Question

我有一个应用程序，其中AlertDialog在某种情况下弹出。我想在它显示的时候附上一个声音。我的活动名为NfcScannerActivity。

我正在尝试使用MediaPlayer播放声音，但它不会播放。该文件是meep2.mp3，位于thr Raw文件夹中。任何想法为什么不玩？

感谢。

AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(
                                    NfcscannerActivity.this);

                                // set title
                                alertDialogBuilder.setTitle("Sign In Alert ");

                                // set dialog message
                                alertDialogBuilder
                                    .setMessage("You have just signed out from this tag. ( " + tagUserName + " )" +
                                            " Click OK to sign back in at this client or click CANCEL to decline the sign in")
                                    .setCancelable(false)
                                    .setPositiveButton("Ok",new DialogInterface.OnClickListener() {
                                        public void onClick(DialogInterface dialog,int id) {

                                            //do something

                                        }
                                      })
                                    .setNegativeButton("Cancel",new DialogInterface.OnClickListener() {
                                        public void onClick(DialogInterface dialog,int id) {
                                            // if this button is clicked, just close
                                            // the dialog box and do nothing

                                            dialog.cancel();

                                            Log.e(TAG, "Cancelled the transaction as already signed out within last 2 mins on same tag");
                                        }
                                    });

                                    // create alert dialog
                                    AlertDialog alertDialog = alertDialogBuilder.create();

                                    try{
                                    // show it
                                    alertDialog.show();


                                    MediaPlayer mediaPlayer = MediaPlayer.create(NfcscannerActivity.this, R.raw.meep2); 
                                    mediaPlayer.prepare();
                                    mediaPlayer.start();
                                    //mediaPlayer.release();
                                    //mediaPlayer = null; 

                                    }catch(Exception e){

                                        //ignore
                                    }

[编辑]

final MediaPlayer mediaPlayer = MediaPlayer.create(NfcscannerActivity.this, R.raw.alert); 
                                    mediaPlayer.setOnCompletionListener(new OnCompletionListener() {

                                        @Override
                                        public void onCompletion(MediaPlayer mp) {

                                            mp.release();

                                        }
                                    });
                                    mediaPlayer.start();

Answer 1

根据MediaPlayer.create(..)的{{3}}，您无需再致电mediaPlayer.prepare()。
但是，您可以实施Documentation，可以使用MediaPlayer.onCompletionListener注册到MediaPlayer。在此回调中，您应该使用MediaPlayer释放mediaPlayer.release()的资源。

媒体播放器不在警报对话框中播放文件

1 个答案: