When you create a field in QT Designer, you can to assign an ID or name, then, when you load the ui file into a python class like
uic.loadUi(os.path.join(os.path.dirname(__file__), "customer.ui"), self)
the class load all fields from the ui file and you can to call like:
self.geometry.setText() = "something" #where self.geometry is the name of your ui field.
There is an other example:
class MainPage(QMainWindow):
def __init__(self):
super(MainPage, self).__init__()
uic.loadUi("SysMainUI.ui",self)
#self.minimizeBtn is a button into "SysMainUI.ui"
#self.minimizeBtn calls to "minimizar" function when clicked it
self.minimizeBtn.clicked.connect(self.minimizar)
self.maximizeBtn.clicked.connect(self.maximizar)
self.normalizeBtn.clicked.connect(self.normalizar)
self.closeBtn.clicked.connect(self.cerrar)