GTKKit is a multithreaded MVC GUI framework, which implements a UIKit-style Objective-C API on top of the GTK+ cross-platform widget toolkit. It is under active development, and it currently in a barely usable, skeletal state. GTKKit is inspired by UIKit, but is not a clone of it, nor is it intended to be compatible with it. It is intended to give experienced Cocoa/iOS developers a comfortable, familiar environment to develop cross-platform applications, and to introduce concepts from the Cocoa/iOS world to developers for other platforms. Requirements: - GTK+ 3 - ObjFW (https://webkeks.org/objfw/) - Doxygen (optional, for generating API documentation) At the moment, GTKKit is only tested on OS X and FreeBSD. Currently, GTKKit implements the following class hierarchy: OFObject [part of ObjFW] GTKCoder GTKKeyedArchiver GTKKeyedUnarchiver GTKResponder GTKApplication GTKPopover GTKView GTKActionBar GTKBox GTKControl GTKButton GTKInfoBar GTKPopUpButton GTKComboBox GTKSegmentedControl GTKSlider GTKTextField GTKImageView GTKLevelIndicator GTKListView GTKProgressIndicator GTKSeparator GTKSplitView GTKStatusbar GTKTabView GTKWindow GTKTabbedWindow GTKOffscreenRenderingWindow GTKImage GTKEvent GTKDispatchQueue GTKLayoutConstraint GTKLayoutConstraints GTKTab