Merge pull request #463 from lterminiello/fixArithmeticException

fix ArithmeticException in CameraPreview

Author: rkistner

zxing-android-embedded/src/com/journeyapps/barcodescanner/CameraPreview.java

@@ -387,7 +387,17 @@ private void calculateFrames() {
                 frameInPreview.right * previewWidth / surfaceRect.width(),
                 frameInPreview.bottom * previewHeight / surfaceRect.height());
 
-        if (previewFramingRect.width() <= 0 || previewFramingRect.height() <= 0) {
+        if (surfaceRect.width() != 0 && surfaceRect.height() != 0) {
+            previewFramingRect = new Rect(frameInPreview.left * previewWidth / surfaceRect.width(),
+                    frameInPreview.top * previewHeight / surfaceRect.height(),
+                    frameInPreview.right * previewWidth / surfaceRect.width(),
+                    frameInPreview.bottom * previewHeight / surfaceRect.height());
+
+        } else {
+            previewFramingRect = null;
+        }
+
+        if (previewFramingRect == null || previewFramingRect.width() <= 0 || previewFramingRect.height() <= 0) {
             previewFramingRect = null;
             framingRect = null;
             Log.w(TAG, "Preview frame is too small");