GNOME Builder is fast, clean & simple IDE for GTK application development (on Linux), integrated support for Git and easy possibility to publish the application on FlatHub. This is probably the best IDE for developing applications on Linux
Code::Blocks - Code::Blocks is a free C++ IDE built to meet the most demanding needs of its users.
Zenity - Zenity is a tool that allows you to display GTK dialog boxes in commandline and shell scripts.
Geany - Lightweight IDE for Linux and Windows
VisualWX - Visualwx aims to be the ultimate RAD tool, designed for c++, python, perl, ruby, lua and wxWidgets.
Yad - Yad (yet another dialog) is a fork of Zenity with many improvements, such as custom buttons...
Spacemacs - Community-driven Emacs distribution that meshes Emacs and Vim features.