[Solved] Cegui v0-8: The Element object referenced by '__auto_titlebar__' is not attached to Element at

[Bertram]

Hey there,

I'm posting this time because of a bug encountered on OpenDungeons when using the v0-8 branch of the bitbucket repository:
Here is the whole issue: https://github.com/OpenDungeons/OpenDungeons/issues/965

Basically, our code is working fine when using cegui 0.8.4, but when using cegui v0-8 from bitbucket and trying to load a FrameWindow , the following error is displayed:

Code: Select all

(Error) CEGUI::UnknownObjectException in function 'CEGUI::NamedElement* CEGUI::NamedElement::getChildElement(const CEGUI::String&) const' (~/src/cegui/cegui/src/NamedElement.cpp:150) : The Element object referenced by '__auto_titlebar__' is not attached to Element at 'SettingsWindow'.


Link to the full cegui.log: https://gist.github.com/t4im/834e72d0112c6351a0e0

Also, here is our lnf config for framewindows:

Code: Select all

   <WidgetLook name="OD/FrameWindow">
        <PropertyLinkDefinition initialValue="FFFFFFFF" name="CaptionColour" targetProperty="CaptionColour" widget="__auto_titlebar__" />
        <PropertyLinkDefinition name="TitlebarFont" targetProperty="Font" widget="__auto_titlebar__" />
        <Property name="NSSizingCursorImage" value="OpenDungeonsSkin/MouseNoSoCursor" />
        <Property name="EWSizingCursorImage" value="OpenDungeonsSkin/MouseEsWeCursor" />
        <Property name="NWSESizingCursorImage" value="OpenDungeonsSkin/MouseNwSeCursor" />
        <Property name="NESWSizingCursorImage" value="OpenDungeonsSkin/MouseNeSwCursor" />
        <NamedArea name="ClientWithTitleWithFrame">
            <Area />

