Android實戰 - 第三十五話 音樂播放

已經好幾天不更新博客了，今天輕松一點模擬個簡單的“音樂播放器”。1分鐘看完~

整個簡單布局，加幾個控制按鈕：

 

主活動代碼也是soeasy：

 

 

package com.example.playaudiotest;

import java.io.File;

import android.app.Activity;
import android.media.MediaPlayer;
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 {

	private Button play;

	private Button pause;

	private Button stop;

	private MediaPlayer mediaPlayer = new MediaPlayer();

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		play = (Button) findViewById(R.id.play);
		pause = (Button) findViewById(R.id.pause);
		stop = (Button) findViewById(R.id.stop);
		play.setOnClickListener(this);
		pause.setOnClickListener(this);
		stop.setOnClickListener(this);
		initMediaPlayer();
	}

	private void initMediaPlayer() {
		try {
			File file = new File(Environment.getExternalStorageDirectory(), "music.mp3");
			//設置播放路徑，資源
			mediaPlayer.setDataSource(file.getPath());
			//播放前的准備工作
			mediaPlayer.prepare();
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	@Override
	public void onClick(View v) {
		switch (v.getId()) {
		case R.id.play:
			if (!mediaPlayer.isPlaying()) {
				//開始播放
				mediaPlayer.start();
			}
			break;
		case R.id.pause:
			if (mediaPlayer.isPlaying()) {
				//暫停播放
				mediaPlayer.pause();
			}
			break;
		case R.id.stop:
			if (mediaPlayer.isPlaying()) {
				//Resets the MediaPlayer to its uninitialized state. After calling this method, you will have to initialize it again by setting the data source and calling prepare(). 
				//重置，如果調用此方法，必須人為的再次調用設置資源、准備方法
				mediaPlayer.reset();
				initMediaPlayer();
			}
			break;
		default:
			break;
		}
	}

	@Override
	protected void onDestroy() {
		super.onDestroy();
		if (mediaPlayer != null) {
			mediaPlayer.stop();
			mediaPlayer.release();
		}
	}

}

需要重點關注的是mediaPlayer.reset();方法。看文檔說明：

 

Resets the MediaPlayer to its uninitialized state. After calling this method, you will have to initialize it again by setting the data source and calling prepare().
大致意思是：重置，如果調用此方法，必須人為的再次調用設置資源、准備方法

既然調用了就在此調用initMediaPlayer();

運行，開始聽音樂吧~~