How to change the size of a label or lineEdit in Qt-4.8.5-Designer?

  • In a ui-file form made and working for QGIS, I want to change the size of labels and lineEdits. In the right column of Qt-Designer, the values for geometry are grey and cannot be changed. All other values for other variables are black and can be altered. The geometry section seems not to be active. How can I make the geometry section active and change the values?