WPF

ABitSmart wrote:

It's by design that no parameters are passed to it.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Collections.ObjectModel;
using System.Windows.Controls;
using System.Windows;

namespace SampleWpfApplication
{
  public class WordManager
  {
    public string Text { get; set; }
  }

  public class Words : ObservableCollection<WordManager>
  {
  }

  public class WordTemplateSelector : DataTemplateSelector
  {
    public DataTemplate NormalWordTemplate { get; set; }
    public DataTemplate RedWordTemplate { get; set; }

    public override DataTemplate SelectTemplate(object item, DependencyObject container)
    {
      WordManager word = item as WordManager;
      if (word.Text == "Howdy")
      {
        return RedWordTemplate;
      }
      else
      {
        return NormalWordTemplate;
      }
    }
  }
}

<Window x:Class="SampleWpfApplication.Window1"
  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="clr-namespace:SampleWpfApplication"
  Title="Window1" Height="300" Width="300">
  <Window.Resources>
    <DataTemplate x:Key="NormalWords">
      <Grid>
        <TextBlock Text="{Binding Path=Text}" Foreground="Brown"/>
      </Grid>
    </DataTemplate>

    <DataTemplate x:Key="RedWords">
      <TextBlock Text="{Binding Path=Text}" FontWeight="Bold" Foreground="Red"/>
    </DataTemplate>
    
    <local:Words x:Key="Words" />
    <local:WordTemplateSelector 
      x:Key="TemplateSelector" 
      NormalWordTemplate="{StaticResource NormalWords}"
      RedWordTemplate="{StaticResource RedWords}" />
  </Window.Resources>

  <StackPanel>
    <ListBox x:Name="myList" 
         ItemsSource="{Binding Mode=Default, Source={StaticResource Words}}" 
         ItemTemplateSelector="{StaticResource TemplateSelector}"
         x:FieldModifier="private"></ListBox>
    <TextBox x:Name="myText" x:FieldModifier="private" Width="30" />
    <Button Content="Click" Click="Button_Click" />
  </StackPanel>
</Window>

private void Button_Click(object sender, RoutedEventArgs e)
{
  if (!string.IsNullOrEmpty(myText.Text))
  {
    Words words = this.Resources["Words"] as Words;
    if (words != null)
    {
        words.Add(new WordManager{Text=myText.Text});
    }
  }
}

namespace AnagramsWPF
{

    public class WordItem
    {
        public string Text  {  get; set; } 
        public bool Used { get; set; }

        public WordItem(string text)
        {
            Text      = text;
            Used      = false;
        }

	public override string ToString()
        {
            return Text;
        }
    }


    public class WordTypeTemplateSelector : DataTemplateSelector
    {
        public DataTemplate UnusedWordTemplate { get; set; }
        public DataTemplate UsedWordTemplate { get; set; }

        public override DataTemplate SelectTemplate(object item, DependencyObject container)
        {
            WordItem wordItem = item as WordItem;
            DataTemplate template = null;
            if (wordItem.Used)
            {
                template = UsedWordTemplate;
            }
            else
            {
                template = UnusedWordTemplate;
            }
            return template;
        }
    }
}

<Window.Resources>
    <DataTemplate x:Key="unusedWord">
        <Grid>
            <TextBlock Text="{Binding Path=Text}" Foreground="DarkGray" />
        </Grid>
    </DataTemplate>
    <DataTemplate x:Key="usedWord">
        <Grid>
            <TextBlock Text="{Binding Path=Texe}" Foreground="Red" FontStyle="Italic" />
        </Grid>
    </DataTemplate>
    <local:WordTypeTemplateSelector
        x:Key="wordTypeTemplateSelector"
        UsedWordTemplate="{StaticResource usedwordTemplate}"
        UnusedWordTemplate="{StaticResource unusedwordTemplate}" />
</Window.Resources>

xmlns:local="clr-namespace:AnagramsWPF"