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public class PowerUtil {
public static boolean isConnected(Context context) {
Intent intent = context.registerReceiver(null, new IntentFilter(Intent.ACTION_BATTERY_CHANGED));
int plugged = intent.getIntExtra(BatteryManager.EXTRA_PLUGGED, -1);
return plugged == BatteryManager.BATTERY_PLUGGED_AC || plugged == BatteryManager.BATTERY_PLUGGED_USB;
}
}