WPF/XAML Databinding Question

Question

Hello, I am writing an application in C#/WPF and am trying to figure out how to databind the width of the grids column definitions to a fraction of the screen width. Is this possible? Essentially I want something like this:

Grid = 2x2
Row 1 Height = 2/3 of screen height
Row 2 Height = 1/3 of screen height
Row 1 Width = 2/3 of screen width
Row 2 Width = 1/3 of screen width

I think that this correctly binds the full width to a column definition:

<ColumnDefinition Width="{Binding ElementName=Window1, Path=Width}"/>

but what I don't know how to do is perform an operation on the value it gets through the databinding... is this even possible? I feel like this is something I should be able to code into the XAML and not have to implement programmatically but I have little experience with UI design :( I would want something like:

<ColumnDefinition Width="{Binding ElementName=Window1, Path=Width} * 2 / 3"/>

but that is invalid

Should I just be writing a function to re-layout UI elements whenever the screen resizes? I feel like that is redundant... or is there some easy way of doing this that I don't know about? Any input welcome! Thanks!

Answer 1

It sounds like you just want to use star sizing:

<Grid>
    <Grid.RowDefinitions>
        <RowDefinition Height="2*"/>
        <RowDefinition Height="1*"/>
    </Grid.RowDefinitions>
    <Grid.ColumnDefinitions>
        <ColumnDefinition Width="2*"/>
        <ColumnDefinition Width="1*"/>
    </Grid.ColumnDefinitions>

This will always give the first row 2/3 of the height and the second row 1/3 of the height, and the first column 2/3 of the width and the second column 1/3 of the width. It will be based on the size of the Grid, but if the Grid is the only child of the Window then that will be the same as the size of the Window.