How do I make programmatically generated labels transparent to each other VB.NET

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Hello,

I want to make an application where the user can draw an electric installation of a building. My plan to do so is generating a label when an electric part is selected.
This label is generated inside a panel, but when i generate two labels for example, they overlap instead of being transparent to each other. Is there a way to make those generated labels transparent to each other?

Here is my code for generating a label with a buttonclick:
(the code is running in vb.net)

Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        Dim lbl As New Label With {
            .Visible = True,
            .Text = (++lblNum).ToString(),
            .AutoSize = True,
            .Font = New Font(System.Drawing.FontStyle.Bold, 15)
        }
        'lbl.BackColor = Color.Transparent --> doesn't work
        Panel2.Controls.Add(lbl)

        AddHandler lbl.MouseDown, AddressOf LabelMouseDown
        AddHandler lbl.MouseMove, AddressOf LabelMouseMove
        AddHandler lbl.MouseUp, AddressOf LabelMouseUp

        lblNum = lblNum + 1

    End Sub

Thanks in advance.

Greetings,
Rudy

What I have tried:

I tried to make the background of the label transparent but that doesn't seem to work. Also when I searched for the problem, I came across the method to make a picturebox as a parent of the label. I tried this mechanic with the label itself, but obviously a control can't be a parent of itself.

Posted 5-Apr-18 21:15pm

TheRuudster

Updated 5-Apr-18 21:47pm

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This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Maciej Los · Accepted Answer · 2018-04-05T21:48:00

Quote:
By default, controls do not support transparent backcolors. However, you can allow your control to have a background color that is opaque, transparent, or partially transparent by using the SetStyle method[^] in the constructor. The SetStyle method of the Control class allows you to set particular style preferences for your controls, and can be used to enable or disable support for transparent backcolors.
NoteNote

Note:
Windows Forms controls do not support true transparency. The background of a transparent Windows Forms control is painted by its parent.

To give your control a transparent backcolor

Locate the constructor for your control class. The constructor appears in the control's code file. In C#, the constructor is the method with the same name as the control and with no return value. In Visual Basic, the constructor is the method named New.

Call the SetStyle method of your form in the constructor

VB
SetStyle(ControlStyles.SupportsTransparentBackColor, True)

Source: How to: Give Your Control a Transparent Background[^]

[EDIT]
Due to SetStyle accessibility (protected method[^]), the only way to create transparent Control (in this case Label) is to create custom class which derives[^] from Control (or Label), for example:

Public Class TransparentLabel
	Inherits Label
		
	Public Sub New
		Me.ForeColor = Color.Green
		Me.BorderStyle = 1 'Solid. The border is centered on the edge of the shape.
		Me.SetStyle(ControlStyles.SupportsTransparentBackColor, True)
	End Sub
 
End Class

Then, you have to create custom controls in code:

VB

Dim tl As TransparentLabel = New TransparentLabel()
With tl
    .Location = New System.Drawing.Point(10, 10)
    .Parent = Me 'Form
   'Set other properties here
End With

Note: not tested (haven't enough time).

How do I make programmatically generated labels transparent to each other VB.NET

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How do I make programmatically generated labels transparent to each other VB.NET

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