If you need to position an object so that it remains its natural size, but floats centered in an area, you can use dSizers and spacers to achieve this.
For example, let's say that you want a label centered horizontally on a form. You'd first create a horizontal sizer, and then add the label surrounded by spacers. The trick is to give the spacers proportions of 1 and the label a proportion of 0. Here's what the code would look like, assuming that self is the form:
lbl = dabo.ui.dLabel(self, Caption="I'm in the middle!")
sz = dabo.ui.dSizer("h")
sz.appendSpacer(1, proportion=1)
sz.append(lbl, proportion=0)
sz.appendSpacer(1, proportion=1)
self.Sizer.append(sz)
self.layout()
Another option, assuming that you have a single vertical sizer for the form, is to add the label, being sure to set the halign parameter when adding to the sizer:
lbl = dabo.ui.dLabel(self, Caption="I'm in the middle!")
self.Sizer.append(lbl, halign="center")
self.layout()