As you learn about keyboard event
in my previous article and learn that the Input Events divided into three
categories Keyboard events, Mouse events, Stylus events. This part of article explain about
the Mouse events.
Mouse Events:
There are so many tasks which performed by the mouse event but the most
fundamental events you to react when the mouse is moved over an element. Both
are direct events, which means they don't use tunneling or bubbling. Instead,
they originate in one element and are raised by just that element. This makes
sense because of the way controls are nested in a WPF window. All mouse button
events provide a MouseButtonEventArgs object. The MouseButtonEventArgs class
derives from MouseEventArgs (which means it includes the same coordinate and
button state information) and it adds a few members.
Example of the Mouse Event
Xaml Code
<Grid
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/interactivedesigner/2006"
mc:Ignorable="d"
x:Class="InputExamples.MousePosition"
Width="640"
Height="480">
<Label
d:LayoutOverrides="Height"
x:Name="firstCoordinates"/>
<Rectangle
Stroke="#FF000000"
Fill="#FFFFFFFF"
x:Name="Rectangle"/>
<Rectangle
Stroke="#FF000000"
Fill="#FFFFFFFF"
x:Name="secondEllipse"/>
<Ellipse
d:LayoutOverrides="Height"
Stroke="#FF000000"
Width="14"
Height="14"
x:Name="firstEllipse"/>
<Ellipse
d:LayoutOverrides="Width"
Stroke="#FF000000"
Width="14"
Height="14"
x:Name="fourthEllipse"/>
<Ellipse
d:LayoutOverrides="Width"
Stroke="#FF000000"
Width="14"
Height="14"
x:Name="thirdEllipse"/>
<Label
d:LayoutOverrides="Width,
Height"
x:Name="secondCoordinates"
Margin="287,254,0,192"
HorizontalAlignment="Left"
Width="117"
/>
<Label
d:LayoutOverrides="Width,
Height"
Width="100"
x:Name="thirdCoordinates"
Margin="422,254,118,192"
/>
<Label
d:LayoutOverrides="Width,
Height"
x:Name="fourthCoordinates"
Margin="137,257,378,192"
/>
<Rectangle
Fill="blue"
Width="16"
Height="16"
x:Name="DragEllipse"
Margin="311,232,313,232"
/>
</Grid>
Vb Code
Imports System
Imports
System.Net
Imports
System.Windows
Imports
System.Windows.Controls
Imports
System.Windows.Data
Imports
System.Windows.Input
Imports
System.Windows.Media
Imports
System.Windows.Media.Animation
Imports
System.Windows.Navigation
Imports
System.Windows.Shapes
Namespace
InputExamples
Partial Public Class MousePosition
Private ellipseTransform
As New TranslateTransform()
Public Sub New()
Me.InitializeComponent()
End Sub
Protected Overrides Sub
OnInitialized(ByVal e
As EventArgs)
MyBase.OnInitialized(e)
DragEllipse.RenderTransform = ellipseTransform
AddHandler CompositionTarget.Rendering,
AddressOf Me.CompositionTarget_Rendering
End Sub
Private Sub
CompositionTarget_Rendering(ByVal sender
As Object,
ByVal e As EventArgs)
Dim mouse1
As Point =
Mouse.GetPosition(firstEllipse)
Dim mouse2
As Point =
Mouse.GetPosition(secondEllipse)
Dim mouse3
As Point =
Mouse.GetPosition(thirdEllipse)
Dim mouse4
As Point =
Mouse.GetPosition(fourthEllipse)
firstCoordinates.Content = mouse1.ToString()
secondCoordinates.Content = mouse2.ToString()
thirdCoordinates.Content = mouse3.ToString()
fourthCoordinates.Content = mouse4.ToString()
Dim position
As Point =
Mouse.GetPosition(DragEllipse)
ellipseTransform.X += position.X - (DragEllipse.Width / 2)
ellipseTransform.Y += position.Y - (DragEllipse.Height / 2)
End Sub
End Class
End Namespace
Output Window
Conclusion
Hope this article helps you to understand the
Input Events in WPF. Remaining part of this article you will see in my next
article.