Fix clip area when zoomed

Author: brunomnsilva

src/main/java/com/brunomnsilva/smartgraph/containers/ContentZoomPane.java

@@ -76,6 +76,7 @@ public ContentZoomPane(Node content) {
 
         setCenter(this.content = content);
         enablePanAndZoom();
+        enableResizeListener();
     }
 
     public DoubleProperty scaleFactorProperty() {
@@ -100,6 +101,11 @@ private static double boundValue(double value, double min, double max) {
         return value;
     }
 
+    private void enableResizeListener() {
+        this.widthProperty().addListener((observableValue, oldValue, newValue) -> clipArea());
+        this.heightProperty().addListener((observableValue, oldValue, newValue) -> clipArea());
+    }
+
     private void enablePanAndZoom() {
 
         setOnScroll((ScrollEvent event) -> {
@@ -175,15 +181,15 @@ private void clipArea() {
         setClip(new Rectangle(width,height));
     }
 
-
+    /**
+     * Keeps track of mouse drag action.
+     */
     private static class DragContext {
-
         double mouseAnchorX;
         double mouseAnchorY;
 
         double translateAnchorX;
         double translateAnchorY;
-
     }
 
 }