Open Source Linux User Interface (UI) Software - Page 55

Fast UML is an open-source UML tool with a simple user interface pop-up free. Draw UML diagrams fast, export diagrams to png, jpg and clipboard. It pretends to be the union between Violet and UMLet.

Fenster is a minimal, highly opinionated library for creating cross-platform 2D graphical applications. Its core implementation is a single C99 header of roughly 300 lines, making the code easy to inspect and modify. It opens one titled window and exposes a simple 24-bit RGB framebuffer for direct pixel drawing. Keyboard events, mouse coordinates, clicks, timing, application lifecycle, and system events are handled through a polling API. The same interface also provides audio playback through WinMM on Windows, CoreAudio on macOS, and ALSA on Linux. Programs do not need callbacks, multithreading, or a large GUI framework. Fenster additionally offers Go, Zig, and community Lua bindings and is capable enough to support games, visual experiments, and even Doom ports.

"Fiber" is a java library which adds functionalities to the Sun java standard library : new Swing widgets ( preferences dialog, event log , ... ) , new supported protocols ( rss ) , frameworks ( user tracking on web applications ) and other utilities

This project aims to develop a new GUI design experience with platform independent "Look and Feel". The aim of a this project is to develop a java library which shall be able to use with any type of software developed in java.

A series of projects used for Flagrun Networks (http://www.flagrun.net) this network is dedicated to hosting; open source projects, development websites, gaming mods, community sites. these are the tools used on flagrun, completely open source to the pub

OpenSource 3D Engine for Flash MX 2004: Create 3D applications using the builtin DataCube object and put your data as dynamic 3D Models into a virtual universe. Then let the viewer navigate the camera interactively through your data universe.

Macromedia Flash ActiveBpel process viewer. Processes can be shown, flow and view of variables used to invoke webservices.

Flex Smiley Text Area is a flex component allowing you to use emoticons such as :-) and :-P in the text area, which are converted to swf animated icons. This functionality does not work correctly in the flex text component - so FSTA puts that right :-D

With FlexMT each flex program can be easily equipped with multi-touch operation. FlexMT supports symbolic and direct gestures like dragging, rotating or scaling and uses TUIO for touch detection. FlexMT is part of a Tabletop-Project at the FH-Trier.

FlexViz is a graph-based visualization tool written entirely in Flex and ActionScript 3.0. It is based on the Shrimp/Jambalaya/Creole java tools and has the same layouts that have been ported from Java into ActionScript.

FlexiSense is a free GUI library, for the creation of user interfaces for games or other applications. The library is object orientated, written in C++, cross-platform and free renderer, provides transition and motion effects. Is support themes.

Flexible ConFiguration LIBrary is a small, simple, flexible and portable ANSI C Library to be used as configuration interface for user programs. It maintains a compact parameters list fed from various sources providing simple access and other goodies.

Float UI is an open-source collection of modern UI components and website templates built primarily for React, with planned support for Vue, designed to help developers rapidly build visually polished and responsive web applications. It combines Tailwind CSS with carefully crafted design patterns to deliver components that are both aesthetically appealing and production-ready. The project includes a wide variety of reusable UI elements and complete templates, such as landing pages, dashboards, and navigation layouts, allowing developers to bootstrap projects quickly. One of its strengths is its focus on simplicity and accessibility, providing ready-made solutions that can be easily customized without complex configuration. Float UI supports both left-to-right and right-to-left layouts, making it suitable for international applications. It is actively maintained and continuously expanded, with new components and templates added over time.

A PHP web application framework centered around a page/control/rpc server model with a framework for modules and permissions. Support for OpenID/Facebook Connect included. All data is persisted in a JSON object store, so no SQL server is required.

Fluid is an adaptative framework for model-driven development. Based on the Eclipse environment, Fluid defines model transformations among several modeling technologies and engines, as well as multi-tier application architecture definitions.

This is a responsive admin/dashboard UI template built in Flutter. It is designed to work across platforms (web, desktop, mobile) and offers prebuilt UI elements (charts, tables, cards, etc.) so developers can use it as a backend UI scaffold.

flutter_ui_challenges is a collection of Flutter UI designs and implementations showcasing various layouts, patterns, and widget usages. It serves as a playground and reference for developers wanting to learn how to replicate complex mobile UI elements in Flutter. The repository includes dozens of screens like onboarding flows, e-commerce pages, profiles, dashboards, and animated components. Each example demonstrates how to combine core Flutter widgets with creative styling and transitions to achieve polished results. It’s particularly valuable for beginners who want to see hands-on approaches to real-world UI problems. The project doubles as inspiration and a teaching resource, with each implementation structured clearly for experimentation and modification.

flutter-ui-nice is a collection of Flutter UI examples and clones that replicate popular mobile app designs. It includes sample implementations of login screens, shopping flows, media apps, dashboards, and social layouts. The goal is to give developers a reference for how to achieve common UI patterns using Flutter widgets and theming. Each example is designed to be clean, responsive, and easy to adapt into production codebases. The repository is particularly helpful for beginners who want hands-on guidance on structuring real screens instead of only isolated widgets. It serves as both a design gallery and a practical teaching tool, showing how Flutter can mimic polished, industry-level designs.

YALFoldingTabBar is a subclass of a standard UIView. We wanted to make this component expand and contract in response to a user tapping. When the component is closed you can only see a central button (“+”). When tapping on it, our custom Tab Bar expands letting other tabBarItems appear, so that the user can switch the controllers. YALFoldingTabBarController is a subclass of UITabBarController with custom animating YALFoldingTabBar. Each separate tabBarItem can have two additional buttons on the left and right. These buttons can be used to let a user interact with a selected screen on the YALFoldingTabBarController without even having to leave it.

Sample Food Truck is a comprehensive Swift sample app that demonstrates modern Apple platform patterns across data modeling, UI, and system integrations. It showcases SwiftUI-first architecture with navigation, lists, detail flows, and state management suitable for iPhone, iPad, and Mac. The project models a small business scenario—menus, orders, inventory, and analytics—so you can see realistic domain logic rather than a toy counter. It integrates with platform frameworks like Charts, widgets, and notifications to highlight how to surface insights and re-engage users. The code emphasizes testability and separation of concerns, illustrating how to structure features and preview them with sample data. For teams adopting SwiftUI at scale, it serves as a guided reference that balances clean architecture with platform-native polish.

This is a universal interface for various functions and programs, mathematical or any others.

FusionEdit is an open source collaborative IDE designed for the FIRST Robotics competition.

Theme switcher tool for the jQuery UI CSS Framework. Change the css stylesheet using an jQuery UI dialogbox which you can call using a button or a link in your html page. Completely implemented in your webspace.