Question

我正在尝试创建一个音乐播放器（学习）。我从SD卡中检索了歌曲，其中包括歌曲的名称及其路径，该歌曲存储在ArrayList＆lt;的HashMap＆LT;字符串，字符串＆gt;＆gt;。

MainActivity.java

public class MainActivity extends AppCompatActivity {

    ListView listView;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        listView = (ListView)findViewById(R.id.listView);      

        ArrayList<HashMap<String, String>> song = new SongsManager().getPlayList();

        ArrayAdapter<HashMap<String, String>> songAdapter = new ArrayAdapter<>(getApplicationContext(), android.R.layout.simple_list_item_1, song);

        listView.setAdapter(songAdapter);

        listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {

                int itemPos = position;
                //String itemVal = (String)listView.getItemAtPosition(position);

                HashMap<String, String> m = (HashMap<String, String>) listView.getItemAtPosition(position);

                String strArr[] = new String[m.size()];
                int i = 0;

                    for (String current : m.values()) {
                        strArr[i] = current;
                        i++;
                    }


                Toast.makeText(getApplicationContext(), itemPos+" - "+strArr[1], Toast.LENGTH_SHORT).show();
            }
        });

    }

}

SongsManager.java文件

package com.example.app.musicplayer;

import android.os.Environment;

import java.io.File;
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 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);
        }
    }
}

但是当我运行应用程序时，我得到了歌曲的名称以及listView上显示的路径。

有没有办法只能显示它的名字，而不能显示它的路径。

Answer 1

创建自定义列表适配器。

public class SongListAdapter extends ArrayAdapter<SongModel> {

    Activity activity;
    int layoutResourceId;
    List<SongModel> songList = new ArrayList<SongModel>();


    public SongListAdapter(Activity activity, int layoutResourceId,
                           List<SongModel> songList
    ) {

        super(activity, layoutResourceId, songList);


        this.layoutResourceId = layoutResourceId;
        this.activity = activity;
        this.songList = songList;

    }

    @Override
    public View getView(final int position, View convertView,
                        ViewGroup parent) {

        final ViewHolder holder;
        if (convertView == null) {
            LayoutInflater inflater = ((Activity) activity)
                    .getLayoutInflater();

            convertView = inflater.inflate(layoutResourceId, parent, false);
            holder = new ViewHolder();

            holder.nameText = (TextView) convertView.findViewById(R.id.nameText);



            convertView.setTag(holder);
        } else {
            holder = (ViewHolder) convertView.getTag();
        }

        final SongModel songModel = songList.get(position);
        holder.nameText.setText(songModel.getName());


        return convertView;

    }

     static class ViewHolder {

        TextView nameText;


    }
}

如何控制setAdapter显示的内容？

1 个答案: