我创建MP3播放器。我成功地从我的设备获取歌曲的名称和艺术家和列表视图中显示出来，现在我的问题是，如果任何歌曲之前，播放会自动停止并播放新的歌曲哪些用户是当任何用户点击特定项目的歌曲将发挥单击我也想从我的列表视图获取歌曲名和歌手名。
请帮我在这里我的代码
package com.monstertechno.musicplayerappui;
import android.Manifest;
import android.content.ContentResolver;
import android.content.Context;
import android.content.DialogInterface;
import android.content.pm.PackageManager;
import android.database.Cursor;
import android.media.MediaPlayer;
import android.net.Uri;
import android.renderscript.Sampler;
import android.support.annotation.NonNull;
import android.support.v4.app.ActivityCompat;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ImageButton;
import android.widget.ListView;
import android.widget.Toast;
import com.karumi.dexter.Dexter;
import com.karumi.dexter.PermissionToken;
import com.karumi.dexter.listener.PermissionDeniedResponse;
import com.karumi.dexter.listener.PermissionGrantedResponse;
import com.karumi.dexter.listener.PermissionRequest;
import com.karumi.dexter.listener.single.PermissionListener;
import com.sothree.slidinguppanel.SlidingUpPanelLayout;
import com.sothree.slidinguppanel.SlidingUpPanelLayout.PanelState;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
public class MainActivity extends AppCompatActivity {
MediaPlayer mediaPlayer;
private ArrayList<Song> songList;
private ListView songView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
runtimpermission();
songView = (ListView) findViewById(R.id.song_list);
songList = new ArrayList<Song>();
SongAdapter songAdt = new SongAdapter(this, songList);
songView.setAdapter(songAdt);
getSongList();
Collections.sort(songList, new Comparator<Song>() {
public int compare(Song a, Song b) {
return a.getTitle().compareTo(b.getTitle());
}
});
songView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
if(mediaPlayer!=null){
mediaPlayer.release();
}
}
});
}
public void runtimpermission(){
Dexter.withActivity(this)
.withPermission(Manifest.permission.READ_EXTERNAL_STORAGE)
.withListener(new PermissionListener() {
@Override public void onPermissionGranted(PermissionGrantedResponse response) {
Toast.makeText(MainActivity.this, "Permisson Access", Toast.LENGTH_SHORT).show();
}
@Override public void onPermissionDenied(PermissionDeniedResponse response) {
Toast.makeText(MainActivity.this, "Permisson Denied", Toast.LENGTH_SHORT).show();
}
@Override
public void onPermissionRationaleShouldBeShown(PermissionRequest permission, PermissionToken token) {
token.continuePermissionRequest();}
}).check();
}
public void getSongList() {
//retrieve song info
ContentResolver musicResolver = getContentResolver();
Uri musicUri = android.provider.MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
Cursor musicCursor = musicResolver.query(musicUri, null, null, null, null);
if(musicCursor!=null && musicCursor.moveToFirst()){
//get columns
int titleColumn = musicCursor.getColumnIndex
(android.provider.MediaStore.Audio.Media.TITLE);
int idColumn = musicCursor.getColumnIndex
(android.provider.MediaStore.Audio.Media._ID);
int artistColumn = musicCursor.getColumnIndex
(android.provider.MediaStore.Audio.Media.ARTIST);
//add songs to list
do {
long thisId = musicCursor.getLong(idColumn);
String thisTitle = musicCursor.getString(titleColumn);
String thisArtist = musicCursor.getString(artistColumn);
songList.add(new Song(thisId, thisTitle, thisArtist));
}
while (musicCursor.moveToNext());
}
}
}
package com.monstertechno.musicplayerappui;
public class Song {
private long id;
private String title;
private String artist;
public Song(long songID, String songTitle, String songArtist) {
id=songID;
title=songTitle;
artist=songArtist;
}
public long getId() {
return id;
}
public String getTitle() {
return title;
}
public String getArtist() {
return artist;
}
}
package com.monstertechno.musicplayerappui;
