Silverlight - ListBox


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Listbox is a control that provides a list of items to the user for selection of an item. A user can select one or more items from a predefined list of items at a time. In a ListBox, multiple options are always visible to the user without any user interaction.

A Listbox presents a scrollable list of items. If a user selects an item, the selected item changes appearance to indicate selection. It supports a more extensive form of content model and Button. A major difference between a button and a list box is that a button contains a single piece of content whereas a listbox allows every single item in the list.

The hierarchical inheritance of ListBox class is as follows −

Inheritance Listbox

Given below are the commonly used Properties of ListBox class.

Sr. No. Property & Description
1

Background

Gets or sets a brush that provides the background of the control. (Inherited from Control)

2

BorderThickness

Gets or sets the border thickness of a control. (Inherited from Control)

3

FontFamily

Gets or sets the font used to display text in the control. (Inherited from Control)

4

FontSize

Gets or sets the size of the text in this control. (Inherited from Control)

5

FontStyle

Gets or sets the style in which the text is rendered. (Inherited from Control)

6

FontWeight

Gets or sets the thickness of the specified font. (Inherited from Control)

7

Foreground

Gets or sets a brush that describes the foreground color. (Inherited from Control)

8

GroupStyle

Gets a collection of GroupStyle objects that define the appearance of each level of groups. (Inherited from ItemsControl)

9

Height

Gets or sets the suggested height of a FrameworkElement. (Inherited from FrameworkElement)

10

HorizontalAlignment

Gets or sets the horizontal alignment characteristics that are applied to a FrameworkElement when it is composed in a layout parent, such as a panel or items control. (Inherited from FrameworkElement)

11

IsEnabled

Gets or sets a value indicating whether the user can interact with the control. (Inherited from Control)

12

Item

Gets the collection used to generate the content of the control. (Inherited from ItemsControl)

13

ItemsSource

Gets or sets an object source used to generate the content of the ItemsControl. (Inherited from ItemsControl)

14

Margin

Gets or sets the outer margin of a FrameworkElement. (Inherited from FrameworkElement)

15

Name

Gets or sets the identifying name of the object. When a XAML processor creates the object tree from XAML markup, run-time code can refer to the XAML-declared object by this name. (Inherited from FrameworkElement)

16

Opacity

Gets or sets the degree of the object's opacity. (Inherited from UIElement)

17

SelectedIndex

Gets or sets the index of the selected item. (Inherited from Selector)

18

SelectedItem

Gets or sets the selected item. (Inherited from Selector)

19

SelectedValue

Gets or sets the value of the selected item, obtained by using the SelectedValuePath. (Inherited from Selector)

20

Style

Gets or sets an instance Style that is applied for this object during layout and rendering. (Inherited from FrameworkElement)

21

VerticalAlignment

Gets or sets the vertical alignment characteristics that are applied to a FrameworkElement when it is composed in a parent object such as a panel or items control. (Inherited from FrameworkElement)

22

Width

Gets or sets the width of a FrameworkElement. (Inherited from FrameworkElement)

Given below are the most commonly used Events of ListBox.

Sr. No. Event & Description
1

DragEnter

Occurs when the input system reports an underlying drag event with this element as the target. (Inherited from UIElement)

2

DragLeave

Occurs when the input system reports an underlying drag event with this element as the origin. (Inherited from UIElement)

3

DragOver

Occurs when the input system reports an underlying drag event with this element as the potential drop target. (Inherited from UIElement)

4

DragStarting

Occurs when a drag operation is initiated. (Inherited from UIElement)

5

Drop

Occurs when the input system reports an underlying drop event with this element as the drop target. (Inherited from UIElement)

6

DropCompleted

Occurs when a drag-and-drop operation is ended. (Inherited from UIElement)

7

GotFocus

Occurs when a UIElement receives focus. (Inherited from UIElement)

8

IsEnabledChanged

Occurs when the IsEnabled property changes. (Inherited from Control)

9

KeyDown

Occurs when a keyboard key is pressed while the UIElement has focus. (Inherited from UIElement)

10

KeyUp

Occurs when a keyboard key is released while the UIElement has focus. (Inherited from UIElement)

11

LostFocus

Occurs when a UIElement loses focus. (Inherited from UIElement)

12

SelectionChanged

Occurs when the currently selected item changes. (Inherited from Selector)

13

SizeChanged

Occurs when either the ActualHeight or the ActualWidth property changes value on a FrameworkElement. (Inherited from FrameworkElement)

Given below are the most commonly used Methods of ListBox.

