Here you’ll find guided examples to get yourself familiarized with Gio.
If you are unsure where to start, then this is a pretty good place:
Writing an hello world.
Implementing an egg timer.
Different examples of Gio features.
We've all been there.
These documents provide a deeper look into Gio.
Writing a custom widget.
Gio from bottom-up.
Portable, Immediate Mode GUI Programs for Mobile and Desktop.
Demonstrating a Gio program built from scratch.
Discussions on Gio and project demos.
Most commonly used packages:
Stateful part of the widgets.
Drawing of the widget states.
Laying out the widget drawing
Low-level primitives of Gio.
Coloring the shapes.
Responding to mouse and touch events.
Responding to keyboard events.
Detecting common gestures.