        </NamedArea>
        <NamedArea name="ClientWithTitleNoFrame">
            <Area>
                <Dim type="LeftEdge"><AbsoluteDim value="0" /></Dim>
                <Dim type="Width"><UnifiedDim scale="1" type="Width" /></Dim>
                <Dim type="BottomEdge"><WidgetDim dimension="BottomEdge" /></Dim>
            </Area>
        </NamedArea>
        <NamedArea name="ClientNoTitleWithFrame">
            <Area>
                <Dim type="LeftEdge"><ImageDim dimension="Width" name="OpenDungeonsSkin/WindowTopLeft" /></Dim>
                <Dim type="TopEdge"><ImageDim dimension="Height" name="OpenDungeonsSkin/WindowTopEdge" /></Dim>
                <Dim type="RightEdge">
                    <OperatorDim op="Subtract">
                        <UnifiedDim scale="1" type="RightEdge" />
                        <ImageDim dimension="Width" name="OpenDungeonsSkin/WindowTopRight" />
                    </OperatorDim>
                </Dim>
                <Dim type="BottomEdge">
                    <OperatorDim op="Subtract">
                        <UnifiedDim scale="1" type="BottomEdge" />
                        <ImageDim dimension="Height" name="OpenDungeonsSkin/WindowBottomEdge" />
                    </OperatorDim>
                </Dim>
            </Area>
        </NamedArea>
        <NamedArea name="ClientNoTitleNoFrame">
            <Area>
                <Dim type="LeftEdge"><AbsoluteDim value="0" /></Dim>
                <Dim type="TopEdge"><AbsoluteDim value="0" /></Dim>
                <Dim type="Width"><UnifiedDim scale="1" type="Width" /></Dim>
                <Dim type="Height"><UnifiedDim scale="1" type="Height" /></Dim>
            </Area>
        </NamedArea>
        <Child nameSuffix="__auto_titlebar__" type="OD/Titlebar">
            <Area>
                <Dim type="LeftEdge"><AbsoluteDim value="0" /></Dim>
                <Dim type="TopEdge"><AbsoluteDim value="0" /></Dim>
                <Dim type="Width"><UnifiedDim scale="1" type="Width" /></Dim>
                <Dim type="Height">
                    <FontDim padding="12" type="LineSpacing" />
                </Dim>
            </Area>
            <Property name="AlwaysOnTop" value="False" />
            <Property name="WantsMultiClickEvents" value="False" />
        </Child>
        <Child nameSuffix="__auto_closebutton__" type="OD/SystemButton">
            <Area>
                <Dim type="LeftEdge">
                    <OperatorDim op="Subtract"><UnifiedDim scale="1" type="LeftEdge" />
                        <OperatorDim op="Add">
                            <ImageDim dimension="Width" name="OpenDungeonsSkin/SysAreaRight" />
                            <ImageDim dimension="Width" name="OpenDungeonsSkin/SysAreaMiddle" />
                        </OperatorDim>
                    </OperatorDim>
                </Dim>
                <Dim type="TopEdge">
                    <OperatorDim op="Multiply">
                        <AbsoluteDim value="0.5" />
                        <OperatorDim op="Subtract">
                            <WidgetDim dimension="Height" widget="__auto_titlebar__" />
                            <ImageDim dimension="Width" name="OpenDungeonsSkin/CloseButtonNormal" />
                        </OperatorDim>
                    </OperatorDim>
                </Dim>
                <Dim type="Width"><ImageDim dimension="Width" name="OpenDungeonsSkin/CloseButtonNormal" /></Dim>
                <Dim type="Height"><ImageDim dimension="Width" name="OpenDungeonsSkin/CloseButtonNormal" /></Dim>
            </Area>
            <Property name="AlwaysOnTop" value="True" />
            <Property name="NormalImage" value="OpenDungeonsSkin/CloseButtonNormal" />
            <Property name="HoverImage" value="OpenDungeonsSkin/CloseButtonHover" />
            <Property name="PushedImage" value="OpenDungeonsSkin/CloseButtonPressed" />
        </Child>
        <ImagerySection name="withtitle_frame">
            <FrameComponent>
                <Area>
                    <Dim type="LeftEdge"><AbsoluteDim value="0" /></Dim>
                    <Dim type="TopEdge">
                        <WidgetDim dimension="BottomEdge" widget="__auto_titlebar__" />
                        <UnifiedDim offset="0" type="Height" />
                    </Dim>
                    <Dim type="Width"><UnifiedDim scale="1" type="Width" /></Dim>
                    <Dim type="BottomEdge"><UnifiedDim scale="1" type="BottomEdge" /></Dim>
                </Area>
                <Image component="TopEdge" name="OpenDungeonsSkin/WindowTopEdge" />
                <Image component="TopLeftCorner" name="OpenDungeonsSkin/WindowTopLeft" />
                <Image component="TopRightCorner" name="OpenDungeonsSkin/WindowTopRight" />
                <Image component="BottomLeftCorner" name="OpenDungeonsSkin/WindowBottomLeft" />
                <Image component="BottomRightCorner" name="OpenDungeonsSkin/WindowBottomRight" />
                <Image component="LeftEdge" name="OpenDungeonsSkin/WindowLeftEdge" />
                <Image component="RightEdge" name="OpenDungeonsSkin/WindowRightEdge" />
                <Image component="BottomEdge" name="OpenDungeonsSkin/WindowBottomEdge" />
                <Image component="Background" name="OpenDungeonsSkin/ClientBrush" />
                <VertFormat type="Tiled" />
                <HorzFormat type="Tiled" />
            </FrameComponent>
        </ImagerySection>
        <ImagerySection name="notitle_frame">
