扣丁学堂笔记第22天多媒体播放

1.简单介绍与播放三种媒体源

MainActivity

package com.example.mediaplayertest;

import java.io.IOException;

import android.app.Activity;
import android.media.MediaPlayer;
import android.media.MediaPlayer.OnPreparedListener;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;

public class MainActivity extends Activity {

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

	public void playResClick(View view) {

		// MediaPlayer mp = MediaPlayer.create(this, R.raw.a1);
		// mp.start();
	}

	public void playSysClick(View view) {

		MediaPlayer mp = new MediaPlayer();
		String path = Environment
				.getExternalStoragePublicDirectory(Environment.DIRECTORY_MUSIC)
				+ "/a2.mp3";
		try {
			mp.setDataSource(this, Uri.parse(path));
			mp.prepare();// 同步运行
			mp.start();
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}

	public void playNetClick(View view) {

		// 音乐链接要保证有效
		String path = "http://y.qq.com/index.html#type=song&mid=0040E7kG0ZJ9al&tpl=yqq_song_detail";
		MediaPlayer mp = new MediaPlayer();
		try {
			mp.setDataSource(this, Uri.parse(path));
			mp.setOnPreparedListener(new OnPreparedListener() {

				@Override
				public void onPrepared(MediaPlayer mp) {
					// TODO Auto-generated method stub
					mp.start();
				}
			});
			mp.prepareAsync();
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
}

activtiy_main

<RelativeLayout 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.example.mediaplayertest.MainActivity" >

    <Button
        android:id="@+id/button1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_alignParentRight="true"
        android:layout_alignParentTop="true"
        android:text="播放本地文件"
        android:onClick="playResClick" />

    <Button
        android:id="@+id/button2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_alignRight="@+id/button1"
        android:layout_below="@+id/button1"
        android:text="播放系统文件" 
        android:onClick="playSysClick"/>

    <Button
        android:id="@+id/button3"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignLeft="@+id/button2"
        android:layout_alignRight="@+id/button2"
        android:layout_below="@+id/button2"
        android:text="播放网络文件"
        android:onClick="playNetClick" />

</RelativeLayout>

AndroidManifest

<uses-permission android:name="android.permission.INTERNET"/>

2.MediaPlayer状态分析

3.简单的播放器实现案例

MainActivity

package com.example.simpleplayertest;

import java.io.File;
import java.io.IOException;
import java.util.ArrayList;

import android.app.Activity;
import android.media.MediaPlayer;
import android.media.MediaPlayer.OnCompletionListener;
import android.media.MediaPlayer.OnErrorListener;
import android.media.MediaPlayer.OnPreparedListener;
import android.os.Bundle;
import android.os.Environment;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;

public class MainActivity extends Activity implements OnClickListener,
		OnPreparedListener, OnErrorListener, OnCompletionListener {

	private MediaPlayer player;
	private int index = 0;//表示当前要播放的音乐的索引
	private ArrayList<String> musicList = new ArrayList<String>();
	private Button btn_play, btn_pause, btn_last, btn_next;
	private boolean isPause = false;//true表示暂停状态
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);

		initView();
		initMusic();
		player = new MediaPlayer();
		player.setOnPreparedListener(this);
		player.setOnErrorListener(this);
		player.setOnCompletionListener(this);

	}

	private void initView() {
		// TODO Auto-generated method stub
		btn_play = (Button) findViewById(R.id.btn_play);
		btn_pause = (Button) findViewById(R.id.btn_pause);
		btn_last = (Button) findViewById(R.id.btn_last);
		btn_next = (Button) findViewById(R.id.btn_next);

		btn_play.setOnClickListener(this);
		btn_pause.setOnClickListener(this);
		btn_last.setOnClickListener(this);
		btn_next.setOnClickListener(this);
	}

	private void initMusic() {
		String root = Environment.getExternalStoragePublicDirectory(
				Environment.DIRECTORY_MUSIC).getPath();

		musicList.add(root + File.separator + "a.mp3");
		musicList.add(root + File.separator + "b.mp3");
		musicList.add(root + File.separator + "c.mp3");
		musicList.add(root + File.separator + "d.mp3");
	}

