w3af can not work after all dependencies demanded being installed

After I installed all the dependencies in demand, I tried to run

./w3af_gui

but this error message appeared:

The GTK package requirements are not met, please make sure your system meets these requirements:
- PyGTK >= 2.12
- GTK >= 2.12
The required "dot" binary is missing, please install the "graphviz" package in your operating system.

For now, I don't know how to proceed. Is there anyone can help, appreciate much.