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Topmost window wipes graphics of window below

I have a form that contains a panel with a gradient drawn in 2 colours. I have a call to the procedure that draws the gradient in the form paint and form resize events otherwise it gets wiped out. However, I have now noticed that when a new form is opened on top, as you move the new form around it wipes out the colour gradient drawn on the form below just like a photoshop eraser tool. How can I stop this happening, do I have to start calling the gradient drawing procedure from the new form or is there another event in the original form that I need to put the call in. Hopefully ther latter, or having a gradient is going to be more trouble than its worth! Any help appreciated.

SOLUTION

Jayadev Nair

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ASKER CERTIFIED SOLUTION

Fernando Soto

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JeffvClayton

ASKER

Thanks for the reply compued, I have tried that out and it works fine (with a bit of flicker on the painted text on top of the gradient)

Fernando, I get a syntax error with the word imports. However, here is the code I have used (in a module) which is now called by form resize,paint,load, and panel paint. I am using VB.Net 2003. To me it looks like it basically does the same thing so I don't understand why it would be persistant!

Public Sub DrawGradient(ByVal pan As System.Windows.Forms.Control, ByVal color1 As Color, ByVal color2 As Color, ByVal mode As System.Drawing.Drawing2D.LinearGradientMode)

If pan.Width > 0 And pan.Height > 0 Then

Dim a As New System.Drawing.Drawing2D.LinearGradientBrush(New RectangleF(0, 0, pan.Width, pan.Height), color1, color2, mode)
Dim g As Graphics = pan.CreateGraphics

g.FillRectangle(a, New RectangleF(0, 0, pan.Width, pan.Height))

Dim myBrush As New SolidBrush(Color.White)
pan.CreateGraphics.DrawString("Company Name", pan.Font, myBrush, pan.Width - 200, 10)
g.Dispose()

End If

End Sub

JeffvClayton

ASKER

Here is how I call the above

DrawGradienC(Me.Panel1, Color.Gainsboro, Color.SteelBlue, Drawing.Drawing2D.LinearGradientMode.Horizontal)

Fernando Soto

My code is persistant because I create an image and then assign that image to the Panel1.BackgroundImage = gradientImage. In doing this the system will handle the painting no need to execute the code again, no flicker.

The Imports statement should not give a syntax error unless you do not have a reference to System.Drawing or System.Drawing.Drawing2D.

Fernando

JeffvClayton

ASKER

Thanks to both of you for giving 2 ways to solve the problem.

I have gone with the solution from Fernando for most of the points as I only need to draw the graphics once i.e. the graphics are persistant. I solved the Imports syntax error by putting the imports statements above the following lines

Imports System.Drawing
Imports System.Drawing.Drawing2D

Public Class Form3
Inherits System.Windows.Forms.Form

Thanks for the help.

Regards

Jeff.

Fernando Soto

Glad I was able to help. ;=)

Jayadev Nair

ThanX Jeff