LastChildFill in DockPanel not working for height

Question

In a UserControl I have:

<Grid>
        <DockPanel Grid.Column="0"
                   LastChildFill="True">
            <Label x:Name="ProductName"
                   HorizontalAlignment="Stretch"
                   DockPanel.Dock="Top"
                   Background="Red"
                   Height="60" />
            <Label x:Name="Versie"
                   HorizontalAlignment="Stretch"
                   DockPanel.Dock="Top"
                   Background="Green"
                   Height="20" />
            <Label x:Name="Copyright"
                   HorizontalAlignment="Stretch"
                   DockPanel.Dock="Top"
                   Background="Blue"
                   Height="20" />
            <Label x:Name="Company"
                   HorizontalAlignment="Stretch"
                   DockPanel.Dock="Top"
                   Background="Yellow"
                   Height="20" />
            <Label x:Name="Omschrijving"
                   HorizontalAlignment="Stretch"
                   **--> Answer: add this: VerticalAlignment="Stretch"**
                   Background="Tomato"/>
        </DockPanel>
    </Grid>

I expected that the last label would fill the available vertical space in the dockpanel/grid, because of LastChildFill="True". Its height however is a default 'auto' of 10, it doesn't fill.
The last label does not respond to DockPanel.Dock which I suppose is ok and a result of LastChildFill="True".

What can I do to make the heigth fill the remaining height?

Adi Lester Adi Lester · Accepted Answer · 2013-10-30T21:44:16

The last label fills to fit the remaining space in the DockPanel; however, the problem is that your DockPanel currently only takes up the space required by its children.

If the main grid has space to offer, setting VerticalAlignment="Stretch" in your DockPanel will stretch the DockPanel to take up all the vertical space it can, and the last label will do that in turn.

LastChildFill in DockPanel not working for height

1 Answers