Chapter 13: Advanced GUI and Graphics Visual Basic .NET Programming: From Problem Analysis to Program Design

Visual Basic .NET Programming: From Problem Analysis to Program Design Objectives Work with additional GUI controls Draw lines, rectangles, and ovals Develop GUI classes that interact with a PD class Create applications with multiple forms Simulate a DA class Create an integrated system that simulates interaction with a database Visual Basic .NET Programming: From Problem Analysis to Program Design

Working with Additional GUI Controls Other GUI components: Menus Group boxes Tab pages Namespace: System.Windows.Forms Control Superclass of other GUI classes Visual Basic .NET Programming: From Problem Analysis to Program Design

Visual Basic .NET Programming: From Problem Analysis to Program Design

Using Group Boxes and Panels Containers Enable you to visually and logically organize groups of related controls Add components By drawing them inside group box or panel Move panel or group box All controls within it move together Common use of group boxes and panels Group set of radio buttons Visual Basic .NET Programming: From Problem Analysis to Program Design

Visual Basic .NET Programming: From Problem Analysis to Program Design

Visual Basic .NET Programming: From Problem Analysis to Program Design

Visual Basic .NET Programming: From Problem Analysis to Program Design

Using Tree Nodes and Tree Views Displays group of hierarchically related items Each item is represented as instance of TreeNode class Useful for displaying hierarchical information Visual Basic .NET Programming: From Problem Analysis to Program Design

Visual Basic .NET Programming: From Problem Analysis to Program Design

Using Tree Nodes and Tree Views (continued) Has a value Types: Parent Child Sibling Visual Basic .NET Programming: From Problem Analysis to Program Design

Visual Basic .NET Programming: From Problem Analysis to Program Design

Visual Basic .NET Programming: From Problem Analysis to Program Design

Example 13-2: Using Tree Views and Tree Nodes Declaring variables: Dim rootNode, profNode As TreeNode Adding to tree: control.Nodes.Add(myString) Finding selected node: myNode = trvCSC.SelectedNode Visual Basic .NET Programming: From Problem Analysis to Program Design

Example 13-2: Using Tree Views and Tree Nodes (continued) Accessing related nodes: myNode.Parent myNode.PrevNode myNode.NextNode Accessing node text: myNode.NextNode.Text Visual Basic .NET Programming: From Problem Analysis to Program Design

Using Tab Controls and Tab Pages Provides functionality for set of tab pages Instance of TabPage class Useful when Form requires large number of controls Controls can be grouped into logical subsets User switches between subsets by clicking appropriate tab Visual Basic .NET Programming: From Problem Analysis to Program Design

Visual Basic .NET Programming: From Problem Analysis to Program Design

Visual Basic .NET Programming: From Problem Analysis to Program Design

Visual Basic .NET Programming: From Problem Analysis to Program Design

Using Main Menus and Menu Items MainMenu and MenuItem classes Create menus and submenus for a form Main menu control Serves as container for menu structure Menu items Represent individual menu choices within structure Visual Basic .NET Programming: From Problem Analysis to Program Design

Using Main Menus and Menu Items (continued) Menu purposes: Provide functionality for common tasks, such as Opening and closing files Editing text Accessing help features Can use menus instead of buttons to perform many tasks Visual Basic .NET Programming: From Problem Analysis to Program Design

Visual Basic .NET Programming: From Problem Analysis to Program Design

Visual Basic .NET Programming: From Problem Analysis to Program Design

Visual Basic .NET Programming: From Problem Analysis to Program Design

Visual Basic .NET Programming: From Problem Analysis to Program Design

Drawing Lines, Rectangles, and Ovals VB .NET includes a rich set of classes for drawing graphical elements System.Drawing namespace Contains classes and structures needed for drawing graphical objects Automatically available in Windows applications No need to import namespace Visual Basic .NET Programming: From Problem Analysis to Program Design

Drawing Lines, Rectangles, and Ovals (continued) Structure Can include: Constructors Methods Properties Events Value type Variable contains actual data for structure Visual Basic .NET Programming: From Problem Analysis to Program Design

Visual Basic .NET Programming: From Problem Analysis to Program Design

Visual Basic .NET Programming: From Problem Analysis to Program Design

Example 13-5: Using Graphics Generate paint event for form: Invalidate() Event handler parameters Sender Reference to object that raised event e Object specific to event being handled Visual Basic .NET Programming: From Problem Analysis to Program Design

