guiCheckBoxChangeEvent (Function)

This function retrieves a check box changed event from the event queue, which is triggered when the user clicks on the check box.

This function must be called to clear event 2 from guiWaitEvent.

Input:

None.

Output:

check_box : SYSHANDLE

The handle to the check box.

checked : BOOL

The new state of the check box

Returns: INT

Declaration:

FUNCTION guiCheckBoxChangeEvent : INT;
VAR_INPUT
   check_box : ACCESS SYSHANDLE;
   checked   : ACCESS BOOL;
END_VAR;

Example:

...
FUNCTION CheckBoxHandler
VAR
   rc      : INT;
   handle  : SYSHANDLE;
   tag     : DINT := 0;
   checked : BOOL;
END_VAR;
   rc := guiCheckBoxChangeEvent(check_box := handle, checked := checked);
   IF rc = 0 THEN
      guiGetTag(handle := handle, tag := tag);
      IF checked THEN
         DebugFmt(message:="Check box with tag \4 was checked", v4 := tag);
      ELSE
         DebugFmt(message:="Check box with tag \4 was unchecked", v4 := tag);
      END_IF;
   END_IF;
END_FUNCTION;
...