Let SwingNumberWidget listen for mouse wheel events

Author: imagejan

src/main/java/org/scijava/ui/swing/widget/SwingNumberWidget.java

@@ -37,6 +37,8 @@
 import java.awt.event.AdjustmentListener;
 import java.awt.event.FocusEvent;
 import java.awt.event.FocusListener;
+import java.awt.event.MouseWheelEvent;
+import java.awt.event.MouseWheelListener;
 import java.math.BigDecimal;
 import java.math.BigInteger;
 import java.text.DecimalFormat;
@@ -67,7 +69,7 @@
  */
 @Plugin(type = InputWidget.class)
 public class SwingNumberWidget extends SwingInputWidget<Number> implements
-	NumberWidget<JPanel>, AdjustmentListener, ChangeListener
+	NumberWidget<JPanel>, AdjustmentListener, ChangeListener, MouseWheelListener
 {
 
 	@Parameter
@@ -110,6 +112,7 @@ public void set(final WidgetModel model) {
 			setToolTip(scrollBar);
 			getComponent().add(scrollBar);
 			scrollBar.addAdjustmentListener(this);
+			scrollBar.addMouseWheelListener(this);
 		}
 		else if (model.isStyle(NumberWidget.SLIDER_STYLE)) {
 			slider =
@@ -121,6 +124,7 @@ else if (model.isStyle(NumberWidget.SLIDER_STYLE)) {
 			setToolTip(slider);
 			getComponent().add(slider);
 			slider.addChangeListener(this);
+			slider.addMouseWheelListener(this);
 		}
 
 		// add spinner widget
@@ -171,6 +175,17 @@ else if (source == spinner) {
 		}
 		updateModel();
 	}
+	
+	// -- MouseWheelListener methods --
+	
+	@Override
+	public void mouseWheelMoved(final MouseWheelEvent e) {
+		int value = getValue().intValue() + e.getWheelRotation();
+		value = Math.min(value, this.get().getMax().intValue());
+		value = Math.max(value, this.get().getMin().intValue());
+		spinner.setValue(value);
+		syncSliders();
+	}
 
 	// -- Helper methods --