Android Media Player SeekBar 不通过歌曲文件搜索

Question

我在使用 Seekbar 时遇到一些问题，加载的第一首歌曲不允许我使用 SeekBar，但是当我加载第二首或第三首歌曲时，SeekBar 会为它们工作。我尝试在加载歌曲 Uri 数据源后初始化 SeekBar，但它仍然表现出相同的行为。

关于如何让 SeekBar 在第一首歌曲上工作有什么想法吗？

谢谢

...

public class MainActivity extends AppCompatActivity {

    final int REQUEST_OPEN_FILE = 1;
    MediaPlayer mediaPlayer = new MediaPlayer();
    Uri audioFileUri;
    /*SeekBar seekBar;*/
    /*TextView SongProgress = findViewById(R.id.SongProgress);*/

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        ...
    }

    ...

    @Override
    public void onActivityResult(int requestCode, int resultCode, Intent data) {

        if (requestCode == REQUEST_OPEN_FILE) {
            if (resultCode == RESULT_OK) {
                audioFileUri = data.getData();
                SeekBar seekBar;
                seekBar = findViewById(R.id.seekbar);
                seekBar.setMax(mediaPlayer.getDuration());
                seekBar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
                    @Override
                    public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
                        seekBar.setProgress(progress);
                        mediaPlayer.seekTo(progress);
                        /*int Minutes=((progress/1000)/60);
                        int Seconds=((progress/1000)%60);
                        int time = Minutes + Seconds;
                        SongProgress.setText(time);*/
                    }


                    @Override
                    public void onStartTrackingTouch(SeekBar seekBar) {

                    }

                    @Override
                    public void onStopTrackingTouch(SeekBar seekBar) {

                    }
                });

                    try {
                        if (mediaPlayer.isPlaying()) {
                            mediaPlayer.reset();
                            mediaPlayer.setDataSource(this, audioFileUri);
                            mediaPlayer.prepare();
                            mediaPlayer.start();
                            Toast.makeText(this, "Was Playing", Toast.LENGTH_SHORT);

                        }
                        else{
                            mediaPlayer.setDataSource(this, audioFileUri);
                            mediaPlayer.prepare();
                            mediaPlayer.start();
                            Toast.makeText(this, "Was not playing", Toast.LENGTH_SHORT);
                        }

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

    ...

    ...
}

Answer 1

好的，我得到了搜索栏进度以随歌曲更新，以便搜索栏在播放时沿着音频文件进行跟踪。这是一个带有处理程序的简单可运行程序，我已将其发布在此处的代码中。您必须有一个可运行的循环来跟踪正在播放的歌曲以更新搜索栏。然后您必须编写一个处理程序来调用该可运行循环。需要注意的一件重要事情是，如果您不在 seekbar onchanged 侦听器中添加 Boolean if(fromUser)，则该线程将导致其播放断断续续，因为它也在更新与 seekBar 更新进度函数相关的进度。

    SeekBar seekBar;
    Handler handler = new Handler();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        ...

        seekBar = (SeekBar) findViewById(R.id.seekbar);

        ...
    }

    ...

    @Override
    public void onActivityResult(int requestCode, int resultCode, Intent data) {

        if (requestCode == REQUEST_OPEN_FILE) {
            if (resultCode == RESULT_OK) {
                audioFileUri = data.getData();
                try {

                    if (mediaPlayer.isPlaying()) {
                        seekBar.setProgress(0);
                        mediaPlayer.reset();
                        mediaPlayer.setDataSource(this, audioFileUri);
                        mediaPlayer.prepare();
                        mediaPlayer.start();
                        seekBar.setMax(mediaPlayer.getDuration()); // Set the Maximum range of the
                        Toast.makeText(this, "Was Playing", Toast.LENGTH_SHORT);
                    } else {
                        seekBar.setProgress(0);
                        mediaPlayer.setDataSource(this, audioFileUri);
                        mediaPlayer.prepare();
                        mediaPlayer.start();
                        seekBar.setMax(mediaPlayer.getDuration()); // Set the Maximum range of the
                        /*seekBar.getVisibility();
                        seekBar.setVisibility(View.INVISIBLE);*/
                        Toast.makeText(this, "Was not playing", Toast.LENGTH_SHORT);
                    }


                } catch (Exception e) {
                    e.printStackTrace();
                }
                int mediaPos = mediaPlayer.getCurrentPosition();
                int mediaMax = mediaPlayer.getDuration();
                seekBar.setMax(mediaMax); // Set the Maximum range of the
                seekBar.setProgress(mediaPos);// set current progress to song's

                handler.removeCallbacks(moveSeekBarThread);
                handler.postDelayed(moveSeekBarThread, 1000);
            }

        }

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

            @Override
            public void onStartTrackingTouch(SeekBar seekBar) {

            }

            @Override
            public void onStopTrackingTouch(SeekBar seekBar) {

            }
        });
    }


private Runnable moveSeekBarThread = new Runnable() {
    public void run() {
        if(mediaPlayer.isPlaying()){
            int mediaPos_new = mediaPlayer.getCurrentPosition();
            int mediaMax_new = mediaPlayer.getDuration();
            seekBar.setMax(mediaMax_new);
            seekBar.setProgress(mediaPos_new);
            handler.postDelayed(this, 100); //Looping the thread after 0.1 second
            // seconds
        }else if(mediaPlayer.getCurrentPosition() == mediaPlayer.getDuration()){}
    }
};

Android Media Player SeekBar 不通过歌曲文件搜索

Android Media Player SeekBar not seeking through songfile

java

media

android

seekbar