Example 13-5: Using Graphics (continued) 'declare variables needed for drawing Dim instrumentColor As Color Dim myBrush As SolidBrush Dim myPen As Pen Visual Basic .NET Programming: From Problem Analysis to Program Design

Example 13-5: Using Graphics (continued) 'draw a white rectangle to serve as drawing canvas g.FillRectangle(New SolidBrush(Color.White), 18, 160, 492, 248) 'Define a brush using the selected Color myBrush = New SolidBrush(instrumentColor) 'Define a pen using the selected Color myPen = New Pen(instrumentColor) Visual Basic .NET Programming: From Problem Analysis to Program Design

Developing GUI Classes that Interact With a PD Class Create GUIs that interact with problem domain (PD) class Customer PD class contains Three attributes: Name Address PhoneNo Parameterized constructor, Get and set accessor methods Visual Basic .NET Programming: From Problem Analysis to Program Design

Visual Basic .NET Programming: From Problem Analysis to Program Design Adding a Customer Visual programming process Generates variables necessary to create GUI Does not generate all variables needed to respond to events Variables must be added to source code through the Code Editor window Visual Basic .NET Programming: From Problem Analysis to Program Design

Visual Basic .NET Programming: From Problem Analysis to Program Design Finding a Customer Use ArrayList to simulate interaction with database Customer instances created from hard-coded data Visual Basic .NET Programming: From Problem Analysis to Program Design

Creating Applications with Multiple Forms Link multiple forms through GUI that allows you to navigate between forms Referred to as main menu GUI Uses buttons to navigate between forms Event handlers hide and show forms: frmAddCustomerGUI.ShowDialog() Me.Show() Visual Basic .NET Programming: From Problem Analysis to Program Design

Creating Applications with Multiple Forms (continued) Modal dialog box Form must be dismissed before next statement in procedure will be executed Use ShowDialog method Data Access (DA) class Enables sharing of data among forms Visual Basic .NET Programming: From Problem Analysis to Program Design

Visual Basic .NET Programming: From Problem Analysis to Program Design

Visual Basic .NET Programming: From Problem Analysis to Program Design Simulating a DA Class Simulate interaction with database by using ArrayList of customers DA classes provide data storage and retrieval services Visual Basic .NET Programming: From Problem Analysis to Program Design

Simulating a DA Class (continued) DA methods Initialize GetAll AddNew Find Update Visual Basic .NET Programming: From Problem Analysis to Program Design

Visual Basic .NET Programming: From Problem Analysis to Program Design Creating an Integrated System that Simulates Interaction With a Database Modify previously developed forms to use DA class Visual Basic .NET Programming: From Problem Analysis to Program Design

Modifying the Main Menu Form Initialize simulated database By invoking Initialize method of CustomerDA class Invoked by event handler for Load event Visual Basic .NET Programming: From Problem Analysis to Program Design

Modifying the Add Customer Form Event handler for Add Customer button Invokes AddNew method of DA class To add Customer instance to simulated database Visual Basic .NET Programming: From Problem Analysis to Program Design

Modifying the Find Customer Form Does not include CreateCustomers method PopulateListBox method now invokes DA class method GetAll To obtain ArrayList Event handler for list box Invokes DA class method Find Event handler for Update button Invokes DA class method Update Visual Basic .NET Programming: From Problem Analysis to Program Design

Programming Example: Interacting with Multiple PD Classes Person Student Professor Phone DA classes: professor Visual Basic .NET Programming: From Problem Analysis to Program Design

Visual Basic .NET Programming: From Problem Analysis to Program Design

Visual Basic .NET Programming: From Problem Analysis to Program Design Summary Group boxes and panels Containers that enable you to visually and logically organize groups of related controls Tree view Displays group of hierarchically related items as expandable outline Tab control Provides functionality for a set of tab pages Visual Basic .NET Programming: From Problem Analysis to Program Design

Visual Basic .NET Programming: From Problem Analysis to Program Design Summary (continued) Main menu control Serves as container for menu structure Menu items Represent individual menu choices within that structure Graphics class contains methods for drawing shapes Structures are value types Visual Basic .NET Programming: From Problem Analysis to Program Design

Visual Basic .NET Programming: From Problem Analysis to Program Design Summary (continued) Event handlers provide two parameters: Sender e Graphical user interface (GUI) classes can interact with problem domain (PD) and data access (DA) classes Visual Basic .NET Programming: From Problem Analysis to Program Design