10
Programming
Based on
Events
C# Programming: From Problem Analysis to Program Design
3rd Edition
C# Programming: From Problem Analysis to Program Design
1
Part II
C# Programming: From Problem Analysis to Program Design
2
MenuStrip Controls
• Offers advantage of taking up minimal space
• Drag and drop MenuStrip object from toolbox to
your form
– Icon representing MenuStrip placed in Component Tray
• Select MenuStrip object to set its properties
• To add the text for a menu option, select the
MenuStrip icon and then click in the upper-left
corner of the form
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Adding Menus
Drag MenuStrip
control to form,
then click here to
display Menu
structure
Figure 10-9 First step to creating a menu
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MenuStrip Control Objects
• Ampersand (&) is typed between the F and o for the
Format option to make Alt+o shortcut for Format
Figure 10-10 Creating a shortcut for a menu item
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MenuStrip Control Objects
(continued)
• To create separators,
right-click on the text
label (below the
needed separator)
• Select Insert
Separator
Figure 10-11
Adding a separator
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MenuStrip Control Objects
(continued)
Set the text to
be displayed
when the
cursor is
rested on top
of the control
Figure 10-12 Setting the Property for the ToolTip control
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Wire Methods to Menu Option
Event
• Set the Name property for each menu option
– Do this first, then wire the event
• Click events are registered by double-clicking on
the Menu option
• When the menu option is clicked, the event
triggers, happens, or is fired
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Adding Predefined Standard
Windows Dialog Boxes
• Included as part of .NET
• Dialog boxes that look like standard Windows dialog
boxes
– File Open, File Save, File Print, and File Print
Preview
– Format Font
– Format Color dialogs
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Adding Predefined Standard
Windows Dialog Boxes – Color
Retrieves the
private void menuColor_Click(object sender,
current ForeColor
System.EventArgs e)
property setting
{
for the Label
object
colorDialog1.Color = lblOutput.ForeColor;
if (colorDialog1.ShowDialog( ) != DialogResult.Cancel )
{
Checks to see
lblOutput.ForeColor = colorDialog1.Color;
if Cancel
}
button clicked
}
Set to
selection
made
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Adding Predefined Standard Windows
Dialog Boxes – Color (continued)
Figure 10-14 Color dialog box menu option
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Adding Predefined Standard
Windows Dialog Boxes – Font
private void menuFont_Click
(object sender,
System.EventArgs e)
{
fontDialog1.Font =
lblOutput.Font;
if (fontDialog1.ShowDialog( )
!= DialogResult.Cancel )
{
lblOutput.Font =
Figure 10-15
fontDialog1.Font ;
Font dialog box menu option
}
} C# Programming: From Problem Analysis to Program Design
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CheckBox Objects
• Appear as small boxes
– Allow users to make a yes/no or true/false selection
• Checked property set to either true or false
depending on whether a check mark appears or not
– Default false value
• CheckChanged( ) – default event-handler method
– Fired when CheckBox object states change
• Can wire one event handler to multiple objects
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Wiring One Event Handler to
Multiple Objects
•
•
•
•
Using Properties window, click on the Events Icon
Click the down arrow associated with that event
Select method to handle the event
Follow the same steps for other objects
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Wiring One Event Handler to
Multiple Objects (continued)
Figure 10-16 Wiring the event-handler method
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CheckBox Object
Figure 10-17 ComputeCost_CheckedChanged( ) method raised
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GroupBox Objects
• CheckBox objects may be grouped together for
visual appearance
• Can move or set properties that impact the entire
group
• A GroupBox control should be placed on the form
before you add objects
• GroupBox control adds functionality to
RadioButton objects
– Allow only one selection
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RadioButton Objects
• Appear as small circles
• Give users a choice between two or more options
– Not appropriate to select more than one CheckBox
object with RadioButton objects
• Group RadioButton objects by placing them on a
Panel or GroupBox control
– Setting the Text property for the GroupBox adds a
labeled heading over the group
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Adding RadioButton Objects
Figure 10-18 GroupBox and RadioButton objects added
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RadioButton Objects (continued)
• Turn selection on
this.radInterm.Checked = true;
• Raise a number of events, including Click( ) and
CheckedChanged( ) events
• Wire the event-handler methods for RadioButton
objects, just like CheckBox
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Registering RadioButton Object
Events
• Register ComputeCost_CheckedChanged( )
method
Figure 10-19 Wired Click event
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RadioButton Objects (continued)
• ComputeCost_CheckedChanged( ) method
if (this.radBeginner.Checked)
{
cost +=10;
this.lblMsg.Text =
"Beginner “ +
“-- Extra $10 charge";
}
else
// more statements
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ComputeCost_CheckChanged( ) and
Click( ) Events Raised
Figure 10-20 ComputeCost_CheckedChanged( ) and Click( )
events raised
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Windows Presentation
Foundation
• WPF
• Interface for Visual Studio 2010 was built using
WPF
• Vector-based and resolution-independent ->sharp
graphics
• As with WinForms, drag and drop controls from
the Toolbox onto the window
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Windows Presentation
Foundation (WPF)
Figure 10-19 WPF design
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TabControl Controls
• Sometime an application requires too many
controls for a single screen
• TabControl object displays multiple tabs, like
dividers in a notebook
• Each separate tab can be clicked to display other
options
• Add a TabControl object to the page by dragging
the control from the Container section of the
Toolbox
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TabControl Controls (continued)
Figure 10-21 Tabbed controlled application
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TabControl Controls (continued)
Figure 10-22 TabControl object stretched to fill form
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TabControl Controls (continued)
• TabPage property
enables you to
format individual
tabs
• Clicking the
ellipsis beside the
Collection value
displays the
TabPage
Collection Editor
Figure 10-23 TabControl's TabPage Collection
Editor
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DinerGui
Application
Example
Figure 10-24 Problem specification for DinerGUI example
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DinerGui Application Example
(continued)
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DinerGui Application Example
(continued)
Figure 10-25 Prototype for DinerGUI example
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DinerGui
Application
Example (continued)
Figure 10-26
Class diagrams
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DinerGui Application Example
(continued)
Figure 10-33 Message displayed from Current Order menu option
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Coding Standards
• Follow a consistent naming standard for controls
• Before you register events, such as button click
events, name the associated control
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Chapter Summary
• Delegates
• Event-handling procedures
– Registering an event
• ListBox control for multiple selections
• ComboBox versus ListBox objects
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Chapter Summary (continued)
• Adding controls to save space
– MenuStrip controls
– TabControl
• Use of GroupBox controls
• RadioButton versus CheckBox objects
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