Question

I’m learning WPF and XAML. Here is my Form XAML code and the code for my class (ListboxMenuItem)

<Window x:Class="Bail.MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:src="clr-namespace:Bail"
    Title="MainWindow" Height="768" Width="1024" WindowStartupLocation="CenterScreen"
    Closing="Window_Closing" ResizeMode="NoResize">
    <Grid>
        <Grid.Resources> 
            <src:ListboxMenuItems x:Key="ListboxMenuItems"/>
        </Grid.Resources>
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="185" />
            <!-- Or Auto -->
            <ColumnDefinition Width="*" />
        </Grid.ColumnDefinitions>


        <ListBox Width="150" Margin="0,5,0,10" Grid.Column="0"
                 ItemsSource="{StaticResource ListboxMenuItems}">
            <ListBox.ItemTemplate>
                <DataTemplate>
                    <StackPanel Orientation="Horizontal">
                        <TextBlock Padding="5,0,5,0" Text="{Binding FirstName}" />
                        <TextBlock Text="{Binding LastName}" />
                        <TextBlock Text=", " />
                        <TextBlock Text="{Binding Address}" />
                    </StackPanel>
                </DataTemplate>
            </ListBox.ItemTemplate>            
        </ListBox>


        <Canvas Grid.Column="1" />
    </Grid>
</Window>

Here are the errors

---

after correcting the xmlns:src, I get the following
Warning:

Warning 1 ”src’ is an undeclared prefix. Line 8, position 14.’ XML is not valid. C:\Bail\Bail\Bail\MainWindow.xaml 8 14 Bail

The error refers to this line in the XAML (<src:ListboxMenuItems x:Key="ListboxMenuItems"/>)

ListBoxMenuItems is a class I created in C#.

Here;s the code to the class

//FileName: ListboxMenuItems.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Bail
{
    public class ListboxMenuItem
    {
        public String FirstName { get; set; }
        public String LastName { get; set; }
        public String Address { get; set; }

        public ListboxMenuItem(String firstName, String lastName, String address)
        {
            this.FirstName = firstName;
            this.LastName = lastName;
            this.Address = address;
        }
    }

    class ListboxMenuItems 
    { 
        List<ListboxMenuItem> Items { get; private set; } 
        public ListboxMenuItems() 
        { 
            Items = new List<ListboxMenuItem>(); 
            Items.Add(new ListboxMenuItem("Michael", "Anderberg", "12 North Third Street, Apartment 45")); 
            Items.Add(new ListboxMenuItem("Chris", "Ashton", "34 West Fifth Street, Apartment 67")); 
            Items.Add(new ListboxMenuItem("Cassie", "Hicks", "56 East Seventh Street, Apartment 89")); 
            Items.Add(new ListboxMenuItem("Guido", "Pica", "78 South Ninth Street, Apartment 10")); 
        } 
    }
}

Answer 1

your xmlns declaration at the top should include src:

xmlns:src=”clr-namespace:Bail”

Also, it looks like you’ll need to point your ItemsSource of your ListBox to Items within your class. I would suggest changing your class to just inherit from List and do away with the Items property:

class ListboxMenuItems : List<ListboxMenuItem>
{ 
    public ListboxMenuItems() 
    { 
        Add(new ListboxMenuItem("Michael", "Anderberg", "12 North Third Street, Apartment 45")); 
        Add(new ListboxMenuItem("Chris", "Ashton", "34 West Fifth Street, Apartment 67")); 
        Add(new ListboxMenuItem("Cassie", "Hicks", "56 East Seventh Street, Apartment 89")); 
        Add(new ListboxMenuItem("Guido", "Pica", "78 South Ninth Street, Apartment 10")); 
    } 
}

This should make it work.