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Bug 361772

Summary:	[FastViews][Presentation] PartPlaceholder cannot be cast to org.eclipse.ui.internal.ContainerPlaceholder
Product:	[Eclipse Project] Platform	Reporter:	Daniel Stein <daniel.stein>
Component:	UI	Assignee:	Platform UI Triaged <platform-ui-triaged>
Status:	CLOSED WONTFIX	QA Contact:
Severity:	normal
Priority:	P3	CC:	emoffatt, remy.suen
Version:	3.7.1
Target Milestone:	---
Hardware:	PC
OS:	Windows XP
Whiteboard:	stalebug

Description Daniel Stein

2011-10-24 03:37:09 EDT

Build Identifier: 20110916-0149

It seems that a user of my RCP was able to drag a PlaceHolder into a FastViewContainer. How is this posible. 
Trace: 

java.lang.ClassCastException: org.eclipse.ui.internal.PartPlaceholder cannot be cast to org.eclipse.ui.internal.ContainerPlaceholder
	at org.eclipse.ui.internal.FastViewDnDHandler$ViewDropTarget.adoptRef(FastViewDnDHandler.java:103)
	at org.eclipse.ui.internal.FastViewDnDHandler$ViewDropTarget.drop(FastViewDnDHandler.java:94)
	at org.eclipse.ui.internal.dnd.DragUtil.performDrag(DragUtil.java:134)
	at org.eclipse.ui.internal.PartStack.paneDragStart(PartStack.java:1720)
	at org.eclipse.ui.internal.PartStack.dragStart(PartStack.java:1688)
	at org.eclipse.ui.internal.PartStack.access$0(PartStack.java:1685)
	at org.eclipse.ui.internal.PartStack$1.dragStart(PartStack.java:129)
	at org.eclipse.ui.internal.presentations.util.TabbedStackPresentation$1.handleEvent(TabbedStackPresentation.java:112)
	at org.eclipse.ui.internal.presentations.util.AbstractTabFolder.fireEvent(AbstractTabFolder.java:269)
	at org.eclipse.ui.internal.presentations.util.AbstractTabFolder.fireEvent(AbstractTabFolder.java:282)
	at org.eclipse.ui.internal.presentations.util.AbstractTabFolder.handleDragStarted(AbstractTabFolder.java:366)
	at org.eclipse.ui.internal.presentations.util.AbstractTabFolder$2.handleEvent(AbstractTabFolder.java:67)
	at org.eclipse.ui.presentations.PresentationUtil.handleMouseMove(PresentationUtil.java:110)
	at org.eclipse.ui.presentations.PresentationUtil.access$4(PresentationUtil.java:95)
	at org.eclipse.ui.presentations.PresentationUtil$2.handleEvent(PresentationUtil.java:63)
	at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1053)
	at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:4165)
	at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3754)
	at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:2696)
	at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:2660)
	at org.eclipse.ui.internal.Workbench.access$4(Workbench.java:2494)
	at org.eclipse.ui.internal.Workbench$7.run(Workbench.java:674)
	at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332)
	at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:667)
	at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149)




Reproducible: Sometimes

Comment 1 Eric Moffatt

2011-10-25 15:43:30 EDT

Sounds odd to me as well, do you have a presentation that allows placeholders to be visible on the screen ? I'm wondering how they *started* the drag...

Comment 2 Daniel Stein

2011-10-26 01:42:30 EDT

(In reply to comment #1)
> do you have a presentation that allows placeholders
> to be visible on the screen ?
No I define my layout in a Perspective  (extention point: org.eclipse.ui.perspective)

> I'm wondering how they *started* the drag...
Me too.

Comment 3 Lars Vogel

2019-11-14 03:29:25 EST

This bug hasn't had any activity in quite some time. Maybe the problem got resolved, was a duplicate of something else, or became less pressing for some reason - or maybe it's still relevant but just hasn't been looked at yet.

If you have further information on the current state of the bug, please add it. The information can be, for example, that the problem still occurs, that you still want the feature, that more information is needed, or that the bug is (for whatever reason) no longer relevant.

If the bug is still relevant, please remove the "stalebug" whiteboard tag.