Popup box - focus element when opened

[cocofaivre]

Hi everyone,

I try to focus a textbox in popup when it opens. The goal is when user opens popup, he can edit a textbox immediately.

The result displays cursor in textbox but I can't enter value in textbox:

My xaml code is:

<materialDesign:PopupBox x:Name="pop_up_search" HorizontalAlignment="Right" VerticalAlignment="Top" 
                         PlacementMode="LeftAndAlignTopEdges" StaysOpen="True" Opened="PopupBox_Opened">
    <materialDesign:PopupBox.ToggleContent>
        <materialDesign:PackIcon Kind="Magnify" Width="40" Height="40" Foreground="White"></materialDesign:PackIcon>
    </materialDesign:PopupBox.ToggleContent>
    <Grid x:Name="grid_pop_up" Height="100" Width="300" Loaded="grid_pop_up_Loaded">
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="auto"></ColumnDefinition>
            <ColumnDefinition Width="1*"></ColumnDefinition>
        </Grid.ColumnDefinitions>
        <TextBlock Text="Search: " Style="{StaticResource TextBlockInfo}" VerticalAlignment="Center"></TextBlock>
        <TextBox Grid.Column="1" x:Name="input_search_n" Style="{StaticResource TextBoxTool}"></TextBox>
    </Grid>
</materialDesign:PopupBox>

I try two events : Grid.Loaded and PopupBox.Opened. The result is same.

private void PopupBox_Opened(object sender, RoutedEventArgs e)
{
    FocusManager.SetFocusedElement(grid_pop_up, input_search_n);
    //FocusManager.SetFocusedElement(this, input_search_n);
}

private void grid_pop_up_Loaded(object sender, RoutedEventArgs e)
{
    FocusManager.SetFocusedElement(grid_pop_up, input_search_n);
}

Someone have an idea ?

Thank's for your help.

[nicolaihenriksen]

@cocofaivre Perhaps not the cleanest of solutions, but this could be an option. Simply pushing a call to Focus() onto the back of the UI message pump:

private void PopupBox_Opened(object sender, RoutedEventArgs e)
{
    Dispatcher.BeginInvoke(() => { input_search_n.Focus(); });
}

[cocofaivre]

I test that and it's works.. . lol :)

Thank's

private void PopupBox_Opened(object sender, RoutedEventArgs e)
{
    Dispatcher.BeginInvoke((Action)(() =>{input_search_n.Focus(); }));
}