Qt Reference Documentation

Qt Designer's Editing Modes

Qt Designer provides four editing modes: Widget Editing Mode, Signals and Slots Editing Mode, Buddy Editing Mode and Tab Order Editing Mode. When working with Qt Designer, you will always be in one of these four modes. To switch between modes, simply select it from the Edit menu or the toolbar. The table below describes these modes in further detail.

Editing Modes
In Edit mode, we can change the appearance of the form, add layouts, and edit the properties of each widget. To switch to this mode, press F3. This is Qt Designer's default mode.
In Signals and Slots mode, we can connect widgets together using Qt's signals and slots mechanism. To switch to this mode, press F4.
In Buddy Editing Mode, buddy widgets can be assigned to label widgets to help them handle keyboard focus correctly.
In Tab Order Editing Mode, we can set the order in which widgets receive the keyboard focus.