Learning WPF

I'm trying to learn about Microsoft's Windows Presentation Foundation and I am going through the book "Applications = Code + Markup" by Charles Petzold. Usually for me to learn something like this, I would type out the code, which slows my reading down enough for me to ruminate on the code. But typing the code verbatim is sometimes a mind numbing exercise. So I decided to rewrite the C# code in F# instead. This helps learn F# while at the same time keeps me engaged in learning WPF. I'm going to start with Chapter 1 and work my way thru the chapters and see how far I get before I get tired of this exercise.

Why did I pick F# as the target programming language to translate the code to? Well, which the advent of multicore processors, functional programming languages seems naturally suited to the new hardware architectures. In addition, Wall Street Journal made a passing reference to F# in the article Behind Microsoft's Bid to Gain Cutting Edige. I figure if Wall Street Journal have an article about F#, it seems about time that F# will become mainstream. Having two F# books coming out also helps developers to start learning about this language by Microsoft.

Here are the F# versions of Charles Petzold's code for Chapter 1:

SayHello.cs

#light 
#I @"C:\Program Files\Reference Assemblies\Microsoft\Framework\v3.0"
#r @"WindowsBase.dll"
#r @"PresentationCore.dll"
#r @"PresentationFramework.dll"

open System
open System.Windows

(* From Chap 1 - SayHello.cs *)
let win = new Window()
win.Title <- "Say Hello"
win.Show()

#if COMPILED
[<STAThread()>]
do 
    let app =  new Application() in
    app.Run() |> ignore
#endif



HandleAnEvent.cs

#light 
#I @"C:\Program Files\Reference Assemblies\Microsoft\Framework\v3.0"
#r @"WindowsBase.dll"
#r @"PresentationCore.dll"
#r @"PresentationFramework.dll"

open System
open System.Windows
open System.Windows.Input

(* From Chap 1 - HandleAnEvent.cs *)
let WindowOnMouseDown sender (args:MouseButtonEventArgs) =
   let win = unbox<Window> sender
   let str = string.Format("Window clicked with {0} button at point ({1})",args.ChangedButton,args.GetPosition(win))
   MessageBox.Show(str)|>ignore

let win = new Window()
win.Title <- "Handle an Event"
win.add_MouseDown(new MouseButtonEventHandler(WindowOnMouseDown))


#if COMPILED
[<STAThread()>]
do 
    let app =  new Application() in
    app.Run(win) |> ignore
#endif


InheritTheApp.cs

#light 
#I @"C:\Program Files\Reference Assemblies\Microsoft\Framework\v3.0"
#r @"WindowsBase.dll"
#r @"PresentationCore.dll"
#r @"PresentationFramework.dll"

open System
open System.Windows
open System.Windows.Input

(* From Chap 1 - InheritTheApp.cs *)
type InheritTheApp = class
   inherit Application as base
   
   // No constructor
   new () as this = {}
   
   override this.OnStartup (args:StartupEventArgs) =
      base.OnStartup(args)
      let win = new Window()
      win.Title <- "Inherit the App"
      win.Show()
      
   override this.OnSessionEnding (args:SessionEndingCancelEventArgs) =
      base.OnSessionEnding(args)
      let result = MessageBox.Show("Do you want to save your data?", base.MainWindow.Title, MessageBoxButton.YesNoCancel, MessageBoxImage.Question, MessageBoxResult.Yes)
      args.Cancel <- (result = MessageBoxResult.Cancel)

end

#if COMPILED
[<STAThread()>]
do 
    let app =  new InheritTheApp() in
    app.Run() |> ignore
#endif


MyWindow.cs + MyApplication.cs +InheritAppAndWindowApp.cs

#light 
#I @"C:\Program Files\Reference Assemblies\Microsoft\Framework\v3.0"
#r @"WindowsBase.dll"
#r @"PresentationCore.dll"
#r @"PresentationFramework.dll"

open System
open System.Windows
open System.Windows.Input

(* From Chap 1 - MyWindow.cs *)
type MyWindow = class
   inherit Window as base
   
   new () as this = {} then
      this.Title <- "Inherit App & Window "

   override this.OnMouseDown (args:MouseButtonEventArgs) =
      base.OnMouseDown(args)
      
      let strMessage = string.Format("Window clicked with {0} button at point ({1})",args.ChangedButton,args.GetPosition(this))
      MessageBox.Show(strMessage,this.Title) |> ignore
end

(* From Chap 1 - MyApplication.cs *)
type MyApplication = class
   inherit Application as base
   
   // No constructor
   new () as this = {}
   
   override this.OnStartup (args:StartupEventArgs) =
      base.OnStartup(args)
      
      let win = new MyWindow()
      win.Show()      
end

(* From Chap 1 - InheritAppAndWindow.cs *)
#if COMPILED
[<STAThread()>]
do 
    let app =  new MyApplication() in
    app.Run() |> ignore
#endif



GrowAndShrink.cs

#light 
#I @"C:\Program Files\Reference Assemblies\Microsoft\Framework\v3.0"
#r @"WindowsBase.dll"
#r @"PresentationCore.dll"
#r @"PresentationFramework.dll"

open System
open System.Windows
open System.Windows.Input

(* From Chap 1 - GrowAndShrink.cs *)
type GrowAndShrink = class
   inherit Window as base
   
   new () as this = {} then
      this.Title <- "Grow & Shrink"
      this.WindowStartupLocation <- WindowStartupLocation.CenterScreen
      this.Width <- 192.0
      this.Height <- 192.0

   override this.OnKeyDown (args:KeyEventArgs) =
      base.OnKeyDown(args)      
      if (args.Key = Key.Up) then
         this.Left <- this.Left - 0.05 * this.Width
         this.Top <- this.Top - 0.05 * this.Height
         this.Width <- this.Width * 1.1
         this.Height <- this.Height * 1.1
      else if (args.Key = Key.Down) then
         this.Left <- this.Left + 0.05 * (this.Width/1.1)
         this.Top <- this.Top + 0.05 * (this.Height/1.1)
         this.Width <- this.Width/1.1
         this.Height <- this.Height /1.1
      
         
end


#if COMPILED
[<STAThread()>]
do 
    let app =  new Application() in
    app.Run(new GrowAndShrink()) |> ignore
#endif



TypeYourTitle.cs

#light 
#I @"C:\Program Files\Reference Assemblies\Microsoft\Framework\v3.0"
#r @"WindowsBase.dll"
#r @"PresentationCore.dll"
#r @"PresentationFramework.dll"

open System
open System.Windows
open System.Windows.Input

(* From Chap 1 - TypeYourTitle.cs *)
type TypeYourTitle = class
   inherit Window as base
   
   new () as this = {} 

   override this.OnTextInput (args:TextCompositionEventArgs) =
      base.OnTextInput(args)      
      if (args.Text = "\b" && this.Title.Length > 0) then
         this.Title <- this.Title.Substring(0,this.Title.Length -1)
      //  Change > operator to >= operator or what you type will not show up
      else if (this.Title.Length >= 0 && (not (Char.IsControl(String.get args.Text 0)) )) then
         this.Title <- this.Title + args.Text
      
         
end


#if COMPILED
[<STAThread()>]
do 
    let app =  new Application() in
    app.Run(new TypeYourTitle()) |> ignore
#endif