diff --git a/AlgebraicDataflowArchitectureModel/src/application/editor/Editor.java b/AlgebraicDataflowArchitectureModel/src/application/editor/Editor.java
index 63702cd..ab13d4d 100644
--- a/AlgebraicDataflowArchitectureModel/src/application/editor/Editor.java
+++ b/AlgebraicDataflowArchitectureModel/src/application/editor/Editor.java
@@ -127,7 +127,7 @@
 			graph.getModel().addListener(mxEvent.CHANGE, curChangeEventListener);
 		}
 		curStage = nextStage;
-		//		notifyStageChangeListeners();	// <- roop?
+		notifyStageChangeListeners();
 		return true;
 	}
 	
@@ -176,7 +176,6 @@
 		
 		model = null;
 		((DataFlowModelingStage) curStage).clear();
-		notifyStageChangeListeners();
 		
 		curFilePath = null;
 		curFileName = null;
@@ -218,7 +217,6 @@
 					
 					// Change to the push/pull selection stage, analyze the data transfer model and construct a data-flow graph.
 					changeStage(STAGE_PUSH_PULL_SELECTION);
-					notifyStageChangeListeners();
 					
 					curFilePath = file.getAbsolutePath();
 					curFileName = file.getName();
@@ -255,7 +253,6 @@
 				
 				// Change to the push/pull selection stage, analyze the data transfer model and construct a data-flow graph.
 				changeStage(STAGE_PUSH_PULL_SELECTION);
-				notifyStageChangeListeners();
 				
 				curFilePath = file.getAbsolutePath();
 				curFileName = file.getName();
@@ -427,7 +424,6 @@
 		
 		((DataFlowModelingStage) curStage).addIdentifierTemplate(res);
 		model = ((DataFlowModelingStage) curStage).getModel();
-		notifyStageChangeListeners();
 	}
 
 	public void addChannelGenerator(DataTransferChannelGenerator channelGen) {
@@ -437,7 +433,7 @@
 		
 		((DataFlowModelingStage) curStage).addChannelGenerator(channelGen);
 		model = ((DataFlowModelingStage) curStage).getModel();
-		notifyStageChangeListeners();
+
 	}
 
 	public void addIOChannelGenerator(DataTransferChannelGenerator ioChannelGen) {
@@ -447,7 +443,6 @@
 		
 		((DataFlowModelingStage) curStage).addIOChannelGenerator(ioChannelGen);
 		model = ((DataFlowModelingStage) curStage).getModel();
-		notifyStageChangeListeners();
 	}
 
 	public void addFormulaChannelGenerator(FormulaChannelGenerator formulaChannelGen) {
@@ -457,7 +452,6 @@
 		
 		((DataFlowModelingStage) curStage).addFormulaChannelGenerator(formulaChannelGen);
 		model = ((DataFlowModelingStage) curStage).getModel();
-		notifyStageChangeListeners();
 	}
 
 	public boolean connectEdge(mxCell edge, mxCell src, mxCell dst) {
@@ -466,7 +460,7 @@
 		if (!stageChanged) return false;
 		
 		boolean isConnected = ((DataFlowModelingStage) curStage).connectEdge(edge, src, dst);
-		notifyStageChangeListeners();
+
 		return isConnected;
 	}
 
@@ -476,7 +470,6 @@
 		if (!stageChanged) return;
 		
 		((DataFlowModelingStage) curStage).delete();
-		notifyStageChangeListeners();
 	}
 
 	public static class SrcDstAttribute extends EdgeAttribute {
diff --git a/AlgebraicDataflowArchitectureModel/src/application/views/NavigationWindow.java b/AlgebraicDataflowArchitectureModel/src/application/views/NavigationWindow.java
index de83e6d..ca47c26 100644
--- a/AlgebraicDataflowArchitectureModel/src/application/views/NavigationWindow.java
+++ b/AlgebraicDataflowArchitectureModel/src/application/views/NavigationWindow.java
@@ -22,6 +22,7 @@
 	private JToggleButton dataFlowModelingButton;
 	private JToggleButton pushPullSelectionButton;
 	private JToggleButton controlFlowDelegationButton;
+	private boolean forbidReentry = false;
 	
 	public NavigationWindow(ApplicationWindow owner, Editor editor) {
 		super(owner);
@@ -52,6 +53,7 @@
 
 	@Override
 	public void stageChanged(Stage newStage) {
+		if (forbidReentry) return;
 		if (newStage instanceof DataFlowModelingStage) {
 			dataFlowModelingButton.setSelected(true);
 			if (editor.canChange(Editor.STAGE_PUSH_PULL_SELECTION)) {
@@ -94,7 +96,9 @@
 	private class DataFlowModelingButtonListener implements ActionListener {
 		@Override
 		public void actionPerformed(ActionEvent e) {
+			forbidReentry = true;
 			editor.changeStage(Editor.STAGE_DATA_FLOW_MODELING);
+			forbidReentry = false;
 			if (editor.canChange(Editor.STAGE_PUSH_PULL_SELECTION)) {
 				pushPullSelectionButton.setEnabled(true);
 			} else {
@@ -111,7 +115,9 @@
 	private class PushPullSelectionButtonListener implements ActionListener {
 		@Override
 		public void actionPerformed(ActionEvent e) {
+			forbidReentry = true;
 			editor.changeStage(Editor.STAGE_PUSH_PULL_SELECTION);
+			forbidReentry = false;
 			if (editor.canChange(Editor.STAGE_DATA_FLOW_MODELING)) {
 				dataFlowModelingButton.setEnabled(true);
 			} else {
@@ -128,7 +134,9 @@
 	private class ControlFlowDelegationButtonListener implements ActionListener {
 		@Override
 		public void actionPerformed(ActionEvent e) {
+			forbidReentry = true;
 			editor.changeStage(Editor.STAGE_CONTROL_FLOW_DELEGATION);
+			forbidReentry = false;
 			if (editor.canChange(Editor.STAGE_DATA_FLOW_MODELING)) {
 				dataFlowModelingButton.setEnabled(true);
 			} else {