android studio期末大作业制作一个音乐播放器包括代码

很高兴能帮助你！下面是一个简单的Android音乐播放器的示例代码：

首先，在你的布局文件中添加以下内容：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <ListView
        android:id="@+id/listView"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_alignParentTop="true"
        android:layout_above="@+id/layout"
        android:dividerHeight="1dp"
        android:divider="#cccccc" />

    <LinearLayout
        android:id="@+id/layout"
        android:layout_width="match_parent"
        android:layout_height="50dp"
        android:layout_alignParentBottom="true"
        android:orientation="horizontal"
        android:background="#ffffff"
        android:padding="5dp">

        <ImageView
            android:id="@+id/prev"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:src="@drawable/prev"
            android:layout_gravity="center_vertical"
            android:layout_marginRight="10dp" />

        <ImageView
            android:id="@+id/play"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:src="@drawable/play"
            android:layout_gravity="center_vertical"
            android:layout_marginRight="10dp" />

        <ImageView
            android:id="@+id/next"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:src="@drawable/next"
            android:layout_gravity="center_vertical" />

        <TextView
            android:id="@+id/title"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Title"
            android:textSize="16sp"
            android:textColor="#000000"
            android:layout_gravity="center_vertical"
            android:layout_weight="1" />

    </LinearLayout>

</RelativeLayout>

然后，在你的Activity中添加以下代码：

public class MainActivity extends AppCompatActivity {

    private ListView listView;
    private ImageView prev, play, next;
    private TextView title;

    private MediaPlayer mediaPlayer;
    private boolean isPlaying = false;

    private int currentSongIndex = 0;

    private String[] songs = {
            "song1.mp3",
            "song2.mp3",
            "song3.mp3"
    };

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

        listView = findViewById(R.id.listView);
        prev = findViewById(R.id.prev);
        play = findViewById(R.id.play);
        next = findViewById(R.id.next);
        title = findViewById(R.id.title);

        mediaPlayer = new MediaPlayer();
        mediaPlayer.setOnCompletionListener(new MediaPlayer.OnCompletionListener() {
            @Override
            public void onCompletion(MediaPlayer mediaPlayer) {
                isPlaying = false;
                play.setImageResource(R.drawable.play);
            }
        });

        final ArrayAdapter<String> adapter = new ArrayAdapter<>(this, android.R.layout.simple_list_item_1, songs);
        listView.setAdapter(adapter);

        listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
                try {
                    mediaPlayer.reset();
                    mediaPlayer.setDataSource(MainActivity.this, Uri.parse("android.resource://" + getPackageName() + "/raw/" + songs[i]));
                    mediaPlayer.prepare();
                    mediaPlayer.start();
                    isPlaying = true;
                    currentSongIndex = i;
                    play.setImageResource(R.drawable.pause);
                    title.setText(songs[i]);
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        });

        prev.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                if (currentSongIndex > 0) {
                    currentSongIndex--;
                    listView.setSelection(currentSongIndex);
                    listView.performItemClick(listView.getAdapter().getView(currentSongIndex, null, null), currentSongIndex, listView.getAdapter().getItemId(currentSongIndex));
                }
            }
        });

        next.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                if (currentSongIndex < songs.length - 1) {
                    currentSongIndex++;
                    listView.setSelection(currentSongIndex);
                    listView.performItemClick(listView.getAdapter().getView(currentSongIndex, null, null), currentSongIndex, listView.getAdapter().getItemId(currentSongIndex));
                }
            }
        });

        play.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                if (isPlaying) {
                    mediaPlayer.pause();
                    isPlaying = false;
                    play.setImageResource(R.drawable.play);
                } else {
                    mediaPlayer.start();
                    isPlaying = true;
                    play.setImageResource(R.drawable.pause);
                }
            }
        });
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        mediaPlayer.release();
    }
}

这段代码创建了一个简单的音乐播放器，其中包括一个ListView来列出所有可用的歌曲，ImageViews来控制播放，暂停，上一首和下一首，以及一个TextView来显示当前播放的歌曲标题。它还使用了Android的MediaPlayer类来播放歌曲。

请注意，此示例仅包含基本的播放功能，如果您想要更多高级的功能，您需要自己添加它们。