            <FrameComponent>
                <Area>
                    <Dim type="LeftEdge"><AbsoluteDim value="0" /></Dim>
                    <Dim type="TopEdge"><AbsoluteDim value="0" /></Dim>
                    <Dim type="Width"><UnifiedDim scale="1" type="Width" /></Dim>
                    <Dim type="Height"><UnifiedDim scale="1" type="Height" /></Dim>
                </Area>
                <Image component="TopLeftCorner" name="OpenDungeonsSkin/WindowTopLeft" />
                <Image component="TopRightCorner" name="OpenDungeonsSkin/WindowTopRight" />
                <Image component="BottomLeftCorner" name="OpenDungeonsSkin/WindowBottomLeft" />
                <Image component="BottomRightCorner" name="OpenDungeonsSkin/WindowBottomRight" />
                <Image component="LeftEdge" name="OpenDungeonsSkin/WindowLeftEdge" />
                <Image component="RightEdge" name="OpenDungeonsSkin/WindowRightEdge" />
                <Image component="BottomEdge" name="OpenDungeonsSkin/WindowBottomEdge" />
                <Image component="Background" name="OpenDungeonsSkin/ClientBrush" />
                <VertFormat type="Tiled" />
                <HorzFormat type="Tiled" />
            </FrameComponent>
        </ImagerySection>
        <ImagerySection name="withtitle_noframe_client_area">
            <ImageryComponent>
                <Area>
                    <Dim type="LeftEdge"><AbsoluteDim value="0" /></Dim>
                    <Dim type="TopEdge">
                        <WidgetDim dimension="BottomEdge" widget="__auto_titlebar__" />
                        <UnifiedDim offset="0" type="Height" />
                    </Dim>
                    <Dim type="Width"><UnifiedDim scale="1" type="Width" /></Dim>
                    <Dim type="BottomEdge"><UnifiedDim scale="1" type="BottomEdge" /></Dim>
                </Area>
                <Image name="OpenDungeonsSkin/ClientBrush" />
                <VertFormat type="Tiled" />
                <HorzFormat type="Tiled" />
            </ImageryComponent>
        </ImagerySection>
        <ImagerySection name="notitle_noframe_client_area">
            <ImageryComponent>
                <Area>
                    <Dim type="LeftEdge"><AbsoluteDim value="0" /></Dim>
                    <Dim type="TopEdge"><AbsoluteDim value="0" /></Dim>
                    <Dim type="Width"><UnifiedDim scale="1" type="Width" /></Dim>
                    <Dim type="Height"><UnifiedDim scale="1" type="Height" /></Dim>
                </Area>
                <Image name="OpenDungeonsSkin/ClientBrush" />
                <VertFormat type="Tiled" />
                <HorzFormat type="Tiled" />
            </ImageryComponent>
        </ImagerySection>
        <StateImagery name="ActiveWithTitleWithFrame">
            <Layer>
                <Section section="withtitle_frame" />
            </Layer>
        </StateImagery>
        <StateImagery name="InactiveWithTitleWithFrame">
            <Layer>
                <Section section="withtitle_frame" />
            </Layer>
        </StateImagery>
        <StateImagery name="DisabledWithTitleWithFrame">
            <Layer>
                <Section section="withtitle_frame">
                    <Colours bottomLeft="FF7F7F7F" bottomRight="FF7F7F7F" topLeft="FF7F7F7F" topRight="FF7F7F7F" />
                </Section>
            </Layer>
        </StateImagery>
        <StateImagery name="ActiveWithTitleNoFrame">
            <Layer>
                <Section section="withtitle_noframe_client_area" />
            </Layer>
        </StateImagery>
        <StateImagery name="InactiveWithTitleNoFrame">
            <Layer>
                <Section section="withtitle_noframe_client_area" />
            </Layer>
        </StateImagery>
        <StateImagery name="DisabledWithTitleNoFrame">
            <Layer>
                <Section section="withtitle_noframe_client_area">
                    <Colours bottomLeft="FF7F7F7F" bottomRight="FF7F7F7F" topLeft="FF7F7F7F" topRight="FF7F7F7F" />
                </Section>
            </Layer>
        </StateImagery>
        <StateImagery name="ActiveNoTitleWithFrame">
            <Layer>
                <Section section="notitle_frame" />
            </Layer>
        </StateImagery>
        <StateImagery name="InactiveNoTitleWithFrame">
            <Layer>
                <Section section="notitle_frame" />
            </Layer>
        </StateImagery>
        <StateImagery name="DisabledNoTitleWithFrame">
            <Layer>
                <Section section="notitle_frame">
                    <Colours bottomLeft="FF7F7F7F" bottomRight="FF7F7F7F" topLeft="FF7F7F7F" topRight="FF7F7F7F" />
                </Section>
            </Layer>
        </StateImagery>
        <StateImagery name="ActiveNoTitleNoFrame">
            <Layer>
                <Section section="notitle_noframe_client_area" />
            </Layer>
        </StateImagery>
        <StateImagery name="InactiveNoTitleNoFrame">
            <Layer>
                <Section section="notitle_noframe_client_area" />
            </Layer>
        </StateImagery>
        <StateImagery name="DisabledNoTitleNoFrame">
            <Layer>
                <Section section="notitle_noframe_client_area">
                    <Colours bottomLeft="FF7F7F7F" bottomRight="FF7F7F7F" topLeft="FF7F7F7F" topRight="FF7F7F7F" />
                </Section>
            </Layer>
        </StateImagery>
    </WidgetLook>


