Graphical User Interfaces with Windows Forms

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Graphical User Interfaces with Windows Forms
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Visual Studio Form Designer

• For designing forms, changing the properties or
  adding events to forms and form elements can be
  achieved with the Visual Studio Form Designer
• Toolbox
• Properties
• Lets have a look!

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Visual Studio Form Designer

• Design this form

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Event Management

• In order to address handler methods we need a
  delegate and an event defined for form objects
• EventHandler object is a pre-defined delegate for
  working with form events
• Every form element and the form itself have
  pre-defined events like Click, MouseClick,
  Keydown, Keypressed

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Example Button Click Event
firstButton new Button() firstButton.Text
"Click Me!" firstButton.Location new Point(50,
50) firstButton.Size new Size(150,
50) firstButton.Click new EventHandler(firstBu
tton_Click) void firstButton_Click(object
sender, EventArgs e) MessageBox.Show("Butto
n clicked!")
Adding an event handler to button
Handler method for button click event
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Examining Designer Generated Code

• All element initializations like buttons or the
  form itself occur under InitializeComponent()
  method
• Designer seperates the actual class and its
  design using the partial class declaration
• User class Form1.cs
• Designer generated class Form1.Designer.cs

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Some of Common Controls
Controls
Containers

• Button
• CheckBox
• ComboBox
• DateTimePicker
• Label
• ListBox
• RadioButton
• TextBox
• ToolTip

• Panel
• GroupBox
• SplitContainer
• TabControl

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Some General Properties and Events for Form
Controls
Events
Properties

• Location
• (Point)
• Text
• Name
• TabIndex
• Visible
• Enabled
• Dock

• Click
• MouseClick
• MouseOver
• MouseLeave
• KeyDown
• KeyPress
• Paint
• TextChanged

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Message Boxes

• Can be used for giving info to users or getting
  input from them
• Returns a DialogueResult object when a button is
  clicked

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Hands On - Coordinate Displayer

• Display the x and y locations of the mouse
  position on a tooltip

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Hands On Creating a Layout

• Create a layout with two columns and a
  StatusStrip
• On the left column insert a ListBox
• On the right column insert a TextBox
• As mouse enters a component show which component
  entered on the StatusStrip
• Add items to ListBox, when user clicks an item it
  should be added to the TextBox

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Hands On Text Formatter

• Create a form with an editable text box
• Users should be able to change the style of the
  text in the textbox using comboboxes,
  radiobuttons, etc

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Working with Multiple Forms

• Multiple forms can be used in an application
• In order to call another form we call Show()
  method of the Form class

MyForm frm2 new MyForm() frm2.Show()

• As you have the reference to the new form you can
  change the properties of it using that reference

frm2.label1.Text "New form opened" frm2.Text
"This is a new form"
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Working with Multiple Forms - MDI Forms

• MDI forms can show other form instances inside
  themselves
• In order to create an mdi form
• Set the isMdiContainer property of the main
  form to true
• Then create a new form as usual and set its
  MdiParent property to true and show the form

FrmChild frmChild new FrmChild()
frmChild.MdiParent this frmChild.Show()
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Hands On Multiple Forms

• Get the name and surname of the user via a form
  and show the information with the date and time
  in a new form
• When main form is closing ask the user if he/she
  is sure to exit

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Menus

• Two types of menu
• MenuStrip ? Menu residing at the top of forms,
  contains MenuItem objects
• ContextMenu ? Menu appears when mouse right
  clicked on a component

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Best Practices Forms and Events

• In order to reach fields of a child form from the
  main form, just use child forms reference
• If a message will be sent from the child form to
  the main form, use events
• Child form will have an event to fire
• In the main form an event handler should be
  registered to the the child form

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Hands On Customer Registration

• Create one main form and a child form
• In the main form insert a menu with an Add
  Customer menu item
• The child form will include text boxes for name
  and surname of the customer
• When a new customer is saved it should be listed
  in a list box in your main form

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Hands On (Contd)
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Timer Control

• It is for calling methods in pre-defined time
  intervals (so are like threads)
• Properties
• Interval time intervals for methods to be
  executed in milliseconds
• Enabled for timer to execute, this property
  should be set True
• Tick Event Event fired when an interval is
  complete