Question

我的代码有问题，我无法在第二次尝试中跟踪问题，player.setDataSource(afd.getFileDescriptor(), afd.getStartOffset(), afd.getLength());无法在第一次尝试捕获语句中确定AssetFileDescriptor ..

它表示局部变量未初始化..但如果我将其初始化为null ..

该应用程序将不幸关闭..

package com.thesis.americansignlanguage;

import java.io.IOException;

import android.app.Activity;
import android.content.res.AssetFileDescriptor;
import android.media.MediaPlayer;
import android.os.Bundle;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.widget.TextView;
import android.widget.VideoView;

public class Videocompareclass extends Activity {
String get;
VideoView gesture;
int charIndex;
char[] getArray;


@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);
    setContentView(R.layout.gesturecompare);
    SurfaceView videoView = (SurfaceView)findViewById(R.id.sf_view);
    SurfaceHolder holder = videoView.getHolder();
    Bundle gotWord = getIntent().getExtras();
    get = gotWord.getString("key");
    TextView Word = (TextView)findViewById(R.id.textView1);
    Word.setText(get);

    AssetFileDescriptor afd;
    try {
        afd = getAssets().openFd("hello.mp4");
    } catch(IOException e1) {
        e1.printStackTrace();
    }

    MediaPlayer player = new MediaPlayer();

    if(player.isPlaying()) {
        player.reset();
    }

    player.setDisplay(holder);

    try {
        player.setDataSource(afd.getFileDescriptor(), afd.getStartOffset(), afd.getLength());
        player.prepare();
    }
    catch(IllegalArgumentException e) {
        e.printStackTrace();
    }
    catch(IllegalStateException e) {
        e.printStackTrace();
    }
    catch(IOException e) {
        e.printStackTrace();
    }
    player.start();

  }
}

Answer 1

AssetFileDescriptor afd;
try {
    afd = getAssets().openFd("hello.mp4");
} catch(IOException e1) {
    e1.printStackTrace();
}
//...
try {
    player.setDataSource(afd.getFileDescriptor(), afd.getStartOffset(), afd.getLength());
    player.prepare();
}

如果存在异常，则afd变量在第二次尝试/捕获时可能尚未初始化。

您可以将两个try / catch块合并为一个：

try {
    AssetFileDescriptor afd = getAssets().openFd("hello.mp4");
    MediaPlayer player = new MediaPlayer();
    if(player.isPlaying()) {
        player.reset();
    }
    player.setDisplay(holder);
    player.setDataSource(afd.getFileDescriptor(), afd.getStartOffset(), afd.getLength());
    player.prepare();
    player.start();
}
catch(IllegalArgumentException e) {
    e.printStackTrace();
}
catch(IllegalStateException e) {
    e.printStackTrace();
}
catch(IOException e) {
    e.printStackTrace();
}

Answer 2

请检查问题http://www.pressinganswer.com/1821030/android-media-player-error-1-4-while-playing-an-audio-from-assets-folder

在准备播放器之前必须关闭资产文件描述符。这就是我解决问题的方法：

player = new MediaPlayer(); AssetFileDescriptor afd =
BeeDailyConvo.this.getAssets().openFd("sounds/"+file);
player.setDataSource(afd.getFileDescriptor(),afd.getStartOffset(),afd.getLength());
afd.close();**//just added this line**
player.prepare();
player.start();

似乎是解决方案

Android如何从assets文件夹播放媒体文件（.mp4）

2 个答案: