android - 如何保持应用程序在后台运行？

Question

我正在制作一个短信阅读器应用程序。一旦他们在广播监听器的帮助下收到传入的消息我的 Activity 收到消息，并在文本到语音类的帮助下读取消息。问题是一旦他们收到消息，我的 Activity 就会出现在前台。任何人都可以帮助我如何让我的应用程序仅在后台运行吗？我正在粘贴我的代码以供引用。谢谢 !

MyBroadcastReceiver. java
package com.example.sms_reader;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.telephony.SmsMessage;
import android.util.Log;


public class MyBrodcastReceiver extends BroadcastReceiver{

    @Override
    public void onReceive(Context arg0, Intent intent) 
    {
        Log.d("tag1", "Receiver is activated");
        Log.d("tag2", "msg");
        Bundle bundle = intent.getExtras(); 

        if (bundle != null)
        {   
            Object[] pdus = (Object[]) bundle.get("pdus");
            SmsMessage[] messages = new SmsMessage[pdus.length]; 
            for (int i = 0; i < pdus.length; i++) 
            {
        messages[i] = SmsMessage.createFromPdu((byte[]) pdus[i]); 
            }
        for (SmsMessage message : messages) 
            {
                String msg = message.getMessageBody();
                long when = message.getTimestampMillis();  
                String from = message.getOriginatingAddress();  
                Log.d("tag2", msg);
                Log.d("tag3", from);
                Intent i = new Intent(arg0 ,Texttospeech.class);
                i.putExtra("msg", msg);
                i.putExtra("when", when);
                i.putExtra("from", from);
                i.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                arg0.startActivity(i); 
                Log.d("tag4", "intent called");

            }


        }
        else{
            Log.d("tag2", "bundle not received");
        }
    }

}


Texttospeech.java
package com.example.sms_reader;

import java.util.Locale;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.speech.tts.TextToSpeech;
import android.util.Log;

public class Texttospeech extends Activity implements
TextToSpeech.OnInitListener
{

TextToSpeech tts ; 
String content;

protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    Log.d("tag4", "INTENT RECEIVED");
    tts = new TextToSpeech(this, this);    
    Intent data = getIntent();
    Log.d("tag5", "INTENT ");
    String msg = data.getStringExtra("msg");
    String from = data.getStringExtra("from");
    content = "You have received a message from" +from +"and it says"+msg;
    Log.d("tag6", content);
    speakOut(); 

};

private void speakOut() {


    tts.speak(content, TextToSpeech.QUEUE_FLUSH, null);
}   

@Override
public void onDestroy() {
    // Don't forget to shutdown!
    if (tts != null) {
        tts.stop();
        tts.shutdown();
    }
    super.onDestroy();
}

@Override
public void onInit(int status) {
    // TODO Auto-generated method stub

    if (status == TextToSpeech.SUCCESS) {

        int result = tts.setLanguage(Locale.US);

        // tts.setPitch(5); // set pitch level

        // tts.setSpeechRate(2); // set speech speed rate

        if (result == TextToSpeech.LANG_MISSING_DATA
                || result == TextToSpeech.LANG_NOT_SUPPORTED) {
            Log.e("TTS", "Language is not supported");
        } 
        else {

            speakOut();
        }

                                         } 
    else 
    {
        Log.e("TTS", "Initilization Failed");
    }

}
}

Answer 1

您正在调用文本到语音 Activity ，这就是它每次弹出的原因。如果您想将其保留在后台，请将您的文字转语音 Activity 更改为服务。