CODEWITHSUNDEEP
wpfdata-binding
OwenP
OwenP

Reputation: 25408

What's the difference between these two bindings?

Long ago, I looked at this MSDN walkthrough. It implements a color editor, and the tooltip uses the color's name like "Red" or "Blue".

Today, I'm implementing a ListBox that is similar; it displays a box with the color and the name of the color next to it. Except in my application, all of the color names display as the hex values like #FFFF0000 and #FF0000FF. Why?

Here's the ColorsList class used in both projects:

public ColorsList()
{
    Type type = typeof(Colors);
    foreach (PropertyInfo propertyInfo in type.GetProperties(BindingFlags.Public | BindingFlags.Static))
    {
        if (propertyInfo.PropertyType == typeof(Color))
        {
            Add((Color)propertyInfo.GetValue(null, null));
        }
    }
}

This XAML snippet makes the tooltip use the color name in the MSDN project (you can see the rest of the code in the walkthrough):

<ItemsControl.ItemTemplate>
    <DataTemplate>
        <Button Tag="{Binding}" Command="{x:Static PropertyEditing:PropertyValueEditorCommands.ShowInlineEditor}">
            <Button.Template>
                <ControlTemplate>
                    <Border Width="30" Height="30" BorderBrush="Black" BorderThickness="1" CornerRadius="5">
                        <Rectangle Width="22" Height="22" ToolTip="{Binding}">
                            <Rectangle.Fill>
                                <SolidColorBrush Color="{Binding}"/>
                            </Rectangle.Fill>
                        </Rectangle>
                    </Border>
                </ControlTemplate>
            </Button.Template>
        </Button>
    </DataTemplate>
</ItemsControl.ItemTemplate>

Here's my XAML that produces the hex codes:

<ListBox x:Name="lstColors" Grid.Row="1" ItemsSource="{StaticResource colors}">
    <ListBox.ItemTemplate>
        <DataTemplate>
            <StackPanel Orientation="Horizontal">
                <Rectangle Stroke="Black"
                           StrokeThickness="3"
                           Width="24"
                           Height="24"
                           RadiusX="5"
                           RadiusY="5">
                    <Rectangle.Fill>
                        <SolidColorBrush Color="{Binding}" />
                    </Rectangle.Fill>
                </Rectangle>
                <TextBlock Text="{Binding}" />
            </StackPanel>
        </DataTemplate>
    </ListBox.ItemTemplate>
</ListBox>

It looks the same to me; what's the difference?

Upvotes: 0

Views: 414

Answers (2)

OwenP
OwenP

Reputation: 25408

It turns out design-time is different from run-time. The MSDN example is used as an extended property editor. I took a friend's advice and tried exposing it as a runtime control, and magically it's getting hash names for colors instead of friendly names. Neat.

Upvotes: 0

irobot
irobot

Reputation: 1024

Not exactly an answer to your question, more of an observation:

If you change ColorsList to inherit from ObservableCollection<string> instead of ObservableCollection<Color> and modify the following line:

Add((Color)propertyInfo.GetValue(null, null));

to

Add(propertyInfo.Name);

your code will work as you want it to work. Instead of converting Color to color name, this is going the other way around - using the built-in conversion from color name to Color.

As a side note, I tried the XAML code from the MSDN sample (only the part you're citing) but the tooltips display color codes and not color names.

Upvotes: 1

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