Sr. No. Method & Description
1

Arrange

Positions child objects and determines a size for a UIElement. Parent objects that implement custom layout for their child elements should call this method from their layout override implementations to form a recursive layout update. (Inherited from UIElement)

2

FindName

Retrieves an object that has the specified identifier name. (Inherited from FrameworkElement)

3

Focus

Attempts to set the focus on the control. (Inherited from Control)

4

GetValue

Returns the current effective value of a dependency property from a DependencyObject. (Inherited from DependencyObject)

5

IndexFromContainer

Returns the index to the item that has the specified, generated container. (Inherited from ItemsControl)

6

OnDragEnter

Called before the DragEnter event occurs. (Inherited from Control)

7

OnDragLeave

Called before the DragLeave event occurs. (Inherited from Control)

8

OnDragOver

Called before the DragOver event occurs. (Inherited from Control)

9

OnDrop

Called before the Drop event occurs. (Inherited from Control)

10

OnKeyDown

Called before the KeyDown event occurs. (Inherited from Control)

11

OnKeyUp

Called before the KeyUp event occurs. (Inherited from Control)

12

OnLostFocus

Called before the LostFocus event occurs. (Inherited from Control)

13

ReadLocalValue

Returns the local value of a dependency property, if a local value is set. (Inherited from DependencyObject)

14

SetBinding

Attaches a binding to a FrameworkElement, using the provided binding object. (Inherited from FrameworkElement)

15

SetValue

Sets the local value of a dependency property on a DependencyObject. (Inherited from DependencyObject)

Let us look at a simple example in which different UI elements are added in a ListBox.

<UserControl x:Class = "ListBoxExample.MainPage" 
   xmlns = "http://schemas.microsoft.com/winfx/2006/xaml/presentation"  
   xmlns:x = "http://schemas.microsoft.com/winfx/2006/xaml" 
   xmlns:d = "http://schemas.microsoft.com/expression/blend/2008" 
   xmlns:mc = "http://schemas.openxmlformats.org/markup-compatibility/2006"  
   mc:Ignorable = "d" d:DesignWidth = "640" d:DesignHeight = "480"> 
   
   <Grid x:Name = "LayoutRoot">
	
      <ListBox x:Name = "myList">
		
         <TextBlock Text = "First item" /> 
         <Button Content = "Second item" /> 
         <Path Fill = "Blue" Data = "M4,0 l-4,10 8,0z M15,0 l-4,10 8,0z M26,0 l4,10 8,0z" 
            Margin = "10" /> 
			
         <StackPanel Orientation = "Horizontal"> 
            <Ellipse Fill = "Red" Height = "30" Width = "100" /> 
            <TextBlock Text = "Name: " /> 
            <TextBox Width = "200" /> 
         </StackPanel>
			
         <TextBlock Text = "More..." /> 
			
      </ListBox> 
		
   </Grid>
	
</UserControl>

Given below is the C# implementation.

using System.Windows.Controls; 
 
namespace ListBoxExample { 

   public partial class MainPage : UserControl { 
	
      public MainPage() { 
         InitializeComponent();  
			
         myList.Items.Add("String entry"); 
         myList.Items.Add(new Button { Content = "Content entry" });  
      } 
   } 
}

When the above code is compiled and executed, you will see a list box which contains mixture of graphics text and also an editable field where you can type the text.

Add  UI Element in ListBox

Sr. No. Controls & Description
1 Calendar & DatePicker

Calendar & DatePicker represents a control that enables a user to select a date by using a visual calendar display. It provides some basic navigation using either the mouse or the keyboard.

2 TabControl

A container that places items into separate tabs and allows the user to view just one tab at a time. It allows the user to select from a number of different views by clicking on the tab headers.

3 Popup

This class displays the content on top of the existing content, within the bounds of the application window. It is a temporarily display on the other content.

4 ToolTip

Tooltip represents a control that creates a pop-up window that displays information for an element in the GUI. Silverlight lets you attach a tooltip to any control.



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