使用service实现一个简单的音乐播放器

效果

布局文件

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              android:orientation="horizontal"
              android:layout_width="fill_parent"
              android:layout_height="fill_parent"
              android:gravity="center_horizontal"
        >

    <Button
            android:id="@+id/stop"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="停止"
            android:onClick="stopOnClick"
            />
    <Button
            android:id="@+id/play"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="播放"
            android:onClick="playOnClick"

            />
    <Button
            android:id="@+id/pause"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="暂停"
            android:onClick="pauseOnClick"

            />
</LinearLayout>

service子类书写

package com.startservicedemo;

import android.app.Service;
import android.content.Intent;
import android.media.MediaPlayer;
import android.os.IBinder;

/**
 * Created by IntelliJ IDEA
 * Project: com.startservicedemo
 * Author: 安诺爱成长
 * Email: 1399487511@qq.com
 * Date: 2015/5/13
 */
public class PlayService extends Service {

    private MediaPlayer player;

    @Override
    public void onCreate() {
        super.onCreate();
        player = MediaPlayer.create(this, R.raw.ai);
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        int control = intent.getIntExtra("control", -1);
        switch (control) {
            case 0:
                player.start();
                break;
            case 1:
                player.stop();
                break;
            case 2:
                player.pause();
                break;
        }
        return super.onStartCommand(intent, flags, startId);
    }

    @Override
    public IBinder onBind(Intent intent) {
        return null;
    }

    @Override
    public void onDestroy() {
        player.stop();
        player.release();
        player = null;
        super.onDestroy();
    }
}

activity书写

package com.startservicedemo;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

public class MainActivity extends Activity {
    /**
     * Called when the activity is first created.
     */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        Button stopButton = (Button) findViewById(R.id.stop);
        Button playButton = (Button) findViewById(R.id.play);
        Button pauseButton = (Button) findViewById(R.id.pause);
        //启动服务
        Intent intent = new Intent(this, PlayService.class);
        startService(intent);
    }

    @Override
    protected void onStop() {
        //停止startservice启动的服务
        Intent intent = new Intent(this, PlayService.class);
        stopService(intent);
        super.onStop();
    }

    //停止播放监听方法
    public void stopOnClick(View view) {
        Intent intent = new Intent(this, PlayService.class);
        intent.putExtra("control", 1);
        startService(intent);
    }

    //暂停播放监听方法
    public void pauseOnClick(View view) {
        Intent intent = new Intent(this, PlayService.class);
        intent.putExtra("control", 2);
        startService(intent);
    }

    //停止播放监听方法
    public void playOnClick(View view) {
        Intent intent = new Intent(this, PlayService.class);
        intent.putExtra("control", 0);
        startService(intent);
    }
}