 输出是：
Receiver registered
Screen off
并且ActionService 的 Log.d("Saved preference", "saved "+p.getInt("LOCKLVL", -1));没有输出
我什至尝试设置这样的唤醒锁： ScreenReceiver
else if(i.getAction().equals(Intent.ACTION_SCREEN_OFF))
{
WakelockHelper.acquireCpuWakeLock(c); //WAKELOCK TRY
Log.d("Screen off", "Screen off"); //OUTPUT OK
Intent s = new Intent(c, ActionService.class);
s.putExtra("LVL", lastBatteryLevel);
c.startService(s); //NOT CALLED
}
并在保存首选项后释放它。但这并没有改变任何东西。
为了完整起见，这是我的WakelockHelper课程
public class WakelockHelper {
private static PowerManager.WakeLock sCpuWakeLock;
static void acquireCpuWakeLock(Context context) {
if (sCpuWakeLock != null) {
return;
}
PowerManager pm = (PowerManager) context.getSystemService(Context.POWER_SERVICE);
sCpuWakeLock = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK,"Tag");
sCpuWakeLock.acquire();
Log.i("Wakelock", "Wakelock set");
}
static void releaseCpuLock() {
if (sCpuWakeLock != null) {
sCpuWakeLock.release();
sCpuWakeLock = null;
Log.i("Wakelock", "Wakelock released");
}
}
}
那么，当用户锁定手机时，如何保存当前的电池电量呢？为什么屏幕关闭意图后我的服务没有启动？为什么唤醒锁没有任何改变？
谢谢！