Android学习笔记之Service

与服务通信

用bindservice

而startservice并无通信条件.

service 为android为系统服务，所以程序员无法new出来，只能建立服务，共其他组件使用。

package com.jiahemeikang.helloandroid;

import com.jiahemikang.service.EchoService;

import com.jiahemikang.service.EchoService.EchoServiceBingder;

import android.os.Bundle;

import android.os.IBinder;

import android.app.Activity;

import android.content.ComponentName;

import android.content.Context;

import android.content.Intent;

import android.content.ServiceConnection;

import android.view.Menu;

import android.view.View;

import android.view.View.OnClickListener;

import android.widget.Button;

import android.widget.TextView;

public class MainActivity extends Activity implements OnClickListener,ServiceConnection{

    private TextView tvResult ;

    private Intent serviceIntent;

    private Button btnStarAty1;

    private Button btnStarService;

    private Button btnStopService;

    private Button btnBingService;

    private Button btnUnBingService;

    private Button btnGetNum;

    public EchoService echoService = null;

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        serviceIntent = new Intent(this,EchoService.class);

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

        tvResult = (TextView)findViewById(R.id.tvResult);

        btnStarAty1= (Button)findViewById(R.id.btnStartAty1);

        btnStarService= (Button)findViewById(R.id.btnStartService);

        btnStopService= (Button)findViewById(R.id.btnStopService);

        btnStarService.setOnClickListener(this);

        btnStopService.setOnClickListener(this);

        btnBingService= (Button)findViewById(R.id.bingdingservice);

        btnUnBingService= (Button)findViewById(R.id.unbingdingservice);

        btnBingService.setOnClickListener(this);

        btnUnBingService.setOnClickListener(this);

        btnGetNum= (Button)findViewById(R.id.btnGetNum);

        btnGetNum.setOnClickListener(this);

        btnStarAty1.setOnClickListener(new View.OnClickListener(){

            @Override

            public void onClick(View v){

                Intent i = new Intent(MainActivity.this,Aty1.class);

                i.putExtra("txt","Hello aty1");

                startActivity(i);

                startActivityForResult(i,0);

            }

        });

    }

    @Override

    protected void onActivityResult(int a,int b ,Intent i){

        if (i!=null) {

            String result = i.getStringExtra("result");

            tvResult.setText(result);

        }

    }

    @Override

    public boolean onCreateOptionsMenu(Menu menu) {

        // Inflate the menu; this adds items to the action bar if it is present.

        getMenuInflater().inflate(R.menu.main, menu);

        return true;

    }

    @Override

    public void onClick(View v) {

        // TODO Auto-generated method stub

        switch (v.getId()) {

        case R.id.btnStartService:

            startService(serviceIntent);

            break;

        case R.id.btnStopService:

            stopService(serviceIntent);

            break;

        case R.id.bingdingservice:

            bindService(serviceIntent,this,Context.BIND_AUTO_CREATE);

            break;

        case R.id.unbingdingservice:

            unbindService(this);

            echoService =null;

            break;

        case R.id.btnGetNum:

            if (echoService!=null) {

                System.out.print("当前服务的 数字为"+echoService.getCountNum());

            }

            break;

        default:

            break;

        }

    }

    @Override

    public void onServiceConnected(ComponentName arg0, IBinder binder) {

        System.out.println("onServiceConnected");

        echoService = ((EchoService.EchoServiceBingder)binder).getService();

    }

    @Override

    public void onServiceDisconnected(ComponentName arg0) {

        // TODO Auto-generated method stub

    }

    //onStart

}

服务代码

package com.jiahemikang.service;

import java.util.Timer;

import java.util.TimerTask;

import android.app.Service;

import android.content.Intent;

import android.os.Binder;

import android.os.IBinder;

public class EchoService extends Service {

    public EchoService() {

    }

    @Override

    public IBinder onBind(Intent arg0) {

        System.out.println("onBind");

        return echoServiceBingder;

    }

    private Timer timer = null;

    private TimerTask task = null;

    public void startTimer(){

        if(timer ==null){

            timer = new Timer();

            task = new TimerTask(){

                @Override

                public void run() {

                    // TODO Auto-generated method stub

                    i++;

                    System.out.println("-"+i+"-");

                }};

                timer.schedule(task,1000,1000);

        }

    }

    private int i =0;

    public void StopTimer(){

        if (timer!=null) {

            timer.cancel();

            task.cancel();

            timer =null;

            task =null;

        }

    }

    public int getCountNum(){

        return i;

    }

    private final EchoServiceBingder echoServiceBingder = new EchoServiceBingder();

    public class EchoServiceBingder extends Binder{

        public EchoService getService(){

            return EchoService.this;

        }

    }

    @Override

    public void onCreate(){

        System.out.println("onCreate");

        startTimer();

        super.onCreate();

    }

    @Override

    public void onDestroy(){

        System.out.println("onDestroy");

        StopTimer();

        super.onDestroy();

    }

}