Add getAnnotatationBackgroundColor()

* Enable re-use of color scheme also for other editors that embed
  annotations

Issue-Ref: 3696
Issue-Url: https://af3-developer.fortiss.org/issues/3696



Signed-off-by: Simon Barner <barner@fortiss.org>

org.fortiss.tooling.base.ui/src/org/fortiss/tooling/base/ui/annotation/labelprovider/.ratings

-AnnotationLabelProvider.java b45aa4fcfb72726a4c43d2053a713aa5f6b3b7b5 GREEN
+AnnotationLabelProvider.java 27d5bbb02d122e603abd158fa5a1fb39e79b0dc5 YELLOW
 CheckBoxLabelProvider.java 4030bef65a3b919cb087828b4616e5c966380e3e GREEN
 ElementCommentLabelProvider.java 76aa6e9b930ce5680607852fd776172942c89ce5 GREEN
 ElementLabelProviderBase.java f33502f73033ebdf30316df627e8a9c87e7d1b28 GREEN

org.fortiss.tooling.base.ui/src/org/fortiss/tooling/base/ui/annotation/labelprovider/AnnotationLabelProvider.java

@@ -35,7 +35,7 @@ import org.fortiss.tooling.base.ui.annotation.view.IAnnotationViewPart;
 public class AnnotationLabelProvider extends LabelProviderBase {
 
 	/** Background color for annotations that cannot be edited (and that are not derived). */
-	private static final Color READ_ONLY_ANNOTATION_BACKGROUND_COLOR =
+	public static final Color READ_ONLY_ANNOTATION_BACKGROUND_COLOR =
 			SWTResourceManager.getColor(230, 230, 230);
 
 	/** Background color for derived (computed) annotations. */
@@ -96,21 +96,33 @@ public class AnnotationLabelProvider extends LabelProviderBase {
 	/** {@inheritDoc} */
 	@Override
 	public Color getBackground(Object element) {
+		Color color = super.getBackground(element);
 		if(element instanceof AnnotationEntry) {
 			AnnotationEntry annotationEntry = (AnnotationEntry)element;
 			if(annotationEntry.getModelElement().equals(viewPart.getCurrentlySelectedObject())) {
-				return super.getBackground(element);
+				return color;
 			}
 
-			if(!annotationEntry.canEdit(clazz)) {
-				if(IDerivedAnnotation.class.isAssignableFrom(clazz) &&
-						annotationEntry.getSpecificationValue(clazz) != null) {
-					return DERIVED_ANNOTATION_BACKGROUND_COLOR;
-				}
-				return READ_ONLY_ANNOTATION_BACKGROUND_COLOR;
-			}
+			return getAnnotatationBackgroundColor(annotationEntry, clazz, color);
+		}
+		return color;
+	}
+
+	/**
+	 * Returns the background {@link Color} for the {@link AnnotationEntry} of the given
+	 * {@code type}. The method returns dedicated colors for special cases such as read-only or
+	 * "derived" annotations. Otherwise, the provided {@code defaultColor} is returned.
+	 */
+	public static Color getAnnotatationBackgroundColor(AnnotationEntry annotationEntry,
+			Class<? extends IAnnotatedSpecification> type, Color defaultColor) {
+		if(annotationEntry.canEdit(type)) {
+			return defaultColor;
+		}
+		if(IDerivedAnnotation.class.isAssignableFrom(type) &&
+				annotationEntry.getSpecificationValue(type) != null) {
+			return DERIVED_ANNOTATION_BACKGROUND_COLOR;
 		}
-		return super.getBackground(element);
+		return READ_ONLY_ANNOTATION_BACKGROUND_COLOR;
 	}
 
 	/**