Question

I have a 2nd stackpanel that appears like a drawer, shown below

 ______               ______ _____
|      |             |      |     |
| main |     ->      | main | 2nd |
|______|             |______|_____|
                              -->

I have both expand and collapse animations for the drawer. They are bound to a boolean that I update in code.

Everything works fine, except when I initially start my application, the collapse animation gets fired because the initial value is false. Is there a way to bind something without it triggering upon binding?

Here is what is looks like in my xaml, where I am using a DataTrigger bound to the boolen thats in my code:

        <StackPanel x:Name="expandMe" Width="0" Orientation="Vertical" >
            <StackPanel.Style>
                <Style>
                    <Style.Triggers>
                        <DataTrigger Binding="{Binding ExpandBoolean}" Value="False">
                            .......

Answer 1

I don’t see the Setter in your style to make sure that the StackPanel loads collapsed. I think that will do it.

<StackPanel x:Name="expandMe" Width="0" Orientation="Vertical" >
        <StackPanel.Style>
            <Style>
                <Setter Property="StackPanel.Visibility" Value "Collapsed"/>
                <Style.Triggers>
                    <DataTrigger Binding="{Binding ExpandBoolean}" Value="False">