Question

我想在listview中显示来自sdcard的歌曲，但它会给出Force Close。任何人都可以帮助我。代码：

package com.ex.imageGallery;

import java.io.File;

import android.app.Activity;
import android.content.Intent;
import android.graphics.drawable.ColorDrawable;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ArrayAdapter;
import android.widget.ImageView;
import android.widget.ListView;
import java.io.FilenameFilter;

public class audioList extends Activity{


 @Override
    public void onCreate(Bundle savedInstanceState) {
     Uri[] mUrls;
    String[] mFiles=null; 
        super.onCreate(savedInstanceState);

        setContentView(R.layout.audio_list);
        ListView lv;
        lv = (ListView)findViewById(R.id.LV);
        /*File home = Environment.getDataDirectory();
        File[] audioList = home.listFiles(new FilenameFilter() {

            public boolean accept(File dir, String name) {
                // TODO Auto-generated method stub
                return(name.endsWith(".mp3"));
            }
        });
        mFiles = new String[audioList.length];
        for(int i=0;i<audioList.length;i++)
        {
            mFiles[i] = audioList[i].getAbsolutePath();
        }
        mUrls = new Uri[mFiles.length];
        for(int i=0;i<mFiles.length;i++)
        {
            mUrls[i] = Uri.parse(mFiles[i]);
        }
        lv.setAdapter(new ArrayAdapter<String>(audioList.this,R.layout.new_list,mFiles));
        lv.setDividerHeight(2);
        lv.setTextFilterEnabled(true); */
 }
 }

Answer 1

系统会自动注册媒体文件，因此您需要使用查询来检索媒体。

final Cursor cursor = managedQuery(MediaStore.Audio.Media.EXTERNAL_CONTENT_URI, 
     new String[] { MediaStore.Audio.Media.DISPLAY_NAME }, null, null, null);

加载光标。要在ListView中显示它，您需要使用SimpleCursorAdapter在ListView中显示数据。

Answer 2

public class Database extends Activity {
    /** Called when the activity is first created. */
    private List<String> list;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        //creating a folder in sdcard
        File file = new File(Environment.getExternalStorageDirectory()
                + File.separator
                + "mymusic" //folder name
           );

        if(!file.exists()) {
            file.mkdirs();
        }

        ListView lv=(ListView) findViewById(R.id.listView1);
        list=getSD(); 

        lv.setAdapter((ListAdapter) new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, list));

    }

    //read from sdcard
    private List<String> getSD() {
        List<String> item = new ArrayList<String>();
        File f = new File("/mnt/sdcard/mymusic");
        File[] files = f.listFiles();

        for(int i=0; i < files.length; i++) {
            File file = files[i];
            //take the file name only
            String myfile = file.getPath().substring(file.getPath().lastIndexOf("/")+1,file.getPath().length()).toLowerCase(); 
            item.add(myfile);
        }

        return item;
    }

播放SDCARD的歌曲

2 个答案: