Android-MediaRecorder-应用程序失去了表面

我首先尝试使用以下内容创建SurfaceView：

SurfaceView sv = new SurfaceView(context);
// Get a surface
surfaceHolder = sv.getHolder();
// tells Android that this surface will have its data constantly
// replaced
surfaceHolder.addCallback(this);
surfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
WindowManager wm = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
LayoutParams params = new WindowManager.LayoutParams(WindowManager.LayoutParams.WRAP_CONTENT,
                WindowManager.LayoutParams.WRAP_CONTENT,
                WindowManager.LayoutParams.TYPE_SYSTEM_OVERLAY,
                WindowManager.LayoutParams.FLAG_WATCH_OUTSIDE_TOUCH,
                PixelFormat.TRANSLUCENT);        
wm.addView(sv, params);

然后试着准备录音机：

try {
    camera.unlock();

    mediaRecorder = new MediaRecorder();

    mediaRecorder.setCamera(camera);
    mediaRecorder.setAudioSource(MediaRecorder.AudioSource.CAMCORDER);
    mediaRecorder.setVideoSource(MediaRecorder.VideoSource.CAMERA);
    mediaRecorder.setProfile(CamcorderProfile
                .get(CamcorderProfile.QUALITY_HIGH));

    mediaRecorder.setOutputFile(getOutputMediaFile(MEDIA_TYPE_VIDEO,
                appName).toString());

    mediaRecorder.setPreviewDisplay(surfaceHolder.getSurface());

    mediaRecorder.prepare();
} catch (IllegalStateException e) {
    releaseMediaRecorder();
    Log.d(TAG,
        "IllegalStateException preparing MediaRecorder: "
                        + e.getMessage());
    return false;
} catch (IOException e) {
    releaseMediaRecorder();
    Log.d(TAG, "IOException preparing MediaRecorder: " + e.getMessage());

    return false;
}

return true;

---

但我得到一个错误“应用程序失去了表面”，尽管我可以看到预览正在工作。为什么会这样？

可能的原因是，只有在MediaRecorder实例创建之后，才会完全创建Surface实例

---

解决方案是将SurfaceView初始化（有问题的第一段代码）放在activity中的onStart（）中。它将保证在MediaRecorder初始化之前完成具有所有相应回调的曲面的创建

是的，我确认这种行为。首先，必须使用camera.setPreviewDisplay（holder）和camera.startPreview（）初始化相机。在预览曲面中显示摄像头图像后，可以调用camera.unlock（）和new MediaRecorder（）.setCamera（摄像头）。