Chapter 13. Graphical User Interface Concepts: Part 1

1
Chapter 13. Graphical User Interface Concepts
Part 1
2
Simple Windows Application

• In Visual Studio 2005, if you choose
• File-gtNew Project
• Windows Application
• The following will be generated for you
• Form1.cs
• Form1.Designer.cs
• Program.cs
• Lets look at them

3
(No Transcript)
4
Program.cs

• using System
• using System.Collections.Generic
• using System.Windows.Forms
• namespace SimpleApplication
• static class Program
• /// ltsummarygt
• /// The main entry point for the
  application.
• /// lt/summarygt
• STAThread
• static void Main()
• Application.EnableVisualStyles()
• Application.SetCompatibleTextRendering
  Default(false)
• Application.Run(new Form1())

What is this?
5
Form1.cs

• using System
• using System.Collections.Generic
• using System.ComponentModel
• using System.Data
• using System.Drawing
• using System.Text
• using System.Windows.Forms
• namespace SimpleApplication
• public partial class Form1 Form
• public Form1()
• InitializeComponent()

6
Form1.Designer.cs

• namespace SimpleApplication
• partial class Form1
• /// ltsummarygt
• /// Required designer variable.
• /// lt/summarygt
• private System.ComponentModel.IContainer
  components null
• /// ltsummarygt
• /// Clean up any resources being used.
• /// lt/summarygt
• /// ltparam name"disposing"gttrue if
  managed resources should be disposed otherwise,
  false.lt/paramgt
• protected override void Dispose(bool
  disposing)
• if (disposing (components !
  null))
• components.Dispose()

7
Application Class

• The System.Windows.Forms.Application class wraps
  the basic functionality to start a .NET
  application.
• This class has methods to start and stop
  applications and their threads, and to process
  Windows Messages
• DoEvents()
• Exit()
• ExitThread()
• Run()
• The class also has events and properties to
  synchronize execution.

8
Application Class

• Run static method begins running a standard
  application message loop on the current thread.
• Below is the overload list

9
Partial Class

• A partial class, or partial type, is a feature of
  C programming languages in which the declaration
  of a class or a struct or an interface may be
  split across multiple source-code files.
• Purpose
• Very large classes
• Separation of concerns
• Multiple developer

10
Windows Forms

• Forms are contained within a namespace called
  System.Windows.Forms that contains around 200
  classes, 100 enumeration, more than 40 delegates,
  7 interfaces, and 4 structures.
• The inheritance lineage is
• Object -gt
• MarshallByRefObject -gt
• Component-gt
• Control-gt
• ScrollableControl-gt
• Form

11
Windows Forms
12
SimpleForm.cs

• using System
• using System.Windows.Forms
• class SimpleForm
• static void Main()
• Form f1 new Form()
• f1.Text "My Simple Form"
• Application.Run(f1)

csc /twinexe SimpleForm.cs
13
SimpleForm2.cs

• using System
• using System.Windows.Forms
• class SimpleForm
• static void Main()
• Form f1 new Form()
• f1.Text "My Simple Form2"
• f1.Show()

What is the output?
14
SimpleForm3.cs

• using System.Threading
• using System.Windows.Forms
• class SimpleForm
• static void Main()
• Form f1 new Form()
• f1.Text "My Simple Form3"
• f1.Show()
• f1.Text "Time to sleep"
• //Let the process go to sleep for 1000 ms
  (pause)
• Thread.Sleep(3000)
• f1.Text "Time to wake up !"
• //Let the process go to sleep for 1000 ms
  (pause)
• Thread.Sleep(1000)

What is the output?
15
SimpleForm4.cs

• using System.Threading
• using System.Windows.Forms
• class SimpleForm
• public static void Main()
• Form f1 new Form()
• f1.Text "What is wrong with this?"
• f1.Visible true Thread.Sleep(3000)
• f1.Visible false Thread.Sleep(3000)
• f1.Text "Coming back to live"
• f1.Visible true Thread.Sleep(3000)
• Application.Run()
• f1.Text "After Application.Run is
  called"

What is the output?
16
SimpleForm5.cs

• using System.Threading
• using System.Windows.Forms
• class SimpleForm
• public static void Main()
• Form f1 new Form()
• f1.Text "What is wrong with this?"
• f1.Visible true Thread.Sleep(3000)
• f1.Visible false Thread.Sleep(3000)
• f1.Text "Coming back to live"
• f1.Visible true Thread.Sleep(3000)
• Application.Run(f1)
• Thread.Sleep(3000)
• f1.Text "After Application.Run is
  called"

What is the output?
17
SimpleForm6.cs

• using System.Threading
• using System.Windows.Forms
• class SimpleForm
• public static void Main()
• Form f1 new Form()
• f1.Text "How are you all doing?"
• f1.Visible true
• Thread.Sleep(3000)
• f1.Text "And How is your Baba?"
• Application.Run(f1)
• Thread.Sleep(3000)
• f1.Text "After Application.Run is
  called"
• MessageBox.Show("And your Daddy too?")

