Skip to main content

C# Silverlight - Using a DataGridTemplateColumn [Beginner]


Whenever you pit designers against developers, it always seems to be the developer that loses. It's very rare that controls like the Silverlight DataGrid are left alone - designers want little tweaks and polish to increase the user experience. This tutorial is going to illustrate how to use one of the most flexible solutions to theming a DataGrid - the DataGridTemplateColumn.

We'll be touching very little on the basics of how to use the Silverlight DataGrid. If you're new to the control.

The first thing we're going to do is build a default DataGrid without any styling. I created a class to hold some information about the SOTC authors and bound a collection of those to my DataGrid.
[silverlight width="400" height="300" src="BasicDataGrid.xap"]
using System.Collections.Generic;
using System.Windows.Controls;

namespace DataGridStyling
{
  public partial class Page : UserControl
  {
    public Page()
    {
      InitializeComponent();

      // Create some authors.
      List<Author> authors = new List<Author>()
      {
        new Author() 
        { 
          Name = "Brandon", 
          Username = "The Reddest", 
          Language = "C#"
        },
        new Author() 
        { 
          Name = "Charlie", 
          Username = "The Fattest", 
          Language = "ActionScript"
        },
        new Author() 
        { 
          Name = "Richard", 
          Username = "The Hairiest", 
          Language = "PHP"
        },
        new Author() 
        { 
          Name = "Mike", 
          Username = "The Tallest", 
          Language = "JavaScript"
        }
      };

      // Set the items source on the DataGrid to the
      // collection of authors.
      _dataGrid.ItemsSource = authors;
    }
  }

  /// <summary>
  /// Class to hold some information about an 
  /// SOTC author.
  /// </summary>
  public class Author
  {
    public string Name { get; set; }
    public string Username { get; set; }
    public string Language { get; set; }
  }
}

<UserControl x:Class="DataGridStyling.Page"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:dg="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls.Data"
    Width="400" Height="300">
  <Grid x:Name="LayoutRoot" Background="White">
    <dg:DataGrid x:Name="_dataGrid" 
                 AutoGenerateColumns="False">
      <dg:DataGrid.Columns>
        <dg:DataGridTextColumn 
          Binding="{Binding Name}" 
          Header="Name" 
          Width="100" />
        <dg:DataGridTextColumn 
          Binding="{Binding Username}" 
          Header="Username" 
          Width="100" />
        <dg:DataGridTextColumn 
          Binding="{Binding Language}" 
          Header="Language" 
          Width="100" />
      </dg:DataGrid.Columns>
    </dg:DataGrid>
  </Grid>
</UserControl>
 
All right, now let's starting using the DataGridTemplateColumn. This column type gives us the ability to set the template for normal cells and cells that are in edit mode. Here's the same example as above except that uses this column type on the Name column.

[silverlight width="400" height="300" src="TemplateColumn.xap"]
<dg:DataGrid x:Name="_dataGrid" 
             AutoGenerateColumns="False">
  <dg:DataGrid.Columns>
    <dg:DataGridTemplateColumn 
      Header="Name" 
      Width="100">
      <dg:DataGridTemplateColumn.CellTemplate>
        <DataTemplate>
          <TextBlock Text="{Binding Name}" 
                   Foreground="Green" 
                   FontWeight="Bold"
                   VerticalAlignment="Center"/>
        </DataTemplate>
      </dg:DataGridTemplateColumn.CellTemplate>
      <dg:DataGridTemplateColumn.CellEditingTemplate>
        <DataTemplate>
          <TextBox Text="{Binding Name, Mode=TwoWay}" />
        </DataTemplate>
      </dg:DataGridTemplateColumn.CellEditingTemplate>
    </dg:DataGridTemplateColumn>
    <dg:DataGridTextColumn 
      Binding="{Binding Username}" 
      Header="Username" 
      Width="100" />
    <dg:DataGridTextColumn 
      Binding="{Binding Language}" 
      Header="Language" 
      Width="100" />
  </dg:DataGrid.Columns>
</dg:DataGrid>
 
So as you can see, we changed the cell to display bold green text when not in edit mode, and a simple TextBox when it is in edit mode. This is accomplished by using the CellTemplate and CellEditingTemplate properties on the DataGridTemplateColumn object. I had to explicitly set the BindingMode to TwoWay so text entered into the TextBox would be committed back to my Author object.

Here's a slightly more interesting example that builds on the previous one. Now, whenever edit mode is entered, a pencil icon will be displayed to the left of the edit field.

