Constructor event
Description
Occurs when the control or object is created, just before
the Open event for the window that contains the control.
Event ID
|
Event ID |
Objects |
|---|---|
|
pbm_constructor |
All objects |
Parameters
None
Return Values
Long. Return code choices (specify in
a RETURN statement):
-
0 Continue
processing
Usage
You can write a script for a control’s Constructor
event to affect the control’s properties before the window
is displayed.
When a window or user object opens, a Constructor event for
each control in the window or user object occurs. The order of controls
in a window’s Control property (which is an array) determines
the order in which Constructor events are triggered. If one of the
controls in the window is a user object, the Constructor events
of all the controls in the user object occur before the Constructor
event for the next control in the window.
When you call OpenUserObject to add a user
object to a window dynamically, its Constructor event and the Constructor
events for all of its controls occur.
When you use the CREATE statement to instantiate
a class (nonvisual) user object, its Constructor event occurs.
When a class user object variable has an Autoinstantiate setting
of true, its Constructor event occurs when the
variable comes into scope. Therefore, the Constructor event occurs
for:
-
Global variables when
the system starts up -
Shared variables when the object with the shared
variables is loaded -
Instance variables when the object with the instance
variables is created -
Local variables when the function that declares
them begins executing
Examples
This example retrieves data for the DataWindow dw_1 before
its window is displayed:
|
1 |
dw_1.SetTransObject(SQLCA) |
|
1 |
dw_1.Retrieve( ) |