andorid Activity和Service音乐播放器

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.hanqi.testservice">

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MusicPlay2">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <activity android:name=".MusicPlay1">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

        <service
            android:name=".TestService1"
            android:enabled="true"
            android:exported="true" />
        <service
            android:name=".MusicService"
            android:enabled="true"
            android:exported="true"></service>
    </application>

</manifest>

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.hanqi.blacklist.MusicPlay1"
    android:orientation="vertical">

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="播放状态:"
        android:id="@+id/tv_1"/>
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content">
        <Button
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="播放"
            android:onClick="play_onclick"/>
        <Button
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="暂停"
            android:onClick="pause_onclick"/>
        <Button
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="停止"
            android:onClick="stop_onclick"/>
        <Button
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="退出"
            android:onClick="exit_onclick"/>
    </LinearLayout>

</LinearLayout>

package com.hanqi.testservice;

import android.media.MediaPlayer;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.TextView;

public class MusicPlay1 extends AppCompatActivity {
    TextView tv1;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_music_play1);

        tv1 = (TextView)findViewById(R.id.tv_1);
        tv1.setText("播放状态：停止");
    }
    //媒体播放器的类
    private MediaPlayer mediaPlayer;
    public void play_onclick(View v)
    {
        if (mediaPlayer == null) {
            //调用MediaPlayer的静态方法create()
            mediaPlayer = MediaPlayer.create(this, R.raw.shinain);
        }
        mediaPlayer.start();

        tv1.setText("播放状态：正在播放");
    }
    public void stop_onclick(View v)
    {
        if (mediaPlayer != null)
        {
            mediaPlayer.stop();//停止
            mediaPlayer.reset();//重置
            mediaPlayer.release();//释放
            mediaPlayer = null;
        }
        tv1.setText("播放状态：停止");
    }
    public void pause_onclick(View v)
    {
        if (mediaPlayer != null&& mediaPlayer.isPlaying())
        {
            mediaPlayer.pause();
            tv1.setText("播放状态：暂停");
        }

    }
    public void exit_onclick(View v)
    {
        stop_onclick(v);
        //退出
        finish();

    }

}

package com.hanqi.testservice;

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

public class MusicService extends Service {
    public MusicService() {
    }

    @Override
    public IBinder onBind(Intent intent) {
        // TODO: Return the communication channel to the service.
        throw new UnsupportedOperationException("Not yet implemented");
    }

    private MediaPlayer mediaPlayer;
    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        //获取意图传递的信息
        String action = intent.getStringExtra("action");
        switch (action)
        {
            case "play":
                if (mediaPlayer == null)
                {
                    mediaPlayer = MediaPlayer.create(this,R.raw.shinain);
                }
                mediaPlayer.start();
                break;
            case "stop":
                if (mediaPlayer != null)
                {
                    mediaPlayer.stop();
                    mediaPlayer.reset();
                    mediaPlayer.release();
                    mediaPlayer = null;
                }
                break;
            case "pause":
                if (mediaPlayer != null && mediaPlayer.isPlaying()) {
                    mediaPlayer.pause();
                }
                break;
        }

        return super.onStartCommand(intent, flags, startId);
    }
}

package com.hanqi.testservice;

import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.TextView;

public class MusicPlay2 extends AppCompatActivity {
    TextView tv1;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_music_play1);

        tv1 = (TextView)findViewById(R.id.tv_1);
        tv1.setText("播放状态1：停止");
    }

    public void play_onclick(View v)
    {
        Intent intent = new Intent(this,MusicService.class);
        intent.putExtra("action", "play");
        startService(intent);
        tv1.setText("播放状态1：正在播放...");
    }
    public void stop_onclick(View v)
    {
        Intent intent = new Intent(this,MusicService.class);
        intent.putExtra("action","stop");
        startService(intent);
        tv1.setText("播放状态1：停止");
    }
    public void pause_onclick(View v)
    {
        Intent intent = new Intent(this,MusicService.class);
        intent.putExtra("action","pause");
        startService(intent);
            tv1.setText("播放状态1：暂停");
    }
    public void exit_onclick(View v)
    {
        stop_onclick(v);
        //退出
        finish();

    }

}