What is the output?
18
Conclusion

• Main creates the form and displays it.
• The form is given to Application.Run where it
  continues to exist.
• The form takes control of execution until the
  form is dismissed.
• When the form is dismissed, presumably, the
  Application.Run method continues (err, ends).
• The Application.Run method returns control to
  Main, which then calls the MessageBox.Show
  method.
• The application ends after the MessageBox is
  dismissed

19
SimpleForm7.cs

• using System.Threading
• using System.Windows.Forms
• class SimpleForm
• public static void Main()
• Form f0 new Form() f0.Text "How are
  you?"
• Form f1 new Form() f1.Text "How is
  C?"
• Form f2 new Form() f2.Text "How is
  C"
• f0.Show() f2.Show()
• Application.Run(f1)
• MessageBox.Show("Where are we?")
• f2.Text "F2, after Application.Run is
  called"
• Thread.Sleep(3000)

Take Home Bring back your description Quiz
20
Not Very Simple Windows Application!

• Drag and drop textbox and button from the toolbox
  into the Form
• Lets see what happened to our three files.
• Program.cs Form1.cs Form1.Designer.cs

21
Program.cs

• using System
• using System.Collections.Generic
• using System.Windows.Forms
• namespace SimpleApplication
• static class Program
• /// ltsummarygt
• /// The main entry point for the
  application.
• /// lt/summarygt
• STAThread
• static void Main()
• Application.EnableVisualStyles()
• Application.SetCompatibleTextRendering
  Default(false)
• Application.Run(new Form1())

NO CHANGES!
22
Form1.cs

• using System
• using System.Collections.Generic
• using System.ComponentModel
• using System.Data
• using System.Drawing
• using System.Text
• using System.Windows.Forms
• namespace SimpleApplication
• public partial class Form1 Form
• public Form1()
• InitializeComponent()

NO CHANGES!
23
Form1.Designer.cs

• namespace SimpleApplication
• partial class Form1
• //SAME AS BEFORE CODE OMMITED FOR SPACE
• private System.Windows.Forms.TextBox
  textBox1
• private System.Windows.Forms.Button
  button1
• private void InitializeComponent()
• this.textBox1 new System.Windows.Forms.TextBox(
  )
• this.button1 new System.Windows.Form
  s.Button()
• this.SuspendLayout()
• // textBox1
• this.textBox1.Location new
  System.Drawing.Point(72, 24)
• this.textBox1.Name "textBox1"
• this.textBox1.Size new
  System.Drawing.Size(100, 20)
• this.textBox1.TabIndex 0
• // button1
• this.button1.Location new
  System.Drawing.Point(82, 59)

We have two new fields
The fields properties are initialized
The fields are attached to the Form
24
Not Simple Windows Application!

• Lets say I want to find the square of the number
  entered
• Double click on the button, and suddenly Form1.cs
  is opened for me and the following code is
  displayed for me.

25
Form1.cs

• using System
• using System.Collections.Generic
• using System.ComponentModel
• using System.Data
• using System.Drawing
• using System.Text
• using System.Windows.Forms
• namespace SimpleApplication
• public partial class Form1 Form
• public Form1()
• InitializeComponent()
• private void button1_Click(object sender,
  EventArgs e)

This method is written for me
I wrote this code
26
Form1.Designer.cs

• namespace SimpleApplication
• partial class Form1
• //SAME AS BEFORE CODE OMMITED FOR SPACE
• //THE BUTTON1 IS THE PART THAT CHANGES
• // button1
• //
• this.button1.Location new
  System.Drawing.Point(82, 59)
• this.button1.Name "button1"
• this.button1.Size new
  System.Drawing.Size(75, 23)
• this.button1.TabIndex 1
• this.button1.Text "button1"
• this.button1.UseVisualStyleBackColor
  true
• this.button1.Click new
  System.EventHandler(this.button1_Click)

control
Event
Event handler (method name)
27
What We Just Did?

• We have attached an event handler for the click
  event.
• Button has Click event
• If this event happens (some one clicks on the
  button)
• button1_Click method will be executed.

28
SimpleForm8.csI like this code..

• using System
• using System.Threading
• using System.Windows.Forms
• class SimpleForm
• public static void Main()
• MyForm f1 new MyForm()
• Application.Run(f1)
• class MyForm Form
• private TextBox textBox1
• private Button button1
• public MyForm()