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.LinearLayout;
import android.widget.TextView;
import java.util.ArrayList;
public class SongAdapter extends BaseAdapter {
private ArrayList<Song> songs;
private LayoutInflater songInf;
public SongAdapter(Context c, ArrayList<Song> theSongs){
songs=theSongs;
songInf=LayoutInflater.from(c);
}
@Override
public int getCount() {
// TODO Auto-generated method stub
return songs.size();
}
@Override
public Object getItem(int arg0) {
// TODO Auto-generated method stub
return null;
}
@Override
public long getItemId(int arg0) {
// TODO Auto-generated method stub
return 0;
}
@Override
public View getView(int position, View arg1, ViewGroup parent) {
LinearLayout songLay = (LinearLayout)songInf.inflate
(R.layout.musiccustom,parent , false);
// TODO Auto-generated method stub
TextView songView = (TextView)songLay.findViewById(R.id.song_title);
TextView artistView = (TextView)songLay.findViewById(R.id.song_artist);
//get song using position
Song currSong = songs.get(position);
//get title and artist strings
songView.setText(currSong.getTitle());
artistView.setText(currSong.getArtist());
//set position as tag
songLay.setTag(position);
return songLay;
}
}
官方文件说：当你调用stop（），但是，请注意，你不能调用start（）直至你再次准备的MediaPlayer。 https://developer.android.com/guide/topics/media/mediaplayer
所以，你需要做的是在你的onClick（）的ListView的听众再次准备MediaPlayer的实例（对象）。
MediaPlayer mediaPlayer = new
MediaPlayer();
mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
mediaPlayer.setDataSource(url); //use it when your audio is in a network location
mediaPlayer.prepare(); // might take long! (for buffering, etc)
mediaPlayer.start();
为了创建一个URI音频出现在手机存储的文件：
（因为你已经有了基本URI以指向音频文件的文件夹，你需要用它附加的文件名，以获得开放的每个文件）
写以下行（检查拼写）列表项的onClickListener然后准备媒体播放器类
Uri fileUri = Uri.withAppendedPath(musicURI,"the name of audio file");
mediaPlayer.setDataSource(fileUri);
mediaPlayer.prepare(); //
mediaPlayer.start();
更新：通过您的代码搜索后，我发现，你没有得到从光标文件路径。
目前，您只得到MediaStore.Audio.Media.TITLE，MediaStore.Audio.Media._ID和MediaStore.Audio.Media.ARTIST。
String thisDataPath = musicCursor.getString(dataColumn);
现在，您可以轻松地构建每个音频文件的URI副
Uri uri= Uri.parse("file:///"+song.getPath());
无需使用Uri.withAppendPath（）。只需使用线以上，然后设置音乐播放器的数据源
public void getSongList() {
//retrieve song info
ContentResolver musicResolver = getContentResolver();
Uri musicUri = android.provider.MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
Cursor musicCursor = musicResolver.query(musicUri, null, null, null, null);
if(musicCursor!=null && musicCursor.moveToFirst()){
//get columns
int titleColumn = musicCursor.getColumnIndex
(android.provider.MediaStore.Audio.Media.TITLE);
int idColumn = musicCursor.getColumnIndex
(android.provider.MediaStore.Audio.Media._ID);
int artistColumn = musicCursor.getColumnIndex
(android.provider.MediaStore.Audio.Media.ARTIST);
int dataColumn= musicCursor.getColumnIndex
(android.provider.MediaStore.Audio.Media.DATA); //This will get you the column index of the file path
//add songs to list
do {
long thisId = musicCursor.getLong(idColumn);
String thisTitle = musicCursor.getString(titleColumn);
String thisArtist = musicCursor.getString(artistColumn);
String filePath= musicCursor.getString(dataColumn); //Get the file path from the cursor
songList.add(new Song(thisId, thisTitle, thisArtist,filePath)); // Make a list of Song objects along with path of each audio file
}
while (musicCursor.moveToNext());
}
}
列表的onClickListener看起来喜欢 -
songView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
if(mediaPlayer!=null){
mediaPlayer.release();
}
Song song=songList.get(position);
Toast.makeText(getActivity(),song.getFilePath(),Toast.LENGTH_LONG).show();
Uri uri= Uri.parse("file:///"+song.getPath());
mediaPlayer.setDataSource(fileUri);
mediaPlayer.prepare();
mediaPlayer.start();
}
});