Any ideas of what I could be doing wrong with the development codebase of 0-8?

Best regards,

Bertram

[Ident]

I thought that was fixed already - it could be related to the order of initialisation of child widgets.

[hwoarangmy]

Hello,

I have been working on this issue for the OpenDungeons project and seen something weird in the CEGUI code. Basically, it seems the __auto_titlebar__ from the FrameWindow is removed twice when the widget is destroyed. Thus, the second time, an exception is thrown.
I've checked with CEGUI 0.8.5 official.

From what I've seen, the bug would come from:
Window.cpp - void Window::removeChild_impl(Element* element)
We call Element::removeChild_impl(wnd); (line 1245)
=> That removes the __auto_titlebar__ widget.
Then, we call wnd->deactivate(); (line 1261)
=> It tries to remove the __auto_titlebar__ widget again and throws an exception as it is not found

The relevant backtrace of first removal (doesn't crash) is

Code: Select all

#0  0x750d9f8e in msvcrt!memmove () from C:\Windows\syswow64\msvcrt.dll
#1  0x63c65b14 in std::__copy_move<false, true, std::random_access_iterator_tag>::__copy_m<CEGUI::Element*> (__first=0x21fe2f24, __last=0x21fe2f34, __result=0x21fe2f20) at C:/mingw-w64/i686-5.1.0-posix-dwarf-rt_v4-rev0/mingw32/i686-w64-mingw32/include/c++/bits/stl_algobase.h:382
#2  0x63caf283 in std::__copy_move_a<false, CEGUI::Element**, CEGUI::Element**> (__first=0x21fe2f24, __last=0x21fe2f34, __result=0x21fe2f20) at C:/mingw-w64/i686-5.1.0-posix-dwarf-rt_v4-rev0/mingw32/i686-w64-mingw32/include/c++/bits/stl_algobase.h:400
#3  0x63cb12cd in std::__copy_move_a2<false, __gnu_cxx::__normal_iterator<CEGUI::Element**, std::vector<CEGUI::Element*, std::allocator<CEGUI::Element*> > >, __gnu_cxx::__normal_iterator<CEGUI::Element**, std::vector<CEGUI::Element*, std::allocator<CEGUI::Element*> > > > (__first=..., __last=..., __result=...) at C:/mingw-w64/i686-5.1.0-posix-dwarf-rt_v4-rev0/mingw32/i686-w64-mingw32/include/c++/bits/stl_algobase.h:436
#4  0x63cb7efc in std::copy<__gnu_cxx::__normal_iterator<CEGUI::Element**, std::vector<CEGUI::Element*, std::allocator<CEGUI::Element*> > >, __gnu_cxx::__normal_iterator<CEGUI::Element**, std::vector<CEGUI::Element*, std::allocator<CEGUI::Element*> > > > (__first=..., __last=..., __result=...) at C:/mingw-w64/i686-5.1.0-posix-dwarf-rt_v4-rev0/mingw32/i686-w64-mingw32/include/c++/bits/stl_algobase.h:470
#5  0x63c84e11 in std::vector<CEGUI::Element*, std::allocator<CEGUI::Element*> >::_M_erase (this=0x21fb08e4, __position=...) at C:/mingw-w64/i686-5.1.0-posix-dwarf-rt_v4-rev0/mingw32/i686-w64-mingw32/include/c++/bits/vector.tcc:145
#6  0x63c84c99 in std::vector<CEGUI::Element*, std::allocator<CEGUI::Element*> >::erase (this=0x21fb08e4, __position=...) at C:/mingw-w64/i686-5.1.0-posix-dwarf-rt_v4-rev0/mingw32/i686-w64-mingw32/include/c++/bits/stl_vector.h:1150
