Microsoft VB 2005: Reloaded, Advanced

1
Microsoft VB 2005 Reloaded, Advanced

• Chapter 6
• More about Windows Forms

2
Objectives

• Understand program code generated by Visual Basic
  for user interfaces
• Create a user interface with a flow layout and a
  table layout
• Create a user interface with tabbed pages and
  dialog forms
• Create a user interface with a menu and shortcut
  keys
• Create an application with a multiple document
  interface (MDI)

3
A Closer Look at GUIs

• Objective
• Understand the code generated by Visual Basic as
  you build a GUI

4
Forms and Components

• Form
• Window or dialog box that makes up an
  applications graphical user interface
• Instance of the class System.Windows.Forms.Form
• Component
• Object that is added to a form to provide
  functionality
• Control
• Visible component derived from the Control class

5
The Event-Handling Model

• Event
• A message indicating that a user action has
  occurred
• Event-driven applications
• GUIs generate events (via user actions) that
  drive the applications functionality
• Event-handlers
• Methods written by the programmer to provide the
  application with the desired responses to events
• Visual Basic uses a MulticastDelegate object to
  implement event handling

6
The Event-Handling Model (continued)

• Delegate
• An instance of the Delegate class
• Delegate class
• Data structure that refers to either
• A static method
• A class instance and an instance method of that
  class
• An event generated by a GUI calls a delegate that
  is registered for that event
• Delegate in turn calls all methods (static
  methods or instance methods) that it references

7
Visual Basic Generated Code for GUIs

• When you create a GUI using the Visual Basic Form
  Designer
• Visual Basic generates the required program code
  in the Code window
• View code by right-clicking the open space in the
  Windows Form Designer, outside the form
• And then clicking View Code
• Details of the code for the GUI are hidden from
  view
• Figure 6.3 shows the code generated by Windows
  Form Designer

8
Visual Basic Generated Code for GUIs (continued)
9
Visual Basic Generated Code for GUIs (continued)
10
Enhancing a GUIs Appearance and Functionality

• Objective
• Learn tips for enhancing Windows application forms

11
Form Startup Location

• By default, a form will appear at the Windows
  default location
• Near the upper-left corner of the screen

12
Form Startup Location (continued)
13
Making a Form Scrollable

• A form may contain more controls than will fit
  within the boundaries of the form
• You can make your form scrollable with scroll
  bars that appear only when necessary
• Select True for the Autoscroll property value

14
Making a Form Scrollable (continued)
15
Making a Form Scrollable (continued)
16
Making a Form Scrollable (continued)
17
The FlowLayoutPanel Control
18
The FlowLayoutPanel Control (continued)
19
The Margin and Padding Properties

• Margin property
• Determines the amount of space, in pixels,
  reserved around a control
• When calculating its automatic position in a
  FlowLayoutPanel
• Padding property
• Determines the amount of space, in pixels,
  reserved along the inside of containers

20
The Margin and Padding Properties (continued)
21
The TableLayoutPanel Control

• Allows you to create a rectangular grid of rows
  and columns in which other controls can be placed
• Helps maintain an organized appearance for the
  form

22
The TableLayoutPanel Control (continued)
23
The TableLayoutPanel Control (continued)
24
The TableLayoutPanel Control (continued)
25
The TableLayoutPanel Control (continued)
26
The TabControl Control

• Allows you to create a form with several related
  tabbed pages
• Can consist of two or more TabPage controls, each
  of which can contain various other controls

27
The TabControl Control (continued)
28
The TabControl Control (continued)
29
Dialog Forms

• Dialog form
• Modal form that can return standard results using
  the DialogResult property
• Convenient way of getting quick standard
  responses
• Displayed using the ShowDialog method
• Modal form
• Requires the user to close the form before
  activating another window in the application
• Modeless form
• Does not have this requirement

30
Dialog Forms (continued)
31
Menus

• One of the best ways of organizing a larger
  number of commands is with menus

32
About Menus

• Menu
• List of items that specify options or groups of
  options for an application
• Menu items
• Represent the individual menu commands in a menu
• A menu item can be a parent menu for other
  submenu items
• Shortcut key
• Single key or a combination of keys that the user
  can press to execute a menu item

33
Implementing Menus

• Adding a menu
• With an empty form displayed in the Designer
• Drag a MenuStrip control from the Toolbox to any
  part in the form
• Adding a menu item
• See Figure 6.24

34
Implementing Menus (continued)
35
Implementing Menus (continued)
36
Implementing Menus (continued)

• Adding shortcut keys
• See Figure 6.26 and Figure 6.27
• Adding functionality to menu items
• See Figure 6.29

37
Implementing Menus (continued)
38
Implementing Menus (continued)
39
Multiple-Document-Interface Windows

• Single-document-interface (SDI) applications
• Applications that support only one open window or
  document at a time
• Multiple-document-interface (MDI) applications
• Allow many documents to be open at once
• Allow the user to easily move from document to
  document
• The application window of an MDI program is
  called the parent window
• Each window in application is called a child
  window

40
Multiple-Document-Interface Windows (continued)
41
Multiple-Document-Interface Windows (continued)
42
Multiple-Document-Interface Windows (continued)

• Example
• Birthday application

43
Multiple-Document-Interface Windows (continued)
44
Multiple-Document-Interface Windows (continued)
45
Multiple-Document-Interface Windows (continued)
46
Multiple-Document-Interface Windows (continued)

• Properties, methods, and events associated with
  MDI forms
• See Table 6.1

47
Multiple-Document-Interface Windows (continued)
48
Multiple-Document-Interface Windows (continued)
49
Multiple-Document-Interface Windows (continued)
50
Summary

• A form is a graphical element that appears on the
  screen
• A component is an object that ultimately derives
  much of its functionality from the Component
  class
• When a user interacts with a control by using the
  mouse or the keyboard
• The control raises an event within the
  application
• When you create a GUI using the Visual Basic Form
  Designer
• Visual Basic generates the required program code
  in the Code window

51
Summary (continued)

• Enhancing GUIs
• StartPosition property
• AutoScroll property
• FlowLayoutPanel control
• Margin and Padding properties
• TableLayoutPanel control
• TabControl control
• A dialog form is a modal form that can return
  standard results using the DialogResult property

52
Summary (continued)

• A menu is a component of the MenuStrip class that
  represents the container for the menu structure
  of a form
• A menu contains menu items
• All menu items can have key shortcuts (or hot
  keys)
• MDI applications allow many documents to be
  opened at once