HowTo: .NET controls in Internet Explorer – natural behavior and look-and-feel
As for the way .net controls behave in Internet Explorer, it's Okay, Add-in Express will take care of it. As concerns their look-and-feel, we are going to scrutinize this issue closely today.
Standard .NET controls look rather clumsy in Internet Explorer. For example, this is how a usual ToolStrip looks like:
It is not perceived like a native IE control, the background is obviously different. Let's try to change its paint and make its look-and-feel more natural. We will need to use several Win32 API functions:
_ Public Shared Function LoadLibrary(ByVal lpFileName As String) As IntPtr End Function _ Public Shared Function GetProcAddress(ByVal hModule As IntPtr, _ ByVal lpProcName As String) As IntPtr End Function _ Public Shared Function FreeLibrary(ByVal hModule As IntPtr) As Boolean End Function
Now we create our own control:
Class MyCustomToolStrip
Inherits ToolStrip
Public Sub New()
MyBase.New()
If Not Me.DesignMode Then
Me.DoubleBuffered = True
hThemeModule = LoadLibrary("UxTheme.dll")
If hThemeModule <> IntPtr.Zero Then
Dim dllIsThemeActive As IntPtr = GetProcAddress _
(hThemeModule, "IsThemeActive")
If dllIsThemeActive <> IntPtr.Zero Then
IsThemeActive = DirectCast _
(Marshal.GetDelegateForFunctionPointer _
(dllIsThemeActive, GetType(DllIsThemeActive)), _
DllIsThemeActive)
End If
Dim dllDrawThemeParentBackground As IntPtr = _
GetProcAddress(hThemeModule, "DrawThemeParentBackground")
If dllDrawThemeParentBackground <> IntPtr.Zero Then
DrawThemeParentBackground = DirectCast _
(Marshal.GetDelegateForFunctionPointer _
(dllDrawThemeParentBackground, _
GetType(DllDrawThemeParentBackground)), _
DllDrawThemeParentBackground)
End If
Application.EnableVisualStyles()
Application.DoEvents()
End If
End If
End Sub
'
End Class
Repainting the background:
Protected Overrides Sub OnPaintBackground(ByVal e As PaintEventArgs) If hThemeModule <> IntPtr.Zero AndAlso Not DesignMode Then If IsThemeActive() Then Dim hdc As IntPtr = IntPtr.Zero Dim rect As New RECT(0, 0, Width, Height) hdc = e.Graphics.GetHdc() If hdc <> IntPtr.Zero Then Try DrawThemeParentBackground(Me.Handle, hdc, rect) Finally e.Graphics.ReleaseHdc(hdc) End Try End If Exit Sub End If End If MyBase.OnPaintBackground(e) End Sub
Modifying the Paint method a little bit:
Protected Overrides Sub OnPaint(ByVal e As PaintEventArgs) MyBase.OnPaint(e) If hThemeModule <> IntPtr.Zero AndAlso Not DesignMode Then If IsThemeActive() Then Dim hdc As IntPtr = IntPtr.Zero Dim rect As New RECT(0, Height - 2, Width, Height) hdc = e.Graphics.GetHdc() If hdc <> IntPtr.Zero Then Try DrawThemeParentBackground(Me.Handle, hdc, rect) Finally e.Graphics.ReleaseHdc(hdc) End Try End If End If End If End Sub
And, enjoying the result:
The difference is evident, isn't it?
You may also be interested in:
How to create an IE add-on step-by-step
How to build an IE toolbar with custom buttons
How to develop an Explorer bar and context menu
Available downloads:
This sample add-in was developed using
Add-in Express for Internet Explorer
C# sample IE add-on for VS 2005
VB.NET sample IE add-on for VS 2005
2 Comments
Hello!
Thanks for your post. It’s very intresting!!!
Now I’m working on IE plugIn and want to make visual style looks like real IE (background and mouseover effect). As I understand in your post you changed only background. Could you help me change mouseover event.
Hello Artyom,
Right, in this sample we change the background only. As for changing the mouseover behavior, we don’t have such code, I am sorry.