媒體播放器無法在Android上通過充電器連接正確播放聲音

Question

我是軟件開發的新手，我正在嘗試制作一個可以在充電時播放聲音的應用程序。 我第一次將其連接到充電電纜時，它會播放兩次聲音，這是不期望的。 另外，當我太快地連接和斷開電纜時，它也會播放兩次。 有人知道解決這個問題的方法嗎？

package com.mccharginggimmick;

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.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.ImageView;

public class MainActivity extends AppCompatActivity {

IntentFilter intentFilter;
BroadcastReceiver broadcastReceiver;
MediaPlayer mediaPlayerOff;
MediaPlayer mediaPlayerOn;
boolean playedOnceOn;
boolean playedOnceOff;
ImageView imageView;
@Override
protected void onCreate(Bundle savedInstanceState) {

    View decorView = getWindow().getDecorView();
    int uiOptions = View.SYSTEM_UI_FLAG_FULLSCREEN;
    decorView.setSystemUiVisibility(uiOptions);

    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);



    imageView = (ImageView) findViewById(R.id.imageView);
    intentFilter = new IntentFilter(Intent.ACTION_BATTERY_CHANGED);
    broadcastReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            int status = intent.getIntExtra(BatteryManager.EXTRA_STATUS, -1);
            boolean isCharging = status == BatteryManager.BATTERY_STATUS_CHARGING || status == BatteryManager.BATTERY_STATUS_FULL;

            if(isCharging){
            onCharge();
            }
            else{
            onDisconnect();
            }
        }
    };
    MainActivity.this.registerReceiver(broadcastReceiver, intentFilter);
}
public void onCharge(){

    if(!playedOnceOn){
        imageView.setVisibility(View.INVISIBLE);
    mediaPlayerOn = MediaPlayer.create(this, R.raw.btnon);
    mediaPlayerOn.start();
    mediaPlayerOn.setOnCompletionListener(new MediaPlayer.OnCompletionListener() {
        @Override
        public void onCompletion(MediaPlayer mediaPlayer) {
            mediaPlayerOn.stop();
            playedOnceOn = true;
            playedOnceOff = false;
        }
    });
    }
}
public void onDisconnect(){

    if(!playedOnceOff){
        imageView.setVisibility(View.VISIBLE);
    mediaPlayerOff = MediaPlayer.create(this, R.raw.btnoff);
    mediaPlayerOff.start();
    mediaPlayerOff.setOnCompletionListener(new MediaPlayer.OnCompletionListener() {
        @Override
        public void onCompletion(MediaPlayer mediaPlayer) {
            mediaPlayerOff.stop();
            playedOnceOff = true;
            playedOnceOn = false;
        }
    });
    }
}
}

Answer 1

在類中定義isCabelConnected

boolean isCabelConnected = false;

然后在您的onClick

            int status = intent.getIntExtra(BatteryManager.EXTRA_STATUS, -1);
            boolean isCharging = status == BatteryManager.BATTERY_STATUS_CHARGING;
            boolean isFullCharged = status == BatteryManager.BATTERY_STATUS_FULL;

            if(isCharging && !isCabelConnected){
            onCharge();
            isCabelConnected = true;
            } else if (isFullCharged && isCabelConnected){
            onCharge();
            }
            else{
            onDisconnect();
            isCabelConnected = false;
            }

連接電纜時此代碼將發出聲音，充滿電時此代碼將發出另一聲音