Making A FlowLayoutPanel have a transparent background

Question

I have a button that dynamically adds up to 24 labels to the form. The problem is their location.

I figured out that instead of manually setting a specific location for each, I can have them automatically arranged like a FlowLayoutPanel does. But the FLP will be on top and hide controls under it. And sending it to back is worse. So i want to bring it to front but keep it transparent, so that it doesn't hide the other controls under it.

Any suggestions will be great

Thanks.

A `FlowLayoutPanel` is not magic. When you use one, you don't have to specify the `Location` of each child control because it contains the code to calculate them itself. If you're using a `Panel` then there is no such code contained within it so you have to calculate them yourself. There's no way around that. You could inherit `Panel` and encapsulate that code, but you still have to write the code, one way or another. — jmcilhinney, Jan 05 '17 at 04:10
@ jmcilhinney - Ok I will edit my post and make things more clear. (Way more clear...) — TGamer, Jan 05 '17 at 12:04
So, are you saying that you want the `Labels` to appear in front of the image? Have you considered using a `FlowLayoutPanel` and setting its `BackgroundImage`? I've never tried it myself with that control but I would think that it should work. — jmcilhinney, Jan 05 '17 at 12:36
No that doesn't, because each picturebox can be panned inside its pannel. I can't make it a simple background image. Also, the the `pic`'s can be zoomed in or out. It looks like I have to either make them all at one place or code their locations one by one. — TGamer, Jan 05 '17 at 21:27

score 3 · Accepted Answer · edited May 23 '17 at 12:34

I can have them automatically arranged like a FlowLayoutPanel does. But I can't use one because it will be on top and hide the images in my pic's.

Well, you can use a FlowLayoutPanel with a transparent background so it doesn't hide the other controls you have. How to do that? Well, this answer shows you how to make a transparent Panel. You should be able to easily adjust it to work with a FlowLayoutPanel using something like this:

Public Class TransparentFLP
    Inherits FlowLayoutPanel

    Protected Overrides ReadOnly Property CreateParams() As System.Windows.Forms.CreateParams
        Get
            Dim cp As CreateParams = MyBase.CreateParams
            cp.ExStyle = cp.ExStyle Or &H20 ''#WS_EX_TRANSPARENT
            Return cp
        End Get
    End Property
    Protected Overrides Sub OnPaintBackground(ByVal e As System.Windows.Forms.PaintEventArgs)
        ''#MyBase.OnPaintBackground(e) --> Don't uncomment this orelse
                                          'it will cause the BackColor to be redrawn.
    End Sub

End Class

Add a new Class to your project.
Paste the above code into it.
Rebuild your project.
Drop the new control from the top of the toolbox onto your form (instead of using the original FlowLayoutPanel).
You're good to go.

P.S. I'm not sure about the use of your 4 panels, but you might consider using a TableLayoutPanel instead.

Hope that helps :)

So you're saying I have make my project again? by copy+paste? Why can't I just add your code to mine? — TGamer, Jan 08 '17 at 11:34
@TGamer, I didn't say make a new project. I said "Add a new Class to your project". Project menu --> Add Class. — 41686d6564 stands w. Palestine, Jan 08 '17 at 19:29
I get it. But what about my `FlowLayoutPanel`'s name property? — TGamer, Jan 09 '17 at 07:31
@TGamer, you'll need to delete the existing `FlowLayoutPanel`, use the new `TransparentFLP` instead (which you can name it whatever you want). Hope that's clear :) — 41686d6564 stands w. Palestine, Jan 09 '17 at 07:33

Making A FlowLayoutPanel have a transparent background

1 Answers1