	@Override
	protected void onDestroy() {
		// TODO Auto-generated method stub
		super.onDestroy();
		if(player!=null){
			if(player.isPlaying()){
				player.stop();
			}
			player.release();
		}
	}
	
	@Override
	public void onCompletion(MediaPlayer mp) {
		// TODO Auto-generated method stub
		next();
	}

	@Override
	public boolean onError(MediaPlayer mp, int what, int extra) {
		// TODO Auto-generated method stub
		player.reset();
		return true;
	}

	@Override
	public void onPrepared(MediaPlayer mp) {
		// TODO Auto-generated method stub
		mp.start();
	}

	@Override
	public void onClick(View v) {
		// TODO Auto-generated method stub
		switch (v.getId()) {
		case R.id.btn_play:
			play();
			break;
		case R.id.btn_pause:
			pause();
			break;
		case R.id.btn_last:
			last();
			break;
		case R.id.btn_next:
			next();
			break;
		default:
			break;
		}
	}

	private void next() {
		// TODO Auto-generated method stub
		if(index+1<musicList.size()-1){
			index++;
		}else{
			index = 0;
		}
		start();
	}

	private void last() {
		// TODO Auto-generated method stub
		if(index-1>=0){
			index--;
		}else{
			index = musicList.size()-1;
		}
		start();
	}

	//暂停
	private void pause() {
		// TODO Auto-generated method stub
		if(player.isPlaying()){
			player.pause();
			isPause = true;
		}
	}

	private void play() {
		// TODO Auto-generated method stub
		if(isPause){
			player.start();//接着播放（不是从头開始）
			isPause = false;
		}else{
			start();//音乐从头開始播放的方法
		}
	}

	//音乐从头開始播放的方法
	private void start() {
		// TODO Auto-generated method stub
		if(index<musicList.size()){
			if(player.isPlaying()){
				player.stop();
			}
			player.reset();
			String musicPath = musicList.get(index);
			try {
				player.setDataSource(musicPath);
				player.prepareAsync();//之后调用onPrepared方法
				isPause = false;
			}catch (IOException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		}
	}
}

activity_main

<RelativeLayout 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.example.simpleplayertest.MainActivity" >

    <ImageView
        android:id="@+id/imageView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:layout_centerVertical="true"
        android:src="@drawable/ic_launcher" />

    <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@+id/imageView1"
        android:orientation="horizontal" >

        <Button
            android:id="@+id/btn_last"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="上一首"
            android:layout_weight="1" />

        <Button
            android:id="@+id/btn_play"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignBottom="@+id/button1"
            android:layout_toRightOf="@+id/button1"
            android:text="播放" 
            android:layout_weight="1"/>

        <Button
            android:id="@+id/btn_pause"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignBaseline="@+id/button2"
            android:layout_alignBottom="@+id/button2"
            android:layout_toRightOf="@+id/button2"
            android:text="暂停" 
            android:layout_weight="1"/>

        <Button
            android:id="@+id/btn_next"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignBaseline="@+id/button3"
            android:layout_alignBottom="@+id/button3"
            android:layout_alignParentRight="true"
            android:text="下一首" 
            android:layout_weight="1"/>
    </LinearLayout>
   
</RelativeLayout>

4.在服务中使用MediaPlayer

5.作为前台服务执行

在服务中使用mediaplayer+作为前台服务执行代码

MyService.java

package com.example.servicemediaplayertest;

import java.io.File;
import java.io.IOException;

import android.app.Notification;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.app.Service;
import android.app.Notification.Builder;
import android.content.Context;
import android.content.Intent;
import android.media.MediaPlayer;
import android.media.MediaPlayer.OnPreparedListener;
import android.net.wifi.WifiManager;
import android.os.Environment;
import android.os.IBinder;
import android.os.PowerManager;

public class MyService extends Service implements OnPreparedListener{

	public static final String ACTION_PLAY = "com.example.servicemediaplayertest.ACTION_PLAY";
	public static final String ACTION_PAUSE = "com.example.servicemediaplayertest.ACTION_PAUSE";
	public static final String ACTION_EXIT = "com.example.servicemediaplayertest.ACTION_EXIT";
	private MediaPlayer player;
	private WifiManager.WifiLock lock;
	@Override
	public void onCreate() {
		// TODO Auto-generated method stub
		super.onCreate();
		player = new MediaPlayer();
		//保持cpu正常工作
		player.setWakeMode(getApplicationContext(), PowerManager.PARTIAL_WAKE_LOCK);
		//保持wifi不被休眠
		WifiManager wifiManager = (WifiManager) getSystemService(Context.WIFI_SERVICE);
		lock = wifiManager.createWifiLock("myLock");
		lock.acquire();
		player.setOnPreparedListener(this);
		notification();
	}
	
