I have a database with a form and a subform. Both forms contain the same
dataset, the mainform contains a tablegrid and the subform contains the seperate
textfields. There's two actions I want to do: edit a record and add a record.

Edit a record:
If I open the form I first have to click on a record in the tablecontrol and
then switch to the fields to be able to get the save-button to appear. This
means some extra clicks which is not "natural" behaviour. If however I call a
macro with a messagebox from a "button pushed" or "when form loading" event is
seems like the subform is initialized or something like that, after this the
subform works as expected. If omitting the messagebox from the macro, the
behaviour disappears.

Add a record:
Roughly the same steps have to be taken when adding a record. If I simply click
add, I'm not able to enter information in the fields. I first have to click on
the tablegrid then have to click on a field in the subform before I'm able to
add a new record. If however I call the macro with a messagebox first,
everything works as expected.