title: Android custom camera issue in some devices
body: <p>Hi, I have a custom camera where I have click button, when clicked it captures the image... Everything is fine but in some devices the preview is stretching and also the preview is overlaying half the screen and flickering... some wierd unwanted effect. How to fix this? </p>
  
  <p>This is my code:</p>
  
  <p>Camera Activity:</p>
  
  <pre><code>preview = new Preview(this, (SurfaceView) findViewById(R.id.surfaceView));
  
  preview.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT));
  
  ((FrameLayout) findViewById(R.id.preview)).addView(preview);
  
  preview.setKeepScreenOn(true);
  
  buttonClick = (Button) findViewById(R.id.buttonClick);
  
  buttonClick.setOnClickListener(new OnClickListener() {
      public void onClick(View v) {
          // preview.camera.takePicture(shutterCallback, rawCallback, jpegCallback);
          camera.takePicture(shutterCallback, rawCallback, jpegCallback);
          // camera.setDisplayOrientation(90);
          }
  });
  </code></pre>
  
  <p>Preview class:</p>
  
  <pre><code>class Preview extends ViewGroup implements SurfaceHolder.Callback {
      private final String TAG = "Preview";
  
      SurfaceView mSurfaceView;
      SurfaceHolder mHolder;
      Size mPreviewSize;
      List&lt;Size&gt; mSupportedPreviewSizes;
      Camera mCamera;
  
      @SuppressWarnings("deprecation")
      Preview(Context context, SurfaceView sv) {
          super(context);
  
          mSurfaceView = sv;
          // addView(mSurfaceView);
  
          mHolder = mSurfaceView.getHolder();
          mHolder.addCallback(this);
          mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
      }
  
      public void setCamera(Camera camera) {
          mCamera = camera;
          if (mCamera != null) {
  
              // get Camera parameters
              Camera.Parameters params = mCamera.getParameters();
  
              mSupportedPreviewSizes = params.getSupportedPreviewSizes();
              requestLayout();
  
              List&lt;String&gt; focusModes = params.getSupportedFocusModes();
              if (focusModes.contains(Camera.Parameters.FOCUS_MODE_AUTO)) {
                  // set the focus mode
                  params.setFocusMode(Camera.Parameters.FOCUS_MODE_AUTO);
                  // set Camera parameters
                  mCamera.setParameters(params);
              }
          }
      }
  
      @Override
      protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
          // We purposely disregard child measurements because act as a
          // wrapper to a SurfaceView that centers the camera preview instead
          // of stretching it.
          final int width = resolveSize(getSuggestedMinimumWidth(), widthMeasureSpec);
          final int height = resolveSize(getSuggestedMinimumHeight(), heightMeasureSpec);
          setMeasuredDimension(width, height);
  
          if (mSupportedPreviewSizes != null) {
              mPreviewSize = getOptimalPreviewSize(mSupportedPreviewSizes, width, height);
          }
      }
  
      @Override
      protected void onLayout(boolean changed, int l, int t, int r, int b) {
          if (changed &amp;&amp; getChildCount() &gt; 0) {
              final View child = getChildAt(0);
  
              final int width = r - l;
              final int height = b - t;
  
              int previewWidth = width;
              int previewHeight = height;
              if (mPreviewSize != null) {
                  previewWidth = mPreviewSize.width;
                  previewHeight = mPreviewSize.height;
              }
  
              // Center the child SurfaceView within the parent.
              if (width * previewHeight &gt; height * previewWidth) {
                  final int scaledChildWidth = previewWidth * height / previewHeight;
                  child.layout((width - scaledChildWidth) / 2, 0, (width + scaledChildWidth) / 2, height);
              } else {
                  final int scaledChildHeight = previewHeight * width / previewWidth;
                  child.layout(0, (height - scaledChildHeight) / 2, width, (height + scaledChildHeight) / 2);
              }
          }
      }
  
      public void surfaceCreated(SurfaceHolder holder) {
          // The Surface has been created, acquire the camera and tell it where
          // to draw.
          try {
              if (mCamera != null) {
                  mCamera.setPreviewDisplay(holder);
              }
          } catch (IOException exception) {
              Log.e(TAG, "IOException caused by setPreviewDisplay()", exception);
          }
      }
  
      public void surfaceDestroyed(SurfaceHolder holder) {
          // Surface will be destroyed when we return, so stop the preview.
          if (mCamera != null) {
              mCamera.stopPreview();
          }
      }
  
      private Size getOptimalPreviewSize(List&lt;Size&gt; sizes, int w, int h) {
          final double ASPECT_TOLERANCE = 0.1;
          double targetRatio = (double) w / h;
          if (sizes == null)
              return null;
  
          Size optimalSize = null;
          double minDiff = Double.MAX_VALUE;
  
          int targetHeight = h;
  
          // Try to find an size match aspect ratio and size
          for (Size size : sizes) {
              double ratio = (double) size.width / size.height;
              if (Math.abs(ratio - targetRatio) &gt; ASPECT_TOLERANCE)
                  continue;
              if (Math.abs(size.height - targetHeight) &lt; minDiff) {
                  optimalSize = size;
                  minDiff = Math.abs(size.height - targetHeight);
              }
          }
  
          // Cannot find the one match the aspect ratio, ignore the requirement
          if (optimalSize == null) {
              minDiff = Double.MAX_VALUE;
              for (Size size : sizes) {
                  if (Math.abs(size.height - targetHeight) &lt; minDiff) {
                      optimalSize = size;
                      minDiff = Math.abs(size.height - targetHeight);
                  }
              }
          }
          return optimalSize;
      }
  
      public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
          if (mCamera != null) {
              Camera.Parameters parameters = mCamera.getParameters();
              parameters.setPreviewSize(mPreviewSize.width, mPreviewSize.height);
              requestLayout();
  
              mCamera.setParameters(parameters);
              mCamera.startPreview();
          }
      }
  
  }
  </code></pre>