调用相机异常app passed NULL surface java.lang.RuntimeException: startPreview failed

调用系统相机扫码时报错：app passed NULL surface   java.lang.RuntimeException: startPreview failed

D/Camera: app passed NULL surface
W/System.err: java.lang.RuntimeException: startPreview failed
W/System.err:     at android.hardware.Camera.startPreview(Native Method)
W/System.err:     at com.gritview.mycamera.CameraManager.startPreview(CameraManager.java:116)
W/System.err:     at com.gritview.mycamera.CameraPreview.startCameraPreview(CameraPreview.java:97)
W/System.err:     at com.gritview.mycamera.CameraPreview.surfaceChanged(CameraPreview.java:114)
W/System.err:     at android.view.SurfaceView.updateWindow(SurfaceView.java:621)
W/System.err:     at android.view.SurfaceView.access$000(SurfaceView.java:93)
W/System.err:     at android.view.SurfaceView$3.onPreDraw(SurfaceView.java:182)
W/System.err:     at android.view.ViewTreeObserver.dispatchOnPreDraw(ViewTreeObserver.java:864)
W/System.err:     at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:2138)
W/System.err:     at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1245)
W/System.err:     at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:6320)
W/System.err:     at android.view.Choreographer$CallbackRecord.run(Choreographer.java:791)
W/System.err:     at android.view.Choreographer.doCallbacks(Choreographer.java:591)
W/System.err:     at android.view.Choreographer.doFrame(Choreographer.java:561)
W/System.err:     at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:777)
W/System.err:     at android.os.Handler.handleCallback(Handler.java:730)
W/System.err:     at android.os.Handler.dispatchMessage(Handler.java:92)
W/System.err:     at android.os.Looper.loop(Looper.java:137)
W/System.err:     at android.app.ActivityThread.main(ActivityThread.java:5414)
W/System.err:     at java.lang.reflect.Method.invokeNative(Native Method)
W/System.err:     at java.lang.reflect.Method.invoke(Method.java:525)
W/System.err:     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1187)
W/System.err:     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1003)
W/System.err:     at dalvik.system.NativeStart.main(Native Method)
I/Choreographer: Skipped 629 frames!  The application may be doing too much work on its main thread.
W/System.err: java.lang.RuntimeException: startPreview failed
W/System.err:     at android.hardware.Camera.startPreview(Native Method)
W/System.err:     at com.gritview.mycamera.CameraManager.startPreview(CameraManager.java:116)
W/System.err:     at com.gritview.mycamera.CameraPreview.startCameraPreview(CameraPreview.java:97)
W/System.err:     at com.gritview.mycamera.CameraPreview.start(CameraPreview.java:80)

 

原始代码：

  /**
     * Camera start preview.
     */
    public boolean start() {
        try {
            mCameraManager.openDriver();
        } catch (Exception e) {
            return false;
        }
        mPreviewCallback.onStart();

        if (mSurfaceView == null) {
            mSurfaceView = new SurfaceView(getContext());
            addView(mSurfaceView, new LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT));

            SurfaceHolder holder = mSurfaceView.getHolder();
            holder.addCallback(this);
            holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
        }
        startCameraPreview(mSurfaceView.getHolder());
        return true;
    }

其中： mCameraManager.openDriver();中的代码是初始化camera对象的：

/**
     * Opens the mCamera driver and initializes the hardware parameters.
     *
     * @throws Exception ICamera open failed, occupied or abnormal.
     */
    public synchronized void openDriver() throws Exception {
        if (mCamera != null) return;

        mCamera = Camera.open();
        if (mCamera == null) throw new IOException("The camera is occupied.");

        mConfiguration.initFromCameraParameters(mCamera);

        Camera.Parameters parameters = mCamera.getParameters();
        List<Camera.Size> supportedPreviewSizes = parameters.getSupportedPreviewSizes();
        for (Camera.Size size:supportedPreviewSizes) {
            System.out.println(size.width + "  -------    " + size.height);
        }
        String parametersFlattened = parameters == null ? null : parameters.flatten();
        try {
            mConfiguration.setDesiredCameraParameters(mCamera, false);
        } catch (RuntimeException re) {
            if (parametersFlattened != null) {
                parameters = mCamera.getParameters();
                parameters.unflatten(parametersFlattened);
                try {
                    mCamera.setParameters(parameters);
                    mConfiguration.setDesiredCameraParameters(mCamera, true);
                } catch (RuntimeException e) {
                    e.printStackTrace();
                }
            }
        }

    }

 

上面的代码在Android 有些版本上运行是没有问题，但是在使用三星 Android4.3测试的时候，会报异常，该异常的主要原因是：

在初始化Camera对象之前，没有指定SurfaceHolder对象的类型，所以只需要将上面的代码顺序调换一下即可：

正确代码如下：

 /**
     * Camera start preview.
     */
    public boolean start() {

        if (mSurfaceView == null) {
            mSurfaceView = new SurfaceView(getContext());
            addView(mSurfaceView, new LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT));

            SurfaceHolder holder = mSurfaceView.getHolder();
            holder.addCallback(this);
            holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
        }
        startCameraPreview(mSurfaceView.getHolder());

        
        try {
            mCameraManager.openDriver();
        } catch (Exception e) {
            return false;
        }
        mPreviewCallback.onStart();
        
        
        return true;
    }