#7  0x63b17645 in CEGUI::Element::removeChild_impl (this=0x21fb08a8, element=0x21fba338) at C:\dev\cegui-0.8.5\cegui\src\Element.cpp:581
#8  0x63b427fb in CEGUI::Window::removeChild_impl (this=0x21fb08a8, element=0x21fba338) at C:\dev\cegui-0.8.5\cegui\src\Window.cpp:1245
#9  0x63b157fd in CEGUI::Element::removeChild (this=0x21fb08a8, element=0x21fba338) at C:\dev\cegui-0.8.5\cegui\src\Element.cpp:374
#10 0x63b465e5 in CEGUI::Window::destroy (this=0x21fba338) at C:\dev\cegui-0.8.5\cegui\src\Window.cpp:1770
#11 0x63b50aeb in CEGUI::WindowManager::destroyWindow (this=0x1c891ce8, window=0x21fba338) at C:\dev\cegui-0.8.5\cegui\src\WindowManager.cpp:214
#12 0x63b418c8 in CEGUI::Window::destroyChild (this=0x21fb08a8, wnd=0x21fba338) at C:\dev\cegui-0.8.5\cegui\src\Window.cpp:844
#13 0x63bad5bb in CEGUI::WidgetComponent::cleanup (this=0x1c8cf360, parent=...) at C:\dev\cegui-0.8.5\cegui\src\falagard\WidgetComponent.cpp:110
#14 0x63bafe35 in CEGUI::WidgetLookFeel::cleanUpWidget (this=0x1c8c8810, widget=...) at C:\dev\cegui-0.8.5\cegui\src\falagard\WidgetLookFeel.cpp:321
#15 0x63b46573 in CEGUI::Window::destroy (this=0x21fb08a8) at C:\dev\cegui-0.8.5\cegui\src\Window.cpp:1756
#16 0x63b50aeb in CEGUI::WindowManager::destroyWindow (this=0x1c891ce8, window=0x21fb08a8) at C:\dev\cegui-0.8.5\cegui\src\WindowManager.cpp:214


The relevant backtrace of the second call (the one crashing) is:

Code: Select all

#0  0x63bc7114 in __cxa_throw () from C:\devMinGW\cegui-0.8.5-ogre1.10\inst\bin\libCEGUIBase-0_d.dll
#1  0x63b2a604 in CEGUI::NamedElement::getChildElement (this=0x21fb08a8, name_path=...) at C:\dev\cegui-0.8.5\cegui\src\NamedElement.cpp:148
#2  0x63c5573d in CEGUI::Window::getChild (this=0x21fb08a8, name_path=...) at C:/dev/cegui-0.8.5/cegui/include/CEGUI/Window.h:753
#3  0x63b630a2 in CEGUI::FrameWindow::getTitlebar (this=0x21fb08a8) at C:\dev\cegui-0.8.5\cegui\src\widgets\FrameWindow.cpp:913
#4  0x63b618a2 in CEGUI::FrameWindow::onDeactivated (this=0x21fb08a8, e=...) at C:\dev\cegui-0.8.5\cegui\src\widgets\FrameWindow.cpp:725
#5  0x63b415af in CEGUI::Window::deactivate (this=0x21fb08a8) at C:\dev\cegui-0.8.5\cegui\src\Window.cpp:773
#6  0x63b42889 in CEGUI::Window::removeChild_impl (this=0x20bac250, element=0x21fb08a8) at C:\dev\cegui-0.8.5\cegui\src\Window.cpp:1261
#7  0x63b157fd in CEGUI::Element::removeChild (this=0x20bac250, element=0x21fb08a8) at C:\dev\cegui-0.8.5\cegui\src\Element.cpp:374
#8  0x63b465e5 in CEGUI::Window::destroy (this=0x21fb08a8) at C:\dev\cegui-0.8.5\cegui\src\Window.cpp:1770
#9  0x63b50aeb in CEGUI::WindowManager::destroyWindow (this=0x1c891ce8, window=0x21fb08a8) at C:\dev\cegui-0.8.5\cegui\src\WindowManager.cpp:214


