tooltips about connecting elements are shown only 2 times

refs 1612

org.fortiss.tooling.base.ui/trunk/src/org/fortiss/tooling/base/ui/editor/DiagramEditorBase.java

@@ -106,7 +106,7 @@ import org.fortiss.tooling.kernel.ui.service.IEditPartFactoryService;
  * @author hoelzl
  * @author $Author$
  * @version $Rev$
- * @ConQAT.Rating GREEN Hash: 4F5E3DD53FCF647674A9830DABDE0593
+ * @ConQAT.Rating YELLOW Hash: 9E72ED3F824111F92720F85EF823E3DF
  */
 public class DiagramEditorBase<T extends EObject> extends GEFEditorBase<T> implements
 		IPostSelectionProvider, ContextMenuContextProvider {
@@ -129,6 +129,15 @@ public class DiagramEditorBase<T extends EObject> extends GEFEditorBase<T> imple
 	/** A container for editor actions */
 	private final ActionRegistry actionRegistry = new ActionRegistry();
 
+	/** A counter for the selection of connectors. */
+	private int connectorsSelectionCount;
+
+	/** A counter for the selection of hierarchic elements. */
+	private int hierarchicElementssSelectionCount;
+
+	/** The number of times the hints about creating connections should be displayed. */
+	private static final int HINTS_COUNT = 2;
+
 	/** Selection listener used to update selection actions. */
 	private final ISelectionListener selectionListener = new ISelectionListener() {
 		@Override
@@ -136,10 +145,13 @@ public class DiagramEditorBase<T extends EObject> extends GEFEditorBase<T> imple
 			EditPart ep = SelectionUtils.checkAndPickFirstSafe(selection, EditPart.class);
 			if(ep != null) {
 				Control control = ep.getViewer().getControl();
-				if(ep.getModel() instanceof IConnector) {
+				if(ep.getModel() instanceof IConnector && connectorsSelectionCount < HINTS_COUNT) {
 					control.setToolTipText("Link two connectors by pressing ALT and dragging from source to target.");
-				} else if(ep.getModel() instanceof IHierarchicElement) {
+					connectorsSelectionCount++;
+				} else if(ep.getModel() instanceof IHierarchicElement &&
+						hierarchicElementssSelectionCount < HINTS_COUNT) {
 					control.setToolTipText("Create a connection by pressing ALT and dragging.");
+					hierarchicElementssSelectionCount++;
 				}
 			}
 			updateActions(selectionActions);