Runtime Controls

[martialarts]

My program reads from a data file and outputs a series of controls for each line in the text file. I am using .NET 2002 and from what I can gather, control collections are no longer built in. I am trying to dynamically create and dynamically name these controls. I was able to integrate this code into my program and it works partially:

 

'this is part of a loop and counter is incremented each time

'element is an instance of a class

Dim LabelA1 As New Label()

LabelA1.Width = 232

LabelA1.Height = 24

LabelA1.Location = New Point(16, counter * 25)

LabelA1.Text = element.name

Me.Controls.Add(LabelA1)

LabelA1.Name = "LabelA" & counter

 

I don't know if I'm on the right track, but it does display all the controls like I need it to when I run it. The problem is that all the labels are named "LabelA1", and my attempts to manipulate any one of them are treated aggregately. I guess this is because their name was "LabelA1" when added to me.controls. Please point me in the right direction. I am new to VB and .NET, but not to programming in general. Thanks!

[mutant]

You could use the array list to keep the control in a collection.

[Robby]

Why are they all named LabelA1, is your Counter incrementing ?

[martialarts]

Thank you both for responding, especially so quickly. I implemented mutant's solution and it worked... although it led me to another question. I don't know if I completely understand control collections yet, but to answer Robby's question- I intended for it to increment so that I could individually reference each of them with LabelA1,LabelA2, LabelB1,LabelB2... where LabelAx was the first column of labels and LabelBx was the second column, etc. I couldn't implement that correctly because the syntax to add to a collection is:

 

me.controls.add(LabelA1)

 

which doesn't allow me to dynamically name the labels with variables... I don't know if there is an alternate syntax that would work better for me...

 

me.controls.add("LabelA" & x)

 

would be nice, but .net doesn't seem to work that way. Anyway, by using the control collection references I can awkwardly manipulte individual controls, but I don't know of a way to use a gotfocus event to change the background of my text boxes since they are also dynamically generated. Do you know how to do this? Thanks again for your time!

[mutant]

Im not sure if im understanding you right :) , but I thinnk you are in need of an event handler. To add one dynamically do this:

AddHandler ControlName(counterorwhateveryouuse).GotFocus, AddressOf handlersub

Your handler sub must accept arguments that correspond to the event. Then you check what control sent it with the sender argument.

 

Again, I might totally off on this, so tell me if im talking about what you wanted to know :) .

[Robby]

If all you want is to add controls at runtime...

For x = 1 To 20
 txt = New textbox()
 With txt
   AddHandler .GotFocus, AddressOf txtClick
   .Text = "Textbox " & x.tostring
   .Location = New Point(0, x * 25)
   .Size = New Size(200, 60)
 End With
 Controls.Add(txt)
Next

[martialarts]

Thanks again. I used your advice and it worked! I took it a couple of steps farther to make sure that I could do everything I needed to do. I am finally able to address my dynamic controls individually, although I have to do by searching through the controls array to find them... which isn't a problem at all. I'm surprised and also greatful that both of you are so active on this forum. If I become experienced at VB I will be sure to check this forum for people I can pass the favor on to. Thanks!