android音频（1）

android音频（一）

1.通过意图使用内置的音频播放器

Intent intent=new Intent(android.content.Intent.ACTION_VIEW);File audioFile=new File(Environment.getExternalStorageDirectory()+"/Music/mylove.mp3");intent.setDataAndType(Uri.fromFile(audioFile), "audio/mp3");startActivity(intent);

2.创建自定义播放应用（在onStart中初始化MediaPlayer对象和开始播放，可以在活动不再活跃时，停止播放）

     MediaPlayer mediaPlayer；

        @Override	protected void onStart() {		// TODO Auto-generated method stub		super.onStart();		mediaPlayer = MediaPlayer.create(this, R.raw.life);		mediaPlayer.setOnCompletionListener(this);		mediaPlayer.start();	}	@Override	protected void onStop() {		// TODO Auto-generated method stub		super.onStop();		mediaPlayer.stop();		mediaPlayer.release();	}

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

完整代码如下：

package com.example.testaudioedit;import java.io.File;import android.app.Activity;import android.content.Intent;import android.media.MediaPlayer;import android.media.MediaPlayer.OnCompletionListener;import android.net.Uri;import android.os.Bundle;import android.os.Environment;import android.view.MotionEvent;import android.view.View;import android.view.View.OnClickListener;import android.view.View.OnTouchListener;import android.widget.Button;public class AudioPlayer extends Activity implements OnClickListener,		OnCompletionListener, OnTouchListener {	private MediaPlayer mediaPlayer;	private Button startButton, stopButton;	private int position = 0;// 保存播放位置	private View musicProgress;	@Override	protected void onCreate(Bundle savedInstanceState) {		super.onCreate(savedInstanceState);		setContentView(R.layout.activity_main);		initView();	}	private void initView() {		// TODO Auto-generated method stub		startButton = (Button) findViewById(R.id.internal_play);		stopButton = (Button) findViewById(R.id.internal_stop);		musicProgress = findViewById(R.id.musicView);		startButton.setOnClickListener(this);		stopButton.setOnClickListener(this);		musicProgress.setOnTouchListener(this);		mediaPlayer = MediaPlayer.create(this, R.raw.life);//资源文件，在资源文件夹下创建raw文件夹，life表示的是要播放的音频文件		mediaPlayer.setOnCompletionListener(this);		mediaPlayer.start();	}	@Override	protected void onStart() {		// TODO Auto-generated method stub		super.onStart();	}	@Override	protected void onStop() {		// TODO Auto-generated method stub		super.onStop();		mediaPlayer.stop();		mediaPlayer.release();	}	@Override	public void onClick(View v) {		// TODO Auto-generated method stub		switch (v.getId()) {		case R.id.internal_play:			if (!mediaPlayer.isPlaying())				mediaPlayer.start();			break;		case R.id.internal_stop:			if (mediaPlayer.isPlaying())				mediaPlayer.pause();			break;		default:			break;		}	}	@Override	public void onCompletion(MediaPlayer mp) {		// TODO Auto-generated method stub		mediaPlayer.start();		mediaPlayer.seekTo(position);	}	@Override	public boolean onTouch(View v, MotionEvent event) {		// TODO Auto-generated method stub		if (event.getAction() == MotionEvent.ACTION_MOVE) {			if (mediaPlayer.isPlaying()) {				position = (int) (event.getX() * mediaPlayer.getDuration() / musicProgress						.getWidth());				mediaPlayer.seekTo(position);			}		}		return true;	}}

activity_main.xml文件如下：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:id="@+id/container"    android:layout_width="match_parent"    android:layout_height="match_parent">        <Button         android:id="@+id/internal_play"        android:layout_width="150dp"        android:layout_height="60dp"        android:layout_marginLeft="10dp"        android:text="play"/>    <Button         android:id="@+id/internal_stop"        android:layout_toRightOf="@+id/internal_play"        android:layout_width="150dp"        android:layout_height="60dp"        android:text="stop"/>        <View        android:id="@+id/musicView"        android:layout_below="@+id/internal_play"        android:layout_width="fill_parent"        android:layout_height="fill_parent" />    </RelativeLayout>