passing the current Window as a CommandParameter

Question

how can I pass the window I am currently on as a parameter to a command?

I like to do this in XAML-markup:

<Button Command="CommandGetsCalled" CommandParameter="-this?-" />

Gratin

Why? There is no "this" notation in XAML as far as I know. Besides, this in this case would probably be the button. What are you trying to do? – Liles

with -this- I meant the containing Window object. I write it in the title and in in the text, that I want to pass the window. As the answers of Rachel and Daniel Pratt show, its clear enough ;) – Gratin

Answer 1

There are two ways I can of think to do this: Give the window a name (via a x:Name attribute on the Window tag, and then construct a binding like this (assumes the name of the window is 'ThisWindow'):

<Button Command="CommandGetsCalled" CommandParameter="{Binding ElementName=ThisWindow}" />

For something more general (doesn't rely on giving the current Window a name), the binding can be constructed like this:

<Button Command="CommandGetsCalled" CommandParameter="{Binding RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type Window}}}" /> 

Ionian

Can you please show me how this could look like in the viewmodel? – Funest

Answer 2

You could try binding to a RelativeSource

If you want to pass the Button as a parameter:

<Button Command="CommandGetsCalled" 
        CommandParameter="{Binding RelativeSource={RelativeSource Self}}" />

If you want to pass the Window as a parameter:

<Button Command="CommandGetsCalled" 
        CommandParameter="{Binding RelativeSource={
             RelativeSource AncestorType={x:Type Window}}}" />

Runny

Thank you Rachel. I looked at your and Daniel Pratt's solutions. Actually they are quite similar. But I'll mark his as answer, because I like the idea of accessing the Window via its name. – Gratin

I'm getting Specified Visual is already a child of another Visual or the root of a CompositionTarget. when I try to use the Button as a parameter example. any ideas? – Batchelor

found out it's because I was trying to .Dump() the button in the canExecute via LinqPad which would wpf display it – Batchelor

Answer 3

In my situation none of the provided answers worked.

This worked for me:

<window x:Name="myWindow">
 <Button Command="Command" CommandParameter={x:Reference Name=myWindow}/>
</window>

Ostrich