How do I make an item in a toolbar fill all available space in WPF

Question

I'm trying to make an item on ToolBar (specifically a Label, TextBlock, or a TextBox) That will fill all available horizontal space. I've gotten the ToolBar itself to stretch out by taking it out of its ToolBarTray, but I can't figure out how to make items stretch.

I tried setting Width to Percenatage or Star values, but it doesn't accept that. Setting Horizontal(Content)Alignment to Stretch in various places seems to have no effect either.

Answer 1

Unfortunately it looks like the default ControlTemplate for ToolBar doesn't use an ItemsPresenter, it uses a ToolBarPanel, so setting ToolBar.ItemsPanel won't have any effect.

ToolBarPanel inherits from StackPanel. By default its Orientation is bound to the parent ToolBar.Orientation, but you can override this and set its Orientation to Vertical with a Style and this will allow items to stretch horizontally:

<DockPanel>
    <ToolBar DockPanel.Dock="Top">
        <ToolBar.Resources>
            <Style TargetType="{x:Type ToolBarPanel}">
                <Setter Property="Orientation" Value="Vertical"/>
            </Style>
        </ToolBar.Resources>
        <ComboBox HorizontalAlignment="Stretch" SelectedIndex="0">
            <ComboBoxItem>A B C</ComboBoxItem>
            <ComboBoxItem>1 2 3</ComboBoxItem>
            <ComboBoxItem>Do Re Mi</ComboBoxItem>
        </ComboBox>
    </ToolBar>
    <Border Margin="10" BorderBrush="Yellow" BorderThickness="3"/>
</DockPanel>

You can then use a Grid or something in place of the ComboBox above if you want multiple items on a line.

Answer 2

Try putting a horizontal StackPanel in the ToolBar and then the element you want inside of that StackPanel.

Answer 3

Have you tried wrapping your item in a Grid, not in a StackPanel?

Answer 4

You need a special custom panel like auto stretched stack panel, and replace the toolbarpanel. Check this out you can find one panel there http://blendables.com/products/productsLayoutmix.aspx

Answer 5

I've had this same problem for a while, and there is very little help available online.

Since it doesn't sound like you need all the extra functionality of a Toolbar (collapsible/movable trays), why not just use a Top-docked Grid, and tweak the background a little to make it look like a standard toolbar?