组合框TouchDown和MouseDown不会触发

Question

I am using WPF and has a combobox which is editable.

I added TouchDown and MouseDown event handler, but it never fire up when I touch on the combobox.

What I plan to do is to have the drop down listed down when I touch or click on the combobox.

How can I do it?

<ComboBox Name="cbProductList" Height="45" Width="260" IsEditable="True"
        ItemsSource="{Binding Source={StaticResource ProductsSource}}" 
        DisplayMemberPath="Name" SelectedValuePath="ProductId"
        SelectedIndex="0" FontSize="23" FontFamily="Segoe WP"
        VerticalAlignment="Stretch" FlowDirection="LeftToRight"
        HorizontalAlignment="Left" HorizontalContentAlignment="Left"
        SelectionChanged="cbProductList_SelectionChanged" />

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Found this: How do I show the drop-down in a combobox in WPF?

But this event fire when something is type. I want it to fire when the combobox is clicked.

Answer 1

You need to add the property AutoPostBack="true" :

<ComboBox Name="cbProductList" Height="45" Width="260" IsEditable="True"
        ItemsSource="{Binding Source={StaticResource ProductsSource}}" 
        DisplayMemberPath="Name" SelectedValuePath="ProductId"
        SelectedIndex="0" FontSize="23" FontFamily="Segoe WP"
        VerticalAlignment="Stretch" FlowDirection="LeftToRight"
        HorizontalAlignment="Left" HorizontalContentAlignment="Left"
        SelectionChanged="cbProductList_SelectionChanged"
        autopostback="true" />