Question

Here is what I am trying to do.

Toggle button 1 (editNameOpen)

• When checked, show the popup content
• The only way to close it is from another toggle button inside of the popup (editNameClose)

Toggle button 2 (editNameClose)

• this inside of the popup
• when IsChecked, close the popup AND make editNameOpen closed

Here is some xaml I’m using to try and work out the kinks. Problems / questions so far:

1. My MultiBinding is wrong and throws a runtime error “Cannot set MultiBinding because MultiValueConverter must be specified.” What would the MultiValueConverter be converting in this case?
2. How would I close the 1st toggle button when the 2nd is checked?

Cheers,
Berryl

<ToggleButton x:Name="editNameOpen" Style="{StaticResource EditToggleButtonStyle}" Grid.Column="1" Grid.Row="0"/>

<Popup x:Name="popupNameEditingControl"
       PlacementTarget="{Binding ElementName=editeditNameOpenName}"
       PopupAnimation="Slide"
       StaysOpen="False"    ** shoulf this be true?
       MinWidth="50">

    ** open and stay open while until editNameClose is checked
    <Popup.IsOpen>
        <MultiBinding >
            <Binding Mode="OneWay" ElementName="editNameOpen" Path="IsChecked"/>
            <Binding Mode="OneWay" ElementName="editNameClose" Path="IsChecked" Converter="{StaticResource invertBoolConv}"/>
        </MultiBinding>
    </Popup.IsOpen>

    ** how do we reset editNameOpen to be NOT IsChecked when editNameClose is checked?
    ** how do we reset editNameClose to be NOT IsChecked and then reset editNameClose to also be not checked when this opens again?
    <StackPanel Orientation="Horizontal" Background="{DynamicResource {x:Static SystemColors.ControlBrushKey}}">
        <Label Content="Hello Wolrd!"/>
        <ToggleButton x:Name="editNameClose" Content="X"/>
    </StackPanel>
</Popup>

Answer 1

Personally I would bind Popup.IsOpen and both ToggleButtons to a single boolean property in the DataContext

So when the first ToggleButton gets checked, it sets the boolean value to true, which makes Popup.IsOpen evaluate as true and open the Popup

The second ToggleButton will probably need to use a Converter to reverse the boolean property, so it shows as unchecked when IsOpen = true, and checking it will make IsOpen = false, which will automatically close the Popup and uncheck the first ToggleButton

As for the error you’re getting, a MultiBinding expects a Converter of type IMultiValueConverter because you cannot bind one property to two separate values. You need a converter to convert those values into a single value you can use.

If you really want to do it this way instead of using a property in the DataContext, try binding the IsOpen property of the Popup and the IsChecked properties of your ToggleButtons all together.

<Popup x:Name="popupNameEditingControl"
       IsOpen="{Binding IsChecked, ElementName=editNameOpen, Mode=TwoWay}"
       ... >
    ...
    <ToggleButton x:Name="editNameClose" Content="X"
                  IsChecked="{Binding IsChecked, ElementName=editNameOpen, 
                      Converter={StaticResource ReverseBooleanConverter}, Mode=TwoWay}" />
    ...
</Popup>