	private void notification() {
		// TODO Auto-generated method stub
		Notification.Builder builder = new Builder(this);
		builder.setTicker("为她音悦");
		builder.setSmallIcon(R.drawable.ic_launcher);
		builder.setContentTitle("我的音乐播放器");
		builder.setContentInfo("正在播放");
		PendingIntent pi = PendingIntent.getActivity(this, 0, new Intent(this,MainActivity.class), PendingIntent.FLAG_UPDATE_CURRENT);
		builder.setContentIntent(pi);
		NotificationManager nm = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
		Notification notification = builder.build();
		startForeground(0, notification);
		nm.notify(0,notification);
	}

	@Override
	public int onStartCommand(Intent intent, int flags, int startId) {
		// TODO Auto-generated method stub
		String action = intent.getAction();
		if(ACTION_PLAY.equals(action)){
			player.reset();
			try {
				player.setDataSource(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_MUSIC)+File.separator+"a.mp3");
				player.prepareAsync();
			}catch (IOException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		}else if(ACTION_PAUSE.equals(action)){
			if(player.isPlaying())player.pause();
		}else if(ACTION_EXIT.equals(action)){
			if(player.isPlaying())player.stop();
			player.release();
		}
		return super.onStartCommand(intent, flags, startId);
	}
	
	@Override
	public void onDestroy() {
		// TODO Auto-generated method stub
		super.onDestroy();
		stopForeground(true);
		lock.release();
	}
	
	@Override
	public IBinder onBind(Intent intent) {
		// TODO Auto-generated method stub
		return null;
	}

	@Override
	public void onPrepared(MediaPlayer mp) {
		// TODO Auto-generated method stub
		mp.start();
	}

}

MainActivity

package com.example.servicemediaplayertest;

import android.app.Activity;
import android.app.Notification;
import android.app.Notification.Builder;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.view.KeyEvent;
import android.view.View;

public class MainActivity extends Activity {

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

//	@Override
//	public boolean onKeyDown(int keyCode, KeyEvent event) {
//		// TODO Auto-generated method stub
//		if(keyCode==KeyEvent.KEYCODE_BACK){
//			
//		}
//		return super.onKeyDown(keyCode, event);
//	}
	
	public void playClick(View view) {

		Intent intent = new Intent(MyService.ACTION_PLAY);
		startService(intent);
	}

	public void pauseClick(View view) {

		Intent intent = new Intent(MyService.ACTION_PAUSE);
		startService(intent);
	}

	public void exitClick(View view) {

		Intent intent = new Intent(MyService.ACTION_EXIT);
		startService(intent);
	}
}

activity_main

<RelativeLayout 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.example.servicemediaplayertest.MainActivity" >

    <Button
        android:id="@+id/button1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_alignParentTop="true"
        android:text="PLAY" 
        android:onClick="playClick"/>

    <Button
        android:id="@+id/button2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignLeft="@+id/button1"
        android:layout_below="@+id/button1"
        android:text="PAUSE" 
        android:onClick="pauseClick"/>

    <Button
        android:id="@+id/button3"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignLeft="@+id/button2"
        android:layout_below="@+id/button2"
        android:text="EXIT" 
        android:onClick="exitClick"/>

</RelativeLayout>

Androidmanifest

 <uses-permission android:name="android.permission.WAKE_LOCK"/>

<service android:name=".MyService"
            android:process=":music">
            <intent-filter>
                <action android:name="com.example.servicemediaplayertest.ACTION_PLAY"/>
                <action android:name="com.example.servicemediaplayertest.ACTION_PAUSE"/>
                <action android:name="com.example.servicemediaplayertest.ACTION_EXIT"/>
            </intent-filter>
            </service>

6.处理音频焦点

7.ContentResolver获取媒体信息

8.ContentResolver測试