creating addhandlers for runtime created labels

[lukisf]

I am currently working on my thesis and i came up with a problem. basically, my thesis is a simulation of an arena where you can change the positioning (by dragging) of the seating etc. Now i used labels as seats. I'm attaching the code i used to enable dragging

[LEFT][COLOR=#0000ff]Dim[/COLOR] dragging [COLOR=#0000ff]As[/COLOR] [COLOR=#0000ff]Boolean[/COLOR][COLOR=#0000ff]Dim[/COLOR] startx, starty [COLOR=#0000ff]As[/COLOR] [COLOR=#0000ff]Integer[/COLOR][COLOR=#0000ff]Private[/COLOR] [COLOR=#0000ff]Sub[/COLOR] [/LEFT]
 
[LEFT]Form1_Load([COLOR=#0000ff]ByVal[/COLOR] sender [COLOR=#0000ff]As[/COLOR] System.Object, [COLOR=#0000ff]ByVal[/COLOR] e [COLOR=#0000ff]As[/COLOR] System.EventArgs) [COLOR=#0000ff]Handles[/COLOR] [COLOR=#0000ff]MyBase[/COLOR].Load[/LEFT]
 
[LEFT][COLOR=#0000ff]End[/COLOR] [COLOR=#0000ff]Sub[/COLOR] [/LEFT]
 
[LEFT][COLOR=#0000ff]Private[/COLOR] [COLOR=#0000ff]Sub[/COLOR] lblseat_MouseDown([COLOR=#0000ff]ByVal[/COLOR] sender [COLOR=#0000ff]As[/COLOR] [COLOR=#0000ff]Object[/COLOR], [COLOR=#0000ff]ByVal[/COLOR] e [COLOR=#0000ff]As[/COLOR] System.Windows.Forms.MouseEventArgs) [COLOR=#0000ff]Handles[/COLOR] lblseat.MouseDown[/LEFT]
 
[LEFT]dragging = [COLOR=#0000ff]True[/COLOR]
startx = e.X
starty = e.Y
[COLOR=#0000ff]End[/COLOR] Sub[/LEFT]
 
[LEFT][COLOR=#0000ff]Private[/COLOR] [COLOR=#0000ff]Sub[/COLOR] lblseat_MouseMove([COLOR=#0000ff]ByVal[/COLOR] sender [COLOR=#0000ff]As[/COLOR] [COLOR=#0000ff]Object[/COLOR], [COLOR=#0000ff]ByVal[/COLOR] e [COLOR=#0000ff]As[/COLOR] System.Windows.Forms.MouseEventArgs) [COLOR=#0000ff]Handles[/COLOR] lblseat.MouseMove[/LEFT]
 
[LEFT][COLOR=#0000ff]If[/COLOR] dragging = [COLOR=#0000ff]True[/COLOR] [COLOR=#0000ff]Then[/COLOR]
lblseat.Left = (lblseat.Left + e.X) - startx
lblseat.Top = (lblseat.Top + e.Y) - starty
[COLOR=#0000ff]End[/COLOR] [COLOR=#0000ff]If[/COLOR][/LEFT]
 
[LEFT][COLOR=#0000ff]End[/COLOR] [COLOR=#0000ff]Sub[/COLOR] [/LEFT]
 
[LEFT][COLOR=#0000ff]Private[/COLOR] [COLOR=#0000ff]Sub[/COLOR] lblseat_MouseUp([COLOR=#0000ff]ByVal[/COLOR] sender [COLOR=#0000ff]As[/COLOR] [COLOR=#0000ff]Object[/COLOR], [COLOR=#0000ff]ByVal[/COLOR] e [COLOR=#0000ff]As[/COLOR] System.Windows.Forms.MouseEventArgs) [COLOR=#0000ff]Handles[/COLOR] lblseat.MouseUp[/LEFT]
 
[LEFT]dragging = [COLOR=#0000ff]False[/COLOR][/LEFT]
 
[LEFT][COLOR=#0000ff]End[/COLOR] [COLOR=#0000ff]Sub[/COLOR][/LEFT]

Now i need to create labels during runtime. I know how to do that with the me.labels.add(variable).
I need help with assigning the dragging mode to the labels. I presume i have to use addhandler but i have no idea with regards to coding....

any help very much appreciated.

thanks
Luke

 

[JohnH]

dim l as new label
addhandler l.mousedown, addressof lblseat_MouseDown

Here is an alternative approach where you can drag any control on form without using any of the controls event handlers, all done with only the keydown and mousemove events of the form: http://www.vbdotnetforums.com/showthread.php?t=16935 (post 4)

 

[lukisf]

but if i do this, when i click on the new button and move it, the lblSeat moves not the new button.

 

[JohnH]

In the event handler the 'sender' parameter (Object) is the control that raised the event. Event handler:

Dim l As Label = DirectCast(sender, Label)