Rhonda Tipton's WebLog

I attended the July D2 SIG Meeting this passed Tuesday.  Claudio Lassala was speaking on the topic of Data Binding in WPF.  Pretty good turnout of 30-35 people, especially since this is a fairly new group.

Claudio’s Information

• Blog: http://ClaudioLassala.spaces.live.com
• Email: Claudio@eps-software.com
• Twitter: http://Twitter.com/claudiolassala

High-level Presentation Summary

WPF – Windows Presentation Foundation – WikiPedia defines a WPF as graphical subsystem for rendering user interfaces in Windows-based applications.

XAML – Extensible Application Markup Language – The declarative language behind WPF

The simple concept of data binding is relating two objects and saying when one changes, so does the other.

Objects involved in Data Binding

• Target – TextBox, ComboBox,etc
• Source – Customer object

Binding Modes in WPF

• OneWay – reads the information from the source and populates the target TextBox.
• TwoWay – reads the information from the source and populates the target TextBox, but if the TextBox is changed, it updates the source Customer Object. This needs notification through a DependencyObject or INotifyPropertyChanged.
• OneWayToSource – sends data from the target to the source.

Types of Binding

• XAML Binding
• Programmatic Binding

Bindings can be removed using BindingOperations.ClearBinding() method

Relative Sources

• Self, TemplatedParent, FindAncestor, PreviousData
• Value Converters can convert values during the process of binding.
• Data Validation
• Data Templates

Some of the examples Claudio went over included

• Binding an image control to a byte array
• ListBox
• Validation Rules
• Simple Binding from Blend
• TwoWay Notification
• Rating to Color Converter
• XML Data Provider

Presentation Slides and Demo Code

Claudio does a great job of showing you how you should not code something then following by how you should.

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Until next time…

I attended the inaugural meeting of the D2 SIG last night and I have to say it was a pretty good turnout for a first meeting.  I counted about 40 people in attendance. 

The D2 (Developers 2 Designers) Special Interest Group is being put on by EPS Software and Torque FKM.  It will always be on the first Tuesday of each month at the Microsoft Houston offices.  The plan is for the meeting to start around 6:15 with a 30 minute tip/trick presentation and then a break and the main presentation will start at 7:00 and go to 8:30 or so. Sounds like a great plan and I look forward to future meetings.

Markus Egger gave a great overview presentation on WPF, Silverlight and Surface.  Some of the high points are below.

• The User Interface Revolution
• Technologies involved: Silverlight, WPF, ASP.NET (Web forms, AJAX, MVC), MS Surface
• Visual Studio and Expression Blend are used for the design of WPF applications
• Why new UI technologies – limitations of older technologies like GDI
• XAML – Declarative language for WPF interface layout
• Silverlight is basically WPF for the web
• Silverlight vs WPF – Silverlight is cross-platform

Markus also gave an overview of Surface and showed a couple of quick videos showing how it works. 

• Microsoft Surface
• Microsoft Surface – Parody

In closing, it was a successful meeting and has great promise of becoming a great addition to the existing groups here in Houston.

I received great news via e-mail of the new Houston-Area D2 Special Interest Group.  The D2 SIG is geared toward Siverlight and WPF designers/developers.  The information for the first meeting is below as well as a link to the future website.

When:   First Tuesday of Each Month 6:00 – 8:00 PM (First meeting is Thursday, November 6, due to Election Day)
Where:   Microsoft-Houston Offices (2000 West Sam Houston Parkway)
This special interest group (SIG) is a community effort open to all interested participants. Each month, a different presenter from various organizations will present to interested attendees. The group is dedicated to exploring modern user experiences (UX) which are part computer programming and part artistic design. While traditionally there has been little overlap in the two disciplines, users now expect a good experience with a professional look. Covered topics will range from development in Silverlight, WPF and related technologies such as Microsoft Surface to design of rich interactive experience for graphical designers. The group strives to provide a good balance of content that appeals to both developers and designers.
The inaugural meeting, to be held on Nov. 6th, 2008 introduces the SIG and the covered topics and technologies in general, before proceeding into this month’s presentation delivered by industry renowned expert, author, speaker, MVP, President of EPS Software Corp., and Publisher of CoDe Magazine, Markus Egger. Markus’ presentation will include the following topics:

• Introduction to Silverlight ans WPF (Windows)
• Creating a Silverlight Application
• Silverlight and WPF news from PDC!
• A first look at Microsoft Surface

RSVP Requested
Attendance of the SIG meetings is free. To allow us to plan the meetings better and to judge interest ahead of time, we ask people to RSVP here. (Signup through VPF Conversion is temporary and will be replaced in the future with www.d2sig.org.)

Questions?
Phone: 832-717-4445 x 32
E-Mail: info@d2sig.org

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Always learning.

XAML stands for Extensible Application Markup Language and is used extensively with Window Presentation Foundation (WPF) and Windows Workflow Foundation (WF).  Lester Lobo has created a great tool for previewing XAML code called XamlPadX.  I have not played with it too much, but what I have seen so far I like.  If you are working with XAML and don’t have the money to spend on Expression Blend, I recommend giving this tool a try.

It is easy to install.  Simply take some XAML code and paste it in the application.  You get immediate feedback.  Very nice.

I finally got around to installing Visual Studio 2008 this weekend. The first thing I thought I would try to learn something about is Windows Presentation Foundation (WPF). WPF is a graphical subsystem feature of the .NET 3.0 framework that provides a clear separation between UI and Business logic. The mark up language used in WPF is called Extensible Application Markup Language (XAML). XAML looks like any other markup language like HTML and XML.

Below is a sample form built in WPF.

Create new project

Solution Explorer

XAML Designer

Form in Runtime

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XAML Listing

<Window x:Class="FirstWpf.Window1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="Calculate Max Heart Rate" Height="181" Width="370" Background="LemonChiffon">
    <Grid Height="141" Width="339">
        <Button Margin="89,0,92,13" Name="button1" Click="button1_Click"
             Height="23"
             VerticalAlignment="Bottom"
             FontWeight="Bold"
             Foreground="DarkGreen">Click Me</Button>
        <TextBox Height="23" Margin="0,21,115,0" Name="textAge"
             VerticalAlignment="Top"
             HorizontalAlignment="Right" Width="36" />
        <Label Height="23" Margin="83,21,0,0" Name="label1"
             VerticalAlignment="Top" HorizontalAlignment="Left"
             Width="65" FontWeight="Bold"
             Foreground="DarkBlue">Enter Age</Label>
        <Label Margin="38,56,35,44" Name="labelHR" FontSize="9"
             ForceCursor="False" HorizontalContentAlignment="Center"></Label>
    </Grid>
</Window>

C# Code Behind

using System;
using System.Windows;

namespace FirstWpf
{
    public partial class Window1 : Window
    {
        public Window1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, RoutedEventArgs e)
        {
          try
          {
            int age = Int32.MinValue;
            int maxHr = 0;
            age = Int32.Parse(textAge.Text);
            maxHr = 220 - age;   labelHR.Content = "At the age of " + age.ToString() + " the Max HR should not rise above " + maxHr.ToString();
          }
          catch (Exception)
          {
            labelHR.Content = "Input is not valid";
            return;
          }
        }
    }
}

WPF/XAML is a feature rich and powerful programming model. In upcoming posts, I will go into deeper detail on some of the great features.

There are a plethora of internet resources for this interesting new technology. Below are just a few of them.

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Related Content
Windows Client.NET – Official MS Site
Josh Smith on WPF
Karl on WPF
WPF Wonderland
The WPF Blog
Learn WPF
Your XAML Information Page

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Happy programming!!!