android第十八步音乐播放器

音乐播放器使用Android自带SDK实现

主要功能包括：播放、暂停、重播、停止、电话来时暂停通话结束后继续的功能

MediaPlayer：用于播放多媒体文件

方法：release()是否资源

 　　  isPlaying()是否正在播放

        getCurrentPosition()获取播放位置，返回值为int型

     　reset()把各项参数恢复到初始状态

　　  setDataSource(path)设置要播放的文件path路径

　　  prepare()进行缓冲

　　  start()开始播放

　　  pause()暂停

 　　 seekTo(0)跳转到哪，0为从头开始播放

　　  stop()停止播放

事件：setOnPreparedListener缓存完毕触发

TelephonyManager获取手机信息

listen根据状态监听手机，如果是监听的状体就触发事件

package com.example.musicplay;

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

import android.media.MediaPlayer;
import android.media.MediaPlayer.OnPreparedListener;
import android.os.Bundle;
import android.os.Environment;
import android.app.Activity;
import android.content.Context;
import android.telephony.PhoneStateListener;
import android.telephony.TelephonyManager;
import android.view.Menu;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class MainActivity extends Activity {

    EditText editText;
    String path;
    MediaPlayer mediaPlayer;
    boolean pause;
    int position;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        editText = (EditText)this.findViewById(R.id.filename);
        mediaPlayer = new MediaPlayer();
        TelephonyManager telephonyManager = (TelephonyManager)getSystemService(Context.TELEPHONY_SERVICE);
        telephonyManager.listen(new MyPhoneListener(), PhoneStateListener.LISTEN_CALL_STATE);
        
    }
    private final class MyPhoneListener extends PhoneStateListener{
        @Override
        public void onCallStateChanged(int state, String incomingNumber) {
        switch(state){
        case TelephonyManager.CALL_STATE_RINGING:
            if(mediaPlayer.isPlaying()){
                position=mediaPlayer.getCurrentPosition();
                mediaPlayer.stop();
            }
            break;
        case TelephonyManager.CALL_STATE_IDLE:
            if(position >0 && path!=null){
                play(position);
            }
            break;
        }
        }
    }
    @Override
    protected void onDestroy() {
        mediaPlayer.release();
        mediaPlayer = null;
        super.onDestroy();
    }
    public void play(View view){
        String filename = editText.getText().toString();
        switch (view.getId()) {
        case R.id.play:
            File audio = new File("/data/data/com.example.musicplay/1.mp3");
            if(audio.exists()){
                path=audio.getAbsolutePath();
                play(0);
            }
            else{
                Toast.makeText(getApplicationContext(),path+ " "+ R.string.filenoexist, Toast.LENGTH_LONG).show();
            }
            break;
        case R.id.pause:
            if(mediaPlayer.isPlaying()){
                mediaPlayer.pause();
                pause=true;
                ((Button)view).setText(R.string.continues);
            }
            else{
                if(pause){
                    mediaPlayer.start();
                    pause=false;
                    ((Button)view).setText(R.string.pausebutton);
                }
            }
            break;
        case R.id.reset:
            if(mediaPlayer.isPlaying()){
                mediaPlayer.seekTo(0);
            }
            else{
                if(path!=null){
                    play(0);
                }
            }
            break;
        case R.id.stop:
            if(mediaPlayer.isPlaying()){
                mediaPlayer.stop();
            }
            break;
        default:
            break;
        }
        
        
    }
    /*
    @Override
    protected void onPause() {
        if(mediaPlayer.isPlaying()){
            position=mediaPlayer.getCurrentPosition();
            mediaPlayer.stop();
        }
        super.onPause();
    }
    @Override
    protected void onResume() {
        if(position >0 && path!=null){
            play();
            mediaPlayer.seekTo(position);
        }
        super.onResume();
    }*/
    private void play(int p){
        
        try {
            mediaPlayer.reset(); //把各项参数恢复到初始状态
            mediaPlayer.setDataSource(path);
            mediaPlayer.prepare();//进行缓冲
            mediaPlayer.setOnPreparedListener(new PrepareListener(p));
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        
    }
    private final class PrepareListener implements OnPreparedListener{
        int pos;
        public PrepareListener(int p) {
            pos = p;
            // TODO Auto-generated constructor stub
        }

        @Override
        public void onPrepared(MediaPlayer arg0) {
            mediaPlayer.start();
            if(pos>0){
                mediaPlayer.seekTo(pos);
            }
        }
        
    }
    @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;
    }

}