Grid in a combo box [modified]

Lutoslaw

Hello again! I have searched for it but couldn't find an apropriate solution. I have a list of objects, and I want to arrange them in rows, but still allowing user to select any individual item. For example:

list = { a1, a2,a3,b1,b2,b3}

In a combobox I would like to see:

[ ]V
a1 a2 a3
b1 b2 b3

Items in a combobox are enumeration members and value of a combobox should be bound. User can select any value from the list. Moreover, items a2,b2,c2,... (that is, when index%3==1) should appear in bold (extra feature). I have tried to set a List<List<MyClass>> as a datasource, but in that case user would be able to set a whole row and not individual items. Such behaviour is unacceptable. How to accomplish this? Thanks in advance,

Greetings - Jacek

modified on Sunday, July 31, 2011 6:56 PM

teejayem · modified on Sunday, July 31, 2011 6:56 PM

From MSDN[^] - A ListBoxItem is a ContentControl, which means that it can contain a single object of any type (such as a string, an image, or a panel). This means you can directly add any type of content you wish (like a grid).

        Grid grid = new Grid();
        grid.Children.Add(new TextBlock { Text = "Hello"});

        listBox.Items.Add(grid);

Or you can use a grid in your ItemTemplate

        listBox.ItemsSource = new MyClass\[\] {
            new MyClass { Property1 = "a1", Property2 = "a2", Property3 = "a3"},
            new MyClass { Property1 = "b1", Property2 = "b2", Property3 = "b3"},
            new MyClass { Property1 = "c1", Property2 = "c2", Property3 = "c3"},
        };

and the FontWeightConverter

public class FontWeightConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        String item = value as String;
        if (item == null) return FontWeights.Normal;

        int index = int.Parse(item.Substring(1, 1));

        return index % 3 == 1 ? Fon

Lutoslaw

Thanks for your answer! Unfortunately, I don't see how user could select, let say, "a3" in a grid without selecting "a1" and "a2". The list of possible values is flat, and the selection is bound to a single property. User has to choose a single item. Arranging items in a grid is a layout/GUI issue and does not reflect application logic. Less important: let's say that ther are n columns in a grid. The solution which you have kindly provided fixes n=3. Not so bad since the number of columns will be fixed, but IMHO it is risky and not easily scalable.

Greetings - Jacek

SledgeHammer01

I'd pass on this implementation. Too much hard coding of everything.

SledgeHammer01

Actually, a much simpler implementation would be to just swap out the item panel for a WrapPanel. Then you could select individual items... Simple as 1-2-3...

Lutoslaw

This is what I needed! Thanks very much! You have a knowledge of the framework. In this specific scenario, the exact solution is:

which gives exactly 5 items in a row, as requested.

Greetings - Jacek

SledgeHammer01

You're welcome. BTW... forgot to mention the bold thing... you should use the ListBox AlternationCount for the bold feature.

Lutoslaw

OK I will try it.

Greetings - Jacek