#495 – Binding to a Visibility Property Without Using a Value Converter

You can use a value converter to convert a string value to a value of type System.Windows.Visibility, allowing data binding to a Visibility property.  You can also just set a Visibility property directly to a string, avoiding the need for a value converter.

In the example below, we bind to the Content property of a ComboBoxItem, which we access through the SelectedValue property of a ComboBox.  Since Content contains a string, the binding to Visibility works without a conversion.

    <StackPanel>
        <StackPanel Orientation="Horizontal" Margin="10">
            <Label Content="Snoopy" Margin="3" Background="BurlyWood"/>
            <Label Content="Waldo" Margin="3" Background="Thistle"
                   Visibility="{Binding ElementName=cboVisibility, Path=SelectedValue.Content}"/>
            <Label Content="Dagwood" Margin="3" Background="LightGreen"/>
        </StackPanel>
        <ComboBox Name="cboVisibility" HorizontalAlignment="Center" SelectedIndex="0">
            <ComboBox.Items>
                <ComboBoxItem Content="Visible"/>
                <ComboBoxItem Content="Collapsed"/>
                <ComboBoxItem Content="Hidden"/>
            </ComboBox.Items>
        </ComboBox>
        <Label Content="Select visibility of middle Label" HorizontalAlignment="Center"/>
    </StackPanel>

#494 – Using a Value Converter to Bind to a Visibility Property

You can bind the Visibility property of a control to a data item whose type is System.Windows.Visibility.  You can also bind to an item whose type is string, provided that the string values returned represent one of the enumerated values from the Visibility type.

The example below shows how to use a value converter to convert from the SelectedValue of a ComboBox (a ComboBoxItem) to the Visibility type.

        <StackPanel Orientation="Horizontal" Margin="10">
            <Label Content="Snoopy" Margin="3" Background="BurlyWood"/>
            <Label Content="Waldo" Margin="3" Background="Thistle"
                   Visibility="{Binding ElementName=cboVisibility, Path=SelectedValue, Converter={StaticResource cboVisibilityConverter}}"/>
            <Label Content="Dagwood" Margin="3" Background="LightGreen"/>
        </StackPanel>
        <ComboBox Name="cboVisibility" HorizontalAlignment="Center" SelectedIndex="0">
            <ComboBox.Items>
                <ComboBoxItem Content="Visible"/>
                <ComboBoxItem Content="Collapsed"/>
                <ComboBoxItem Content="Hidden"/>
            </ComboBox.Items>
        </ComboBox>

Code for IValueConverter.Convert:

        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
        {
            Visibility visibility = Visibility.Visible;

            try
            {
                if (value != null)
                {
                    ComboBoxItem item = (ComboBoxItem)value;
                    visibility = (Visibility)Enum.Parse(typeof(Visibility), (string)item.Content, false);
                }
            }
            catch { }

            return visibility;
        }