setOutputFormat called in an invalid state: 1

Posted 2020-10-24 llguanli

在编写一个简单的录像应用程序的时候，爆出例如以下异常：

E MediaRecorder: setOutputFormat called in an invalid state: 1
E androidRuntime: java.lang.IllegalStateException
E AndroidRuntime: at android.media.MediaRecorder.setOutputFormat(Native Method)

由于code是全然依照google的Demo写的，认为比較奇怪。

看描写叙述是说setOutputFormat的时候，状态应该错乱了。最后又看了一下google文档，原因在于google对于设定MediaRecorder是有要求的：

所以在写代码的时候应该全然依照人家要求的设定顺序来写，详细例如以下：

    	mCamera.unlock();
    	mProfile = CamcorderProfile.get(CamcorderProfile.QUALITY_HIGH);
    	
    	//1st. Initial state
    	mMediaRecorder = new MediaRecorder();
    	mMediaRecorder.setCamera(mCamera);
    	
    	//2st. Initialized state
    	mMediaRecorder.setAudiosource(MediaRecorder.AudioSource.CAMCORDER);
    	mMediaRecorder.setVideoSource(MediaRecorder.VideoSource.CAMERA);
    	
    	//3st. config
        mMediaRecorder.setOutputFormat(mProfile.fileFormat);
        mMediaRecorder.setAudioEncoder(mProfile.audioCodec);
        mMediaRecorder.setVideoEncoder(mProfile.videoCodec);
        mMediaRecorder.setOutputFile("/sdcard/FBVideo.3gp");
        mMediaRecorder.setVideoSize(mProfile.videoFrameWidth, mProfile.videoFrameHeight);
        mMediaRecorder.setVideoFrameRate(mProfile.videoFrameRate);
        mMediaRecorder.setVideoEncodingBitRate(mProfile.videoBitRate);
        mMediaRecorder.setAudioEncodingBitRate(mProfile.audioBitRate);
        mMediaRecorder.setAudioChannels(mProfile.audioChannels);
        mMediaRecorder.setAudioSamplingRate(mProfile.audioSampleRate);

    	
    	mMediaRecorder.setPreviewDisplay(mHolder.getSurface());
    	
    	try {
			mMediaRecorder.prepare();
			mMediaRecorder.start();
		} catch (IllegalStateException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}