How to handle the messages for controls which created at run time?

How to handle the messages for controls which created at run time?

(Include windows stardard control and ActiveX control)

Hi,


I guess, you mean 'events' raised from the controls?

Only way as i know is to have a member variable of the same type and use set

method when you create a run-time instance. The varibale should have a module-level (global) scope.


Ex: Suppose you have a control, StateChangingControl ,that raises some StateChanged(NewState,OldState) event.


To be able to handle this event you need something like this:


In the declaration section of Form/Class have a line:

private WithEvents m_mycontrol as StateChangingControl


and when you create a new runtime instance use:

...

set m_mycontrol = new StateChangingControl

...


With 'WithEvents' command, if VB detects any events associated with this StateChangingControl , it automatically lists them in the methods combobox.

You should see the member 'm_mycontrol' in the controls (LHS) combo (on the Editor)and when you select this, you should see the event 'StateChanged' in the methods (RHS) combo . And when you select 'StateChanged' from this list,

VB will create a stub like:


private sub m_mycontrol_StateChanged(NewState,OldState)

end sub

and the respective types of the params would also be present.


Try a simple code :

private withevents m_mytimer as Timer

and it would work like a timer-control of VB


I hope it was not a long answer for a not-required topic! :-)


Ravi