code: def _populate_coordinates(self):
          
          rect = self.tool.rectangle()
          self.blockSignals(True)
          if not rect.isEmpty():
              self.x_minimum.setValue(rect.xMinimum())
              self.y_minimum.setValue(rect.yMinimum())
              self.x_maximum.setValue(rect.xMaximum())
              self.y_maximum.setValue(rect.yMaximum())
          else:
              self.x_minimum.clear()
              self.y_minimum.clear()
              self.x_maximum.clear()
              self.y_maximum.clear()
          self.blockSignals(False)
docs: Update the UI with the current active coordinates.