MediaPlayer.isplaying() 方法中的 java.lang.IllegalStateException
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java.lang.IllegalStateException in MediaPlayer.isplaying() method
提问by Sydroid
public static MediaPlayer mp=null;
public static void playGeneric(int name, final ImageButton button,final ImageButton pervious,Context context) {
button.setEnabled(false);
button.setClickable(false);
pervious.setEnabled(false);
pervious.setClickable(false);
try{
if(mp != null && mp.isPlaying())
{
mp.stop();
mp.release();
mp = null;
mp=MediaPlayer.create(context, name);
mp.start();
}
else
{
mp = MediaPlayer.create(context, name);
mp.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
@Override
public void onPrepared(MediaPlayer arg0) {
//mp.prepare();
mp.start();
}
});
mp.setOnCompletionListener(new MediaPlayer.OnCompletionListener() {
@Override
public void onCompletion(MediaPlayer mp) {
// TODO Auto-generated method stub
mp.release();
System.out.println("Object released");
button.setEnabled(true);
button.setClickable(true);
pervious.setEnabled(true);
pervious.setClickable(true);
}
});
}
} catch (IllegalStateException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}catch (SecurityException e) {
// TODO Auto-generated catch block
e.printStackTrace();
e.getMessage();
} catch (NullPointerException e) {
// TODO Auto-generated catch block
e.printStackTrace();
e.getMessage();
}
}
give me java.lang.IllegalStateException on mp.isplaying() method.
在 mp.isplaying() 方法上给我 java.lang.IllegalStateException 。
I want to stop music if it's playing and play another song one after another.
如果音乐正在播放，我想停止播放并一首接一首地播放另一首歌曲。
logcat:
日志猫：
10-14 15:12:05.474: E/MediaPlayer(15411): prepareAsync called in state 8
10-14 15:12:05.474: W/System.err(15411): java.lang.IllegalStateException
10-14 15:12:05.474: W/System.err(15411): at android.media.MediaPlayer.prepare(Native Method)
10-14 15:12:05.474: W/System.err(15411): at com.rogerscenter.LearnReadWriteSpell.Utility.Music.playGeneric(Music.java:93)
10-14 15:12:05.474: W/System.err(15411): at com.rogerscenter.LearnReadWriteSpell.LetterCategory.Letter_Lesson1_activity.onCreate(Letter_Lesson1_activity.java:140)
10-14 15:12:05.474: W/System.err(15411): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
10-14 15:12:05.474: W/System.err(15411): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1586)
10-14 15:12:05.474: W/System.err(15411): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1638)
10-14 15:12:05.474: W/System.err(15411): at android.app.ActivityThread.access00(ActivityThread.java:117)
10-14 15:12:05.474: W/System.err(15411): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:928)
10-14 15:12:05.484: W/System.err(15411): at android.os.Handler.dispatchMessage(Handler.java:99)
10-14 15:12:05.484: W/System.err(15411): at android.os.Looper.loop(Looper.java:123)
10-14 15:12:05.484: W/System.err(15411): at android.app.ActivityThread.main(ActivityThread.java:3647)
10-14 15:12:05.484: W/System.err(15411): at java.lang.reflect.Method.invokeNative(Native Method)
10-14 15:12:05.484: W/System.err(15411): at java.lang.reflect.Method.invoke(Method.java:507)
10-14 15:12:05.484: W/System.err(15411): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
10-14 15:12:05.484: W/System.err(15411): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
10-14 15:12:05.484: W/System.err(15411): at dalvik.system.NativeStart.main(Native Method)
回答by Siddhpura Amit
As android docs suggest that if mp is if has not been initialized at that time java.lang.IllegalStateException will be thrown so you have to initilize first or you have to write
由于android docs建议如果mp是如果当时尚未初始化java.lang.IllegalStateException将被抛出所以你必须先初始化或者你必须写
check out the docs http://developer.android.com/reference/android/media/MediaPlayer.html#isPlaying()
查看文档http://developer.android.com/reference/android/media/MediaPlayer.html#isPlaying()
try like this
像这样尝试
mp=MediaPlayer.create(context, name);
try {
if (mp.isPlaying()) {
mp.stop();
mp.release();
mp=MediaPlayer.create(context, name);
}
mp.start();
} catch (Exception e) {
}
回答by Mester Hassan
Try changing mp.release()into reset(). that could help you.
尝试更改mp.release()为reset(). 那可以帮助你。
回答by Sagar Jethva
use runOnUiThread for mediaRecorder prepare.
使用 runOnUiThread 进行 mediaRecorder 准备。
private boolean prepareMediaRecorder() {
mediaRecorder = new MediaRecorder();
runOnUiThread(new Runnable() {
@Override
public void run() {
mediaRecorder.reset();
mediaRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
mediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.AMR_NB);
mediaRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);
mediaRecorder.setOutputFile(filePath);
try {
mediaRecorder.prepare();
} catch (IOException e) {
mediaRecorder = null;
return;
}
mediaRecorder.start();
recording = true;
}
});
return true;
}
