【发布时间】：2015-09-27 23:09:45
【问题描述】：
我正在尝试对 MediaPlayer 进行循环进度，因此它在播放时准备和设置进度时是不确定。
我尝试了很多方法，但这是我的最后一个：我更新了AsyncTask<Object, Object, Object> 上的栏。
我使用的类是CircularProgressView，但我尝试换成ProgressBar，行为是相同：
public void startPlaying(final Audio audio, final CircularProgressView progress_view) {
if (!isPLAYING) {
progress_view.setIndeterminate(true);
progress_view.setVisibility(View.VISIBLE);
progress_view.startAnimation();
isPLAYING = true;
audioPlaying = audio;
mp = new MediaPlayer();
new AsyncTask<Object, Object, Object>() {
@Override
protected Object doInBackground(Object... objects) {
try {
mp.prepare();
publishProgress((int)-1);
mediaFileLengthInMilliseconds = mp.getDuration();
mp.start();
while (mp != null && mp.isPlaying()) {
Thread.sleep(100);
publishProgress((int) (mp.getCurrentPosition()));
}
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
@Override
protected void onPreExecute() {
super.onPreExecute();
try {
mp.setDataSource(audio.getFile().getUrl());
} catch (IOException e) {
e.printStackTrace();
}
mp.setOnCompletionListener(new MediaPlayer.OnCompletionListener() {
@Override
public void onCompletion(MediaPlayer mediaPlayer) {
stopPlaying();
publishProgress((int)-2);
}
});
}
@Override
protected void onProgressUpdate(Object... values) {
super.onProgressUpdate(values);
int value = (int)values[0];
if (value == -1) {
progress_view.setIndeterminate(false);
progress_view.setMaxProgress(mediaFileLengthInMilliseconds);
} else if (value == -2) {
progress_view.setVisibility(View.GONE);
} else {
progress_view.setProgress((int) values[0]);
System.out.println("setting: " + values[0]);
}
}
@Override
protected void onPostExecute(Object o) {
super.onPostExecute(o);
}
}.execute();
} else {
isPLAYING = false;
stopPlaying();
}
}
在调试时，ProgressBar 或 CircularProgressView .setProgress() 在音频再现过程中被调用，但它在indeterminate 中仍然被阻止，但progress_view.setIndeterminate(false) 也被调用，并且它不会变得不确定。
音频结束后，ProgressBar 或 CircularProgressView 将获得 100% 的进度。
有什么线索吗？
非常感谢您。
编辑：
正如@Blackbelt 建议的那样，我必须在publishProgress((int)-1); 之前致电mediaFileLengthInMilliseconds = mp.getDuration();
但现在这是行为：
https://drive.google.com/file/d/0B-V0KHNRjbE_b3hkbkwtTXhIeTg/view?usp=sharing
编辑 2：mp.getDuration() 和 mp.getCurrentPosition() 的日志：
或许这更清楚：
在这部分调用：
@Override
protected void onProgressUpdate(Object... values) {
super.onProgressUpdate(values);
int value = (int)values[0];
if (value == -1) {
progress_view.setIndeterminate(false);
progress_view.setMaxProgress(mediaFileLengthInMilliseconds);
Log.i("Stackoverflow:", "setMaxProgress to " + mediaFileLengthInMilliseconds);
} else if (value == -2) {
progress_view.setVisibility(View.GONE);
} else {
progress_view.setProgress((int) values[0]);
Log.i("Stackoverflow:", "setProgress to " + (int)values[0]);
}
}
编辑 3：我正在添加新代码，注释掉函数 setIndeterminate(boolean) 并换成 ProgressBar：
XML：
<ProgressBar
android:id="@+id/progress_view"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:indeterminate="false"
android:progress="40"
android:visibility="gone"
android:layout_alignTop="@+id/play_button"
android:layout_alignLeft="@+id/play_button"
android:layout_alignStart="@+id/play_button"
android:layout_alignRight="@+id/play_button"
android:layout_alignEnd="@+id/play_button"
android:layout_alignBottom="@+id/play_button" />
Java：
public void startPlaying(final Audio audio, final ProgressBar progress_view) {
if (!isPLAYING) {
Log.i("Stackoverflow", "startPlaying called");
audio.put("times_listened", audio.getTimes_Listened() + 1);
audio.saveEventually();
progress_view.setVisibility(View.VISIBLE);
isPLAYING = true;
audioPlaying = audio;
mp = new MediaPlayer();
new AsyncTask<Object, Object, Object>() {
@Override
protected Object doInBackground(Object... objects) {
try {
mp.prepare();
mediaFileLengthInMilliseconds = mp.getDuration();
publishProgress((int)-1);
mp.start();
while (mp != null && mp.isPlaying()) {
Thread.sleep(100);
publishProgress((int) (mp.getCurrentPosition()));
}
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
@Override
protected void onPreExecute() {
super.onPreExecute();
try {
mp.setDataSource(audio.getFile().getUrl());
} catch (IOException e) {
e.printStackTrace();
}
mp.setOnCompletionListener(new MediaPlayer.OnCompletionListener() {
@Override
public void onCompletion(MediaPlayer mediaPlayer) {
stopPlaying();
publishProgress((int)-2);
}
});
}
@Override
protected void onProgressUpdate(Object... values) {
super.onProgressUpdate(values);
int value = (int)values[0];
if (value == -1) {
progress_view.setMax(mediaFileLengthInMilliseconds);
Log.i("Stackoverflow:", "setMaxProgress to " + mediaFileLengthInMilliseconds);
} else if (value == -2) {
progress_view.setVisibility(View.GONE);
} else {
progress_view.setProgress((int) values[0]);
Log.i("Stackoverflow:", "setProgress to " + (int)values[0]);
System.out.println("setting: " + values[0]);
}
}
@Override
protected void onPostExecute(Object o) {
super.onPostExecute(o);
}
}.execute();
} else {
isPLAYING = false;
stopPlaying();
}
}
编辑 4：
我打电话给progress_view.isDeterminate()，它每次都给我回复true。所以我决定在修改进度的时候做：
@Override
protected void onProgressUpdate(Object... values) {
super.onProgressUpdate(values);
int value = (int)values[0];
if (value == -1) {
progress_view.setMax(mediaFileLengthInMilliseconds);
Log.i("Stackoverflow:", "setMaxProgress to " + mediaFileLengthInMilliseconds);
} else if (value == -2) {
progress_view.setVisibility(View.GONE);
} else {
if (progress_view.isIndeterminate()) // LOOK AT THIS
progress_view.setIndeterminate(false);
progress_view.setProgress((int) values[0]);
Log.i("Stackoverflow:", "setProgress to " + (int) values[0]);
Log.i("Stackoverflow", "Indeterminate state: " + progress_view.isIndeterminate());
System.out.println("setting: " + values[0]);
}
}
输出总是：
不确定状态：真
*为什么？ * :'(
【问题讨论】：
标签： android android-mediaplayer android-progressbar