Re: Binding IsChecked to AncestorType problem - WPF Discussion Boards

It's obviously an issue in your code. Have you installed a debug visualiser for bitmaps, and stepped through the code to see if they are black at the point of creation ? Or just added code to save them locally, pull them out of the DB and save them again, to see if the DB layer is the issue ? You have to cut the task into pieces to see which bit is breaking, and you need to seperate the images from your code for viewing, to make sure the viewer is not the issue, somehow.

Christian Graus

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"! i don't exactly like or do programming and it only gives me a headache." - spotted in VB forums.

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Christian,
Thanks for your reply...I don't think it's an issue with the viewer because it worked before...we had to change the code becasue we kept getting out of memory exceptions with the system.drawing stuff so we had to go to system.media.imaging (I think that's what it is) and we don't get the memory issue anymore. But the view worked perfectly for those images...I will look into the things you have suggested....

Thanks again

Chris

I would like to bind a MenuItem.IsChecked property to another using the FindAncestor approach. The problem I have is that the binding fails since the MenuItem is not in the same visual tree as it's ancestor due to (I think) the way it is created.

See http://munkiisoft.com/blog/archive/2007/02/01/binding-contextmenu-to-its-logical-parent.aspx as an example however my problem cannot be solved using this approach sine the ancestor is not the PlacementTarget.

Any ideas in how to how I can achieve this without I guess creating my own markup extension??????

Just in case the Xaml is shown below, nothing (I think again) is wrong here.

<MenuItem IsCheckable="True" x:Name="verticalRuler" Header="Vertical ruler" IsChecked="{Binding Path=VerticalRulerVisible, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type demo:demoBox}}, Mode=TwoWay}"/>

The error:
System.Windows.Data Error: 4 : Cannot find source for binding with reference 'RelativeSource FindAncestor, AncestorType='Demo.DemoBox', AncestorLevel='1''. BindingExpression:Path=VerticalRulerVisible; DataItem=null; target element is 'MenuItem' (Name=verticalRuler); target property is 'IsChecked' (type 'Boolean')

Thanks in advance. . .

You could always use the ElementName to achieve this effect instead,e.g.

<MenuItem IsCheckable="True" x:Name="verticalRuler" 
  Header="Vertical ruler" IsChecked="{Binding ElementName=... Path=VerticalRulerVisible}, Mode=TwoWay}"/>

"WPF has many lovers. It's a veritable porn star!" - Josh Smith

As Braveheart once said, "You can take our freedom but you'll never take our Hobnobs!" - Martin Hughes.

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Thanks for the reply but it's a little trickier than that since the source is not in the same template therefore I can't use ElementName, I have no choice but to use the FindAncestor approach which doesn't work.
Any other ideas?

Before we go any further with this, have you verified that the elements are in different visual trees? You can do this using snoop[^]. If you want to check hierarchies and bindings, this tool is invaluable.

"WPF has many lovers. It's a veritable porn star!" - Josh Smith

As Braveheart once said, "You can take our freedom but you'll never take our Hobnobs!" - Martin Hughes.

My blog | My articles | MoXAML PowerToys | Onyx

I presume the MenuItem belongs to a Context menu.

Bind using Context menu as Source and then use the PlacementTarget to reach the element you need.

Try something like this,

<Button Tag="{Binding RelativeSource={RelativeSource AncestorType={x:Type demo:demoBox}}}">
    <Button.ContextMenu>
        <ContextMenu>
            <MenuItem  IsChecked="{Binding Path=PlacementTarget.Tag.VerticalRulerVisible, RelativeSource={RelativeSource AncestorType={x:Type ContextMenu}}}"></MenuItem>
        </ContextMenu>
    </Button.ContextMenu>
</Button>

A bit smart indeed, nice one thanks I'll give it a try.

Hi,

I am working on WPF stack panel. In this I am dynamically adding images to the stack panel. While displaying the images i the stack panel all the images are displayed continously without any space between them. But I want to display the images with some space to separate them. That is I want to get some space between each item of the stack panel.

If anyone have any idea on this please reply me. Please note that I am adding children to the stack panel dynamically at run time.

Thanks in Advance

Set an appropriate Margin[^] to the image controls you add.

I have a Grid that is resizable via a storyboard animation. The user can turn off animations if he chooses to do so. If animations are turned off by the user, the grid is resized by directly manipulating the height property.

The problem: After using the animation to resize, the height property appears to reject manual setting of a given value. In other words, the following line is executed, but the math being performed is ignored:

myGrid.Height += someValue;

If I change the resizing mode to non-animated BEFORE resizing the grid, it works as expected. Once I resize with the storyboard, though, mannual resizing doesn't work.

I also tried changing the duration of the animator to 0.0, and that doesn't resize the grid either.

EDIT - I also tried changing the FillBehavior property.