android studio期末大作业制作一个高级的·音乐播放器包含源代码

很好，制作一个高级的音乐播放器是一个很好的项目。以下是一个简单的实现，您可以在此基础上进行扩展和改进。以下是一个使用Android Studio开发的音乐播放器的示例代码。

首先，您需要在XML布局文件中定义UI元素，如下所示：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/layout_main"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <LinearLayout
        android:id="@+id/layout_music_controls"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:background="#000000">

        <ImageButton
            android:id="@+id/btn_previous"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_margin="10dp"
            android:background="@null"
            android:src="@drawable/ic_previous" />

        <ImageButton
            android:id="@+id/btn_play_pause"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_margin="10dp"
            android:background="@null"
            android:src="@drawable/ic_play" />

        <ImageButton
            android:id="@+id/btn_next"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_margin="10dp"
            android:background="@null"
            android:src="@drawable/ic_next" />

        <SeekBar
            android:id="@+id/seek_bar"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:paddingLeft="10dp"
            android:paddingRight="10dp" />

        <TextView
            android:id="@+id/text_view_duration"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:textColor="#FFFFFF"
            android:text="00:00" />

    </LinearLayout>

    <ListView
        android:id="@+id/list_view_songs"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_above="@id/layout_music_controls" />

</RelativeLayout>

接下来，您需要为这些UI元素创建适当的变量。

public class MainActivity extends AppCompatActivity implements MediaPlayer.OnCompletionListener {

    private ListView listViewSongs;
    private ImageButton btnPrevious, btnPlayPause, btnNext;
    private SeekBar seekBar;
    private TextView textViewDuration;
    private MediaPlayer mediaPlayer;
    private SongAdapter songAdapter;
    private Handler mHandler = new Handler();
    private List<Song> songs;
    private int currentSongIndex = 0;
    private boolean isPaused = false;

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

        listViewSongs = (ListView) findViewById(R.id.list_view_songs);
        btnPrevious = (ImageButton) findViewById(R.id.btn_previous);
        btnPlayPause = (ImageButton) findViewById(R.id.btn_play_pause);
        btnNext = (ImageButton) findViewById(R.id.btn_next);
        seekBar = (SeekBar) findViewById(R.id.seek_bar);
        textViewDuration = (TextView) findViewById(R.id.text_view_duration);

        mediaPlayer = new MediaPlayer();
        mediaPlayer.setOnCompletionListener(this);

        songs = new ArrayList<>();
        songs.add(new Song("Song 1", R.raw.song1));
        songs.add(new Song("Song 2", R.raw.song2));
        songs.add(new Song("Song 3", R.raw.song3));
        songs.add(new Song("Song 4", R.raw.song4));
        songs.add(new Song("Song 5", R.raw.song5));

        songAdapter = new SongAdapter(this, songs);
        listViewSongs.setAdapter(songAdapter);

        listViewSongs.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                currentSongIndex = position;
                playSong();
            }
        });

        btnPrevious.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if (currentSongIndex > 0) {
                    currentSongIndex--;
                } else {
                    currentSongIndex = songs.size() - 1;
                }
                playSong();
            }
        });

        btnPlayPause.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if (mediaPlayer.isPlaying()) {
                    mediaPlayer.pause();
                    btnPlayPause.setImageResource(R.drawable.ic_play);
                    isPaused = true;
                } else {
                    if (isPaused) {
                        mediaPlayer.start();
                        btnPlayPause.setImageResource(R.drawable.ic_pause);
                    } else {
                        playSong();
                    }
                    isPaused = false;
                }
            }
        });

        btnNext.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if (currentSongIndex < (songs.size() - 1)) {
                    currentSongIndex++;
                } else {
                    currentSongIndex = 0;
                }
                playSong();
            }
        });

        seekBar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
            @Override
            public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
                if (fromUser) {
                    mediaPlayer.seekTo(progress);
                }
            }

            @Override
            public void onStartTrackingTouch(SeekBar seekBar) {

            }

            @Override
            public void onStopTrackingTouch(SeekBar seekBar) {

            }
        });

        updateSeekBar();
    }

    private void playSong() {
        try {
            if (mediaPlayer.isPlaying()) {
                mediaPlayer.stop();
            }

            mediaPlayer.reset();
            Song song = songs.get(currentSongIndex);
            mediaPlayer.setDataSource(getApplicationContext(), Uri.parse("android.resource://" + getPackageName() + "/" + song.getSongResource()));
            mediaPlayer.prepare();
            mediaPlayer.start();
            btnPlayPause.setImageResource(R.drawable.ic_pause);

            updateSeekBar();

        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    private void updateSeekBar() {
        mHandler.postDelayed(mUpdateTimeTask, 100);
    }

    private Runnable mUpdateTimeTask = new Runnable() {
        public void run() {
            long totalDuration = mediaPlayer.getDuration();
            long currentDuration = mediaPlayer.getCurrentPosition();

            textViewDuration.setText(milliSecondsToTimer(currentDuration) + "/" + milliSecondsToTimer(totalDuration));

            int progress = (int) (getProgressPercentage(currentDuration, totalDuration));

            seekBar.setProgress(progress);

            mHandler.postDelayed(this, 100);
        }
    };

    private int getProgressPercentage(long currentDuration, long totalDuration) {
        Double percentage = (double) 0;

        long currentSeconds = (int) (currentDuration / 1000);
        long totalSeconds = (int) (totalDuration / 1000);

        percentage = (((double) currentSeconds) / totalSeconds) * 100;

        return percentage.intValue();
    }

    private String milliSecondsToTimer(long milliseconds) {
        String finalTimerString = "";
        String secondsString = "";

        int hours = (int) (milliseconds / (1000 * 60 * 60));
        int minutes = (int) (milliseconds % (1000 * 60 * 60)) / (1000 * 60);
        int seconds = (int) ((milliseconds % (1000 * 60 * 60)) % (1000 * 60) / 1000);

        if (hours > 0) {
            finalTimerString = hours + ":";
        }

        if (seconds < 10) {
            secondsString = "0" + seconds;
        } else {
            secondsString = "" + seconds;
        }

        finalTimerString = finalTimerString + minutes + ":" + secondsString;

        return finalTimerString;
    }

    @Override
    public void onCompletion(MediaPlayer mp) {
        if (currentSongIndex < (songs.size() - 1)) {
            currentSongIndex++;
            playSong();
        } else {
            currentSongIndex = 0;
            btnPlayPause.setImageResource(R.drawable.ic_play);
        }
    }
}

此代码中，我们定义了一些变量，例如列表视图，前进、播放/暂停和后退按钮，以及音乐播放器。我们还定义了一个适配器，以便将歌曲数据绑定到列表视图。

在onCreate方法中，我们初始化了音乐播放器和适配器，并设置了UI元素的监听器。我们还创建了一个Runnable来更新SeekBar，以便显示当前播放时间和歌曲的总时间。

在playSong方法中，我们使用MediaPlayer类播放所选歌曲，并更新SeekBar。

最后，我们实现了MediaPlayer.OnCompletionListener接口来处理歌曲播放结束时的情况。

这只是一个基本的示例代码，您可以根据需要对其进行扩展和改进。