Question

我有一个小部件，当它创建时应该启动广播接收器。更换电池后，此接收器会处理小部件更新。

这是我的代码：

AppWidgetProvider代码：

public void onUpdate(Context context, AppWidgetManager appWidgetManager, int[] appWidgetIds) {
broadcastReceiver = new BatteryInfo();
IntentFilter mIntentFilter = new IntentFilter();
mIntentFilter.addAction(Intent.ACTION_BATTERY_CHANGED);
context.getApplicationContext().registerReceiver(broadcastReceiver, mIntentFilter);
}

BroadcastReceiver代码

public class BatteryInfo extends BroadcastReceiver {
    public void onReceive(Context context, Intent intent) {
    // some actions...
    }
}

添加小部件后，此方法可以正常工作。 Widget的onUpdate会被调用，然后当电池状态发生变化时，接收方会继续被调用。

重启设备后问题开始。设备重新启动后，几秒钟后小部件重新初始化，再次调用小部件的onUpdate，然后两次调用接收器，并立即死亡。之后，它会出现在logcat中：

1950-3391/? I/ActivityManager: Process [my process name] (pid 7752) has died: cch+4CEM 
1950-2013/? W/BroadcastQueue: Background execution not allowed: receiving Intent { act=android.intent.action.ACTION_POWER_DISCONNECTED flg=0x4000010 (has extras) } to [my process name]/.BatteryInfo
1950-2013/? W/BroadcastQueue: Background execution not allowed: receiving Intent { act=android.intent.action.ACTION_POWER_CONNECTED flg=0x4000010 (has extras) } to [my process name]/.BatteryInfo

为什么在重新启动后重新初始化窗口小部件有什么关系？只要窗口小部件在屏幕上，我如何确保我的接收器保持活动状态？

Answer 1

您忘了Unregister BroadCastReceiver吗？请检查您的Unregistered是否broadcastReciever比您更合适。

Answer 2

这是预期的。

对设备进行重新设置后，所有侦听器都将被删除，您应该重新注册它们。在这种情况下，您需要收听BOOT_COMPLETE事件以重新注册您的广播。像这样：

AndroidManifest.xml：

<manifest>
    ...
    <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />
    ...
    <application>
        ...
        <!-- UPDATE YOUR BatteryInfo RECEIVER WITH the INFO BELOW -->
        <receiver
            ...
            android:permission="android.permission.RECEIVE_BOOT_COMPLETED"
            android:exported="true">
            <intent-filter>
                ...
                <action android:name="android.intent.action.BOOT_COMPLETED" />
            </intent-filter>
        </receiver>
    </application>
</manifest>

BatteryInfo.java

public class BatteryInfo extends BroadcastReceiver {
    public void onReceive(Context context, Intent intent) {
        String action = intent.getAction();
        if("android.intent.action.BOOT_COMPLETED".equals(action) {
            Log.v("BatteryInfo", "Boot completed. Registering to battery info events");
            IntentFilter intentFilter = new IntentFilter(Intent.ACTION_BATTERY_CHANGED);
            context.getApplicationContext().registerReceiver(this, intentFilter);
        } else if() {
            Log.v("BatteryInfo", "Battery event");
            // Some Actions
        } else {
            Log.e("BatteryInfo", "Action not expected: " + action);
        }
    }
}

重新启动设备后注册，BroadcastReceiver将被杀死

2 个答案: