Fixed crash when components change after HighLevelStateShell is closed

diff --git a/net.mograsim.logic.model/src/net/mograsim/logic/model/LogicUICanvas.java b/net.mograsim.logic.model/src/net/mograsim/logic/model/LogicUICanvas.java
index 11e4634..51778c1 100644 (file)
--- a/net.mograsim.logic.model/src/net/mograsim/logic/model/LogicUICanvas.java
+++ b/net.mograsim.logic.model/src/net/mograsim/logic/model/LogicUICanvas.java
@@ -2,6 +2,7 @@ package net.mograsim.logic.model;
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.function.Consumer;
 
 import org.eclipse.swt.SWT;
 import org.eclipse.swt.graphics.Color;
@@ -83,8 +84,14 @@ public class LogicUICanvas extends ZoomableCanvas
                Combo componentSelector = new Combo(debugShell, SWT.DROP_DOWN | SWT.READ_ONLY);
                componentSelector.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, false));
                List<GUIComponent> componentsByItemIndex = new ArrayList<>();
-               model.addComponentAddedListener(c -> recalculateComponentSelector(componentsByItemIndex, componentSelector, model));
-               model.addComponentRemovedListener(c -> recalculateComponentSelector(componentsByItemIndex, componentSelector, model));
+               Consumer<? super GUIComponent> compsChanged = c -> recalculateComponentSelector(componentsByItemIndex, componentSelector, model);
+               model.addComponentAddedListener(compsChanged);
+               model.addComponentRemovedListener(compsChanged);
+               debugShell.addListener(SWT.Dispose, e ->
+               {
+                       model.removeComponentAddedListener(compsChanged);
+                       model.removeComponentRemovedListener(compsChanged);
+               });
                recalculateComponentSelector(componentsByItemIndex, componentSelector, model);
                new Label(debugShell, SWT.NONE).setText("Target state ID: ");
                Text stateIDText = new Text(debugShell, SWT.SINGLE | SWT.LEAD | SWT.BORDER);