[silverlight width="400" height="300" src="Pencil.xap"]
<dg:DataGrid x:Name="_dataGrid" 
             AutoGenerateColumns="False">
  <dg:DataGrid.Columns>
    <dg:DataGridTemplateColumn 
      Header="Name" 
      Width="100">
      <dg:DataGridTemplateColumn.CellTemplate>
        <DataTemplate>
          <TextBlock Text="{Binding Name}" 
                   Foreground="Green" 
                   FontWeight="Bold"
                   VerticalAlignment="Center"/>
        </DataTemplate>
      </dg:DataGridTemplateColumn.CellTemplate>
      <dg:DataGridTemplateColumn.CellEditingTemplate>
        <DataTemplate>
          <Grid>
            <Grid.ColumnDefinitions>
              <ColumnDefinition Width="Auto" />
              <ColumnDefinition Width="*" />
            </Grid.ColumnDefinitions>
            <Image Source="pencil_icon.png" 
                   Grid.Column="0" />
            <TextBox Text="{Binding Name, Mode=TwoWay}" 
                     Grid.Column="1" />
          </Grid>
        </DataTemplate>
      </dg:DataGridTemplateColumn.CellEditingTemplate>
    </dg:DataGridTemplateColumn>
    <dg:DataGridTextColumn 
      Binding="{Binding Username}" 
      Header="Username" 
      Width="100" />
    <dg:DataGridTextColumn 
      Binding="{Binding Language}" 
      Header="Language" 
      Width="100" />
  </dg:DataGrid.Columns>
</dg:DataGrid>
 
All I had to do in order to use the pencil icon was add it to my project like you would any other existing item. By default the Build Action property on the image will be set to Resource, which is what you want. Now, in XAML, you can simply reference the image by name.

There are basically no limits to how you can display information within cells using this column type. The powerful templating system behind Silverlight and WPF makes doing stuff like this trivial whereas before it may not have even been possible to accomplish the same task. On that note, that wraps up this introduction to the DataGridTemplateColumn.

Comments

Popular posts from this blog

C# Snippet - Shuffling a Dictionary [Beginner]

Randomizing something can be a daunting task, especially with all the algorithms out there. However, sometimes you just need to shuffle things up, in a simple, yet effective manner. Today we are going to take a quick look at an easy and simple way to randomize a dictionary, which is most likely something that you may be using in a complex application. The tricky thing about ordering dictionaries is that...well they are not ordered to begin with. Typically they are a chaotic collection of key/value pairs. There is no first element or last element, just elements. This is why it is a little tricky to randomize them. Before we get started, we need to build a quick dictionary. For this tutorial, we will be doing an extremely simple string/int dictionary, but rest assured the steps we take can be used for any kind of dictionary you can come up with, no matter what object types you use. Dictionary < String , int > origin = new Dictionary < string , int >();

C# Snippet - The Many Uses Of The Using Keyword [Beginner]

What is the first thing that pops into your mind when you think of the using keyword for C#? Probably those lines that always appear at the top of C# code files - the lines that import types from other namespaces into your code. But while that is the most common use of the using keyword, it is not the only one. Today we are going to take a look at the different uses of the using keyword and what they are useful for. The Using Directive There are two main categories of use for the using keyword - as a "Using Directive" and as a "Using Statement". The lines at the top of a C# file are directives, but that is not the only place they can go. They can also go inside of a namespace block, but they have to be before any other elements declared in the namespace (i.e., you can't add a using statement after a class declaration). Namespace Importing This is by far the most common use of the keyword - it is rare that you see a C# file that does not h

C# WPF Printing Part 2 - Pagination [Intermediate]

About two weeks ago, we had a tutorial here at SOTC on the basics of printing in WPF . It covered the standard stuff, like popping the print dialog, and what you needed to do to print visuals (both created in XAML and on the fly). But really, that's barely scratching the surface - any decent printing system in pretty much any application needs to be able to do a lot more than that. So today, we are going to take one more baby step forward into the world of printing - we are going to take a look at pagination. The main class that we will need to do pagination is the DocumentPaginator . I mentioned this class very briefly in the previous tutorial, but only in the context of the printing methods on PrintDialog , PrintVisual (which we focused on last time) and PrintDocument (which we will be focusing on today). This PrintDocument function takes a DocumentPaginator to print - and this is why we need to create one. Unfortunately, making a DocumentPaginator is not as easy as