I've looked the differences between CEGUI 0.8.4 and CEGUI 0.8.5 and seen that the call to wnd->deactivate(); has been added. However, that bug seems too systematic to not have been seen. I've tried to copy the FrameWindow look n feel from CEGUI 0.8.5 into OpenDungeons to check if the definition of the object was the reason of the bug but I got the same crash.

The definition of our FrameWindow is here:
https://github.com/OpenDungeons/OpenDun ... nfeel#L907

To delete it, we call:

Code: Select all

CEGUI::WindowManager* wmgr = CEGUI::WindowManager::getSingletonPtr();
wmgr->destroyWindow(mSettingsWindow);

Could you please confirm if we correctly use the FrameWindow and, if yes, if you see a workaround ?
If you want, I can create a patch to fix that but do you see something better than checking if the widget exists before removing it in widgets\FrameWindow.cpp:725 ?

[Ident]

Do you have a simple repro for this? Is destroying the FrameWindow all it takes?

[YaronCT]

Ident:

Do you have a simple repro for this? Is destroying the FrameWindow all it takes?

Yes, it does.

What happens is that when "destroy" is called on the frame window, we first (in "Window::destroy") "cleanup" the widget:

Code: Select all

    // clean up looknfeel related things
    if (!d_lookName.empty())
    {
        d_windowRenderer->onLookNFeelUnassigned();
        WidgetLookManager::getSingleton().getWidgetLook(d_lookName).
            cleanUpWidget(*this);
    }

which (perhaps among other things) removes its children (like the title bar). Then, later on in "Window::destroy", we remove the frame window from its parent:

Code: Select all

    // double check we are detached from parent
    if (d_parent)
        d_parent->removeChild(this);

which calls "invalidate" on the frame window, which calls "FrameWindow::onDeactivated", which calls "getTitlebar()". But the titlebar is no longer a child of the frame window, so we throw an exception. It seems to me like the order is ilogical: in "Window::destroy", removing the window from its parent should come b4 cleaning up the widget. I've tested it and it seems to solve the problem.

[Ident]

Apparently this is not triggered on deinitalisation of the SampleBrowser, which is the reason this went unnoticed by me. I am looking into your suggestion, yaronct

[Ident]

Yaron's suggestion seems totally logical to me and works: Fixed in v0-8 https://bitbucket.org/cegui/cegui/commi ... 1eca12aba5

We probably have to make a new Release now soon.

[YaronCT]

We probably have to make a new Release now soon.

Yeah, I thought so too.. and fire our whole QA team.

Perhaps we should release immediately? If we decide it's worth releasing, what's the point of waiting?

[Ident]

@hwoarangmy can you confirm it is fixed in v0-8 ? If so we will rush a new Release.

[hwoarangmy]

Thanks for the fix. I will test ASAP and tell you if it fixes our bug.

[hwoarangmy]

I've just tried and confirm it works. Thanks for the fix ^^
I will wait for the new version to come out.

[Ident]

Thanks for confirming it, i will try to get the new Release out soon

See also https://bitbucket.org/cegui/cegui/issue ... en-element