如何在Android中从内部和外部SD卡播放mp3文件？

Question

I am working on a mp3 player app, which plays .mp3 files present anywhere inside an internal SD card.

I have used the following codes to fetch the .mp3 files present in internal storage.

ArrayList<File> inFiles = new ArrayList<File>();
File list[] = file.listFiles();
//Log.i("DIR", "PATH" +file.getPath());
for (int i = 0; i < list.length; i++) 
{
    // myList.add( list[i].getName() );
    File temp_file = new File(file.getAbsolutePath(),list[i].getName());
    //Log.i("DIR", "PATH" +temp_file.getAbsolutePath());
    if (temp_file.listFiles() != null) 
    {
        //Log.i("inside", "call fn");
        listfiles(temp_file);

    }
    else 
    {
        if (list[i].getName().toLowerCase().contains(".mp3"))
        {
            inFiles.add(list[i]);
        //Log.e("Music", list[i].getName());
        }
    }
}

How do I similarly get the .mp3 files from external SD card as well?

Answer 1

You can get the root directory of the external sdcard using this code of line

File root = Environment.getExternalStorageDirectory();

Now you can do the same thing as you do for internal

ArrayList<File> inFiles = new ArrayList<File>();
File list[] = root.listFiles(); // here use the root object of File class to the list of files and directory from the external storage
//Log.i("DIR", "PATH" +file.getPath());
for (int i = 0; i < list.length; i++) 
{
    // myList.add( list[i].getName() );
    File temp_file = new File(file.getAbsolutePath(),list[i].getName());
    //Log.i("DIR", "PATH" +temp_file.getAbsolutePath());
    if (temp_file.listFiles() != null) 
    {
        //Log.i("inside", "call fn");
        listfiles(temp_file);

    }
    else 
    {
        if (list[i].getName().toLowerCase().contains(".mp3"))
        {
            inFiles.add(list[i]);
        //Log.e("Music", list[i].getName());
        }
    }
}

Answer 2

Trying using this:

File root = Environment.getExternalStorageDirectory();

That will get you the root of the external storage, provided that there is one. Then you can filter out files that aren't .mp3

Also consider looking at this: List all of one file type on Android device?

Answer 3

要获得对位于sdcard / music / song.mp3上的文件的引用，请执行以下操作：

File file = Environment.getExternalStorageDirectory()+"/music/song.mp3";

Answer 4

import java.io.File;
import java.io.FilenameFilter;
import java.util.ArrayList;
import java.util.HashMap;

    enter code here

import android.os.Environment;

public class SongsManager {


    final String MEDIA_PATH = Environment.getExternalStorageDirectory()``
            .getPath() + "/";
    private ArrayList<HashMap<String, String>> songsList = new ArrayList<HashMap<String, String>>();
    private String mp3Pattern = ".mp3";
    // Constructor
    public SongsManager(){

    }

    /**
     * Function to read all mp3 files from sdcard
     * and store the details in ArrayList
     * */
    public ArrayList<HashMap<String, String>> getPlayList(){
         System.out.println(MEDIA_PATH);
            if (MEDIA_PATH != null) {
                File home = new File(MEDIA_PATH);
                File[] listFiles = home.listFiles();
                if (listFiles != null && listFiles.length > 0) {
                    for (File file : listFiles) {
                        System.out.println(file.getAbsolutePath());
                        if (file.isDirectory()) {
                            scanDirectory(file);
                        } else {
                            addSongToList(file);
                        }
                    }
                }
            }
            // return songs list array
            return songsList;
        }

        private void scanDirectory(File directory) {
            if (directory != null) {
                File[] listFiles = directory.listFiles();
                if (listFiles != null && listFiles.length > 0) {
                    for (File file : listFiles) {
                        if (file.isDirectory()) {
                            scanDirectory(file);
                        } else {
                            addSongToList(file);
                        }

                    }
                }
            }
        }

        private void addSongToList(File song) {
            if (song.getName().endsWith(mp3Pattern)) {
                HashMap<String, String> songMap = new HashMap<String, String>();
                songMap.put("songTitle",
                        song.getName().substring(0, (song.getName().length() - 4)));
                songMap.put("songPath", song.getPath());

                // Adding each song to SongList
                songsList.add(songMap);
            }
        }
    /**
     * Class to filter files which are having .mp3 extension
     * */
    class FileExtensionFilter implements FilenameFilter {
        public boolean accept(File dir, String name) {
            return (name.endsWith(".mp3") || name.endsWith(".MP3"));
        }
    }
}

Answer 5

A slight Modification to Tushar Gupta's Codes. This worked fine for me. I have complete code for a Music Player

import android.os.Environment;
import java.io.File;
import java.io.FilenameFilter;
import java.util.ArrayList;
import java.util.HashMap;
public class SongsManager {


        final String MEDIA_PATH = Environment.getExternalStorageDirectory().getPath() + "/";
        private ArrayList<HashMap<String, String>> songsList = new ArrayList<HashMap<String, String>>();
        private String mp3Pattern = ".mp3";
        // Constructor
        public SongsManager(){

        }

        /**
         * Function to read all mp3 files from sdcard
         * and store the details in ArrayList
         * */
        public ArrayList<HashMap<String, String>> getPlayList(){
            System.out.println(MEDIA_PATH);
            if (MEDIA_PATH != null) {
                File home = new File(MEDIA_PATH);
                File[] listFiles = home.listFiles();
                if (listFiles != null && listFiles.length > 0) {
                    for (File file : listFiles) {
                        System.out.println(file.getAbsolutePath());
                        if (file.isDirectory()) {
                            scanDirectory(file);
                        } else {
                            addSongToList(file);
                        }
                    }
                }
            }
            // return songs list array
            return songsList;
        }

        private void scanDirectory(File directory) {
            if (directory != null) {
                File[] listFiles = directory.listFiles();
                if (listFiles != null && listFiles.length > 0) {
                    for (File file : listFiles) {
                        if (file.isDirectory()) {
                            scanDirectory(file);
                        } else {
                            addSongToList(file);
                        }

                    }
                }
            }
        }

        private void addSongToList(File song) {
            if (song.getName().endsWith(mp3Pattern)) {
                HashMap<String, String> songMap = new HashMap<String, String>();
                songMap.put("songTitle",
                        song.getName().substring(0, (song.getName().length() - 4)));
                songMap.put("songPath", song.getPath());

                // Adding each song to SongList
                songsList.add(songMap);
            }
        }
        /**
         * Class to filter files which are having .mp3 extension
         * */
        class FileExtensionFilter implements FilenameFilter {
            public boolean accept(File dir, String name) {
                return (name.endsWith(".mp3") || name.endsWith(".MP3"));
            }
        }
    }