仅使用广播接收机显示吐司一次

Question

请注意： 我正在backgroundService中运行整个代码。

[我想要的是每当我将手机断开/连接到USB或AC适配器时，都会显示一条敬酒消息。

我的问题是，吐司消息会自动重复。 BroadcastReceiver提供更新时，该方法会不断执行，并且吐司一遍又一遍地出现。

没有连接电缆时，将重复“已卸下充电”的吐司消息。当连接了交流适配器或USB充电器时，相应的消息。

import android.app.Notification;
import android.app.Service;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.media.MediaPlayer;
import android.os.BatteryManager;
import android.os.Binder;
import android.os.IBinder;
import android.util.Log;
import android.widget.Toast;

import androidx.core.app.NotificationCompat;

import static com.hashware.batteryalert.App.channelID;

public class MyService extends Service {

    private static final String TAG = MyService.class.getSimpleName();
    public int level, voltage, status, plugged;

    private final IBinder iBinder = new bindingService();
    private MediaPlayer player;

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {

        IntentFilter intF = new IntentFilter();
        intF.addAction(Intent.ACTION_BATTERY_CHANGED);

        registerReceiver(br,intF);
        Log.d(TAG, "onStartCommand: ServiceStarted");

        return START_STICKY;
    }

    //    TODO: Fetching live battery data

    BroadcastReceiver br = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            level = intent.getIntExtra(BatteryManager.EXTRA_LEVEL,0);
            voltage = intent.getIntExtra(BatteryManager.EXTRA_VOLTAGE,0);
            status = intent.getIntExtra(BatteryManager.EXTRA_STATUS,0);
            plugged = intent.getIntExtra(BatteryManager.EXTRA_PLUGGED,0);

            switch (plugged){
                case BatteryManager.BATTERY_PLUGGED_AC:
                    notificationCreate();
                    Toast.makeText(MyService.this,"Charging : AC Supply", Toast.LENGTH_SHORT).show();
                    break;

                case BatteryManager.BATTERY_PLUGGED_USB:
                    notificationCreate();
                    Toast.makeText(MyService.this,"Charging : USB Supply", Toast.LENGTH_SHORT).show();
                    break;

                case BatteryManager.BATTERY_PLUGGED_WIRELESS:
                    notificationCreate();
                    Toast.makeText(MyService.this,"Charging : Wireless Supply", Toast.LENGTH_SHORT).show();
                    break;

                case 0:
                    stopForeground(true);
                    break;
            }

    //            TODO: Notify Battery Status

            if (status == BatteryManager.BATTERY_STATUS_FULL) {
                if (player == null) {
                    player = MediaPlayer.create(MyService.this, R.raw.electric_shock01);
                    player.start();
                    player.setLooping(true);
                }
            } else if (status == BatteryManager.BATTERY_STATUS_DISCHARGING){
                if (player != null) {
                    player.release();
                    player = null;
                    Toast.makeText(MyService.this, "Disconnected After Full charge !", Toast.LENGTH_SHORT).show();
                }
            else if (player == null){
                Toast.makeText(MyService.this, "Charging Removed !", Toast.LENGTH_SHORT).show();
                Log.d(TAG, "onReceive: BLANK");
            }
        }
    }
};

Answer 1

[如果只需要检测手机何时与USB /适配器连接或断开连接，则可能应该监视充电状态的变化，而不是ACTION_BATTERY_CHANGED。请参考此https://developer.android.com/training/monitoring-device-state/battery-monitoring#MonitorChargeState