媒体播放器在我的代码中不起作用

Question

带音频的列表视图无法播放

你好，你好吗？我正在尝试制作音频列表视图，一切似乎都按预期进行，但是当我单击列表项时，音频应该会重现，但它却出现了 "the app stopped working" 我不明白我的代码有什么问题，有人可以提供帮助我有时会伤脑筋，但我无法解决这个问题。下面是 logcat，然后是我的代码，请有人帮我让它工作。 -谢谢

Logcat

MainActivity.class

public class MainActivity extends AppCompatActivity {
    ListView lv;
    MediaPlayer mp;

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

        lv = findViewById(R.id.lv);
        mp = new MediaPlayer();

        ArrayList<memes> item = new ArrayList<>();

        item.add(new memes("Gemidão", R.raw.gemidaoremix));
        item.add(new memes("Nunca nem vi", R.raw.nuncanemvi));


        ArrayAdapter<memes> adapter = new ArrayAdapter<>(this, android.R.layout.simple_list_item_1, item);
        lv.setAdapter(adapter);

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

        lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> adapterView, View view,
                                    int position, long id) {
                playSong(position);

            }
        });
    }


    public void playSong(int songIndex) {

        mp.reset();
        int[] resID = new int[0];
        mp = MediaPlayer.create(this, resID[songIndex]);

        mp.start();
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        mp.release();
    }


    }

memes.class

public class memes{

    private String nome;
    private int resID;

    memes(String nome, int resID){

        this.nome = nome;
        this.resID = resID;
    }

    public String getNome(){
        return nome;
    }

    public int getResId(){
        return resID;
    }

    @Override
    public String toString(){
        return nome;
    }

}

Answer 1

使用如下代码：

MediaPlayer mediaPlayer = MediaPlayer.create(this, R.raw.song);

播放：

mediaPlayer.start();

暂停：

mediaPlayer.pause();

Answer 2

您的代码存在的问题是您声明了一个单独的未填充原始资源数组。

int[] resID = new int[0];
mp = MediaPlayer.create(this, resID[songIndex]);

解决方案

由于您使用 arraylist 来填充 ListView，因此您需要从 Arraylist 本身获取资源。解决方案将是这样的：

public class MainActivity extends AppCompatActivity {

    ListView lv;
    MediaPlayer mp;
    ArrayList<Memes> item;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        lv = findViewById(R.id.lv);
        mp = new MediaPlayer();

        item = new ArrayList<>();

        item.add(new Memes("Gemidão", R.raw.gemidaoremix));
        item.add(new Memes("Nunca nem vi", R.raw.nuncanemvi));


        ArrayAdapter<Memes> adapter = new ArrayAdapter<>(this, android.R.layout.simple_list_item_1, item);
        lv.setAdapter(adapter);

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

        lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> adapterView, View view,
                                    int position, long id) {
                playSong(position);

            }
        });
    }

    public void playSong(int songIndex) {
        mp.reset();
        mp = MediaPlayer.create(this, item.get(songIndex).getResId());
        mp.start();
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        mp.release();
    }


}

Answer 3

您需要处理资源文件，您可以创建另一种方法来填充您的歌曲列表，您的问题来自 int[] resID = new int[0]; 您使用的是空数组。

另见 Supported Media Formats

添加

int[] songs={R.raw.gemidaoremix,R.raw.nuncanemvi};

将songs用作播放列表

更新

public class MainActivity extends AppCompatActivity {
    ListView lv;
    MediaPlayer mp;
    int[] songs={R.raw.gemidaoremix,R.raw.nuncanemvi};
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        lv = findViewById(R.id.lv);
        mp = new MediaPlayer();

        ArrayList<memes> item = new ArrayList<>();

        item.add(new memes("Gemidão", R.raw.gemidaoremix));
        item.add(new memes("Nunca nem vi", R.raw.nuncanemvi));


        ArrayAdapter<memes> adapter = new ArrayAdapter<>(this, android.R.layout.simple_list_item_1, item);
    lv.setAdapter(adapter);

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

        lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> adapterView, View view,
                                int position, long id) {
                playSong(position);

            }
        });
    }


public void playSong(int songIndex) {

    mp.reset();
    mp = MediaPlayer.create(this, songs[songIndex]);

    mp.start();
}

@Override
public void onDestroy() {
    super.onDestroy();
    mp.release();
}

}

媒体播放器在我的代码中不起作用

media player does not work in my code

java

android

android-mediaplayer

带音频的列表视图无法播放

MainActivity.class

memes.class