Sprechen.c

A German learning application written in C using GTK 4.

Description

Sprechen.c is an educational program designed for practicing German language skills, aimed at high school and gymnasium students. The UI is available in Czech and English and is built as a single C file (sprechen.c) that renders a modern, CSS-styled GTK 4 interface.

Features

• Welcome screen – branded greeting with a description of the program and a continue button to get started
• Learning roadmap – adaptive serpentine learning path with 10 units
  • each unit numbered and labeled with its topic (e.g. "Neue Freunde")
  • units 1 and 2 are open; completed units shown in green with a checkmark
  • remaining units dimmed with a lock icon
  • finish node at the end of the path
  • layout folds into multiple rows when the window is narrow
• Back navigation – themed circular back button (top-left) returns to the previous screen
• Unit 1 exercises – "Neue Freunde" opens an interactive bubble map with 13 exercises (dialogs, sentence building, multiple choice, free answers, numbers, verb conjugation, greeting sorting and more), each with German prompts and a check button that reveals the translations
• Unit 2 exercises – "Aus aller Welt" is playable from the start (no need to finish unit 1 first) and offers a bubble map with 19 exercises: verb conjugation, prepositions aus/in, question words, nationalities and countries, spelling/look-and-find tasks, a matching exercise, a number/word game, free-answer "Steckbrief" tasks and a Hangman game with 5 professions
• Progress tracking – completed exercises are marked green; progress is saved per unit to progress/unit1.conf and progress/unit2.conf and restored on startup
• Settings – gear icon in the top-right header opens a panel where you can choose:
  • mode: dark or light, as a segmented control
  • theme: 10 palettes picked from a grid of color swatches
  • language: Czech or English, applied instantly without a restart
  • all three preferences are stored in progress/settings.conf
• Keyboard quit shortcuts – Super/Cmd+Q or Alt+F4 closes the app
• Single-file C codebase, cross-platform (Linux and macOS supported)

Installation

Prerequisites

1. GTK 4 development libraries

macOS:

brew install gtk4

Linux (Debian / Ubuntu):

sudo apt install libgtk-4-dev

Linux (Fedora):

sudo dnf install gtk4-devel

Linux (Arch):

sudo pacman -S gtk4

2. Build tools (compiler, Make, pkg-config)

macOS – install all of these explicitly, they are not preinstalled:

# installs the GNU C compiler, Make, and pkg-config
brew install gcc make pkg-config
# if you prefer Apple's Clang toolchain instead, you can run:
# xcode-select --install

Linux – no need to install gcc, it is already preinstalled on most distributions (it ships with build-essential/base-devel):

# Debian / Ubuntu: make sure you have the base toolchain and pkg-config
sudo apt install build-essential pkg-config

# Fedora
sudo dnf groupinstall "Development Tools"
sudo dnf install pkgconf-pkg-config

# Arch
sudo pacman -S base-devel pkgconf

Building the Application

1. Clone or download this repository
2. Navigate to the project directory
3. Build using the provided Makefile:

make

Or manually:

gcc -o sprechen sprechen.c `pkg-config --cflags --libs gtk4` -lm

Running the Application

make run

or

./sprechen

Usage

When launched, the application shows the welcome screen. From there:

1. Click "Pokračuj" / "Continue" to open the learning roadmap.
2. Browse the units along the path; the roadmap reflows into rows and scrolls if the window is too narrow.
3. Click the "Neue Freunde" node to open unit 1 or "Aus aller Welt" to open unit 2, then pick any bubble to start an exercise. Unit 2 is available even if unit 1 is not finished yet.
4. Use the back button in the top-left corner to return to the previous screen.
5. Open Nastavení / Settings (gear icon, top-right) to switch dark/light mode, pick a color theme, or change the interface language.

Units 1 and 2 are currently implemented. Locked units do nothing – they are placeholders until lessons are added. Completed exercises stay green and are saved per unit to progress/unit1.conf / progress/unit2.conf (created next to the app on first finish).

Keyboard shortcuts

Shortcut	Action
Super/Cmd + Q	Quit application
Alt + F4	Quit application

Project structure

sprechen.c              entire application (UI, navigation, themes, exercises)
Makefile                build & run targets
README.md               this file
LICENSE                 MIT license
progress/               created at runtime
  unit1.conf            unit 1 exercise completion state
  unit2.conf            unit 2 exercise completion state
  settings.conf         theme, dark/light mode and language preference

Theming

The app ships with ten palettes – Catppuccin, Nord, Dracula, Rose Pine, Ocean, Gruvbox, Solarized, Everforest, Monokai and One Dark – each available in dark and light mode. Colors are defined as theme palettes in sprechen.c and applied through a generated CSS stylesheet (plus matching Cairo colors for the roadmap rails and icons).

Change the look from the in-app settings panel, or edit the palette tables / build_theme_css() in sprechen.c and rebuild.

Languages

The interface can be switched between Czech and English from the settings panel; the choice takes effect immediately and is remembered between runs. Translations live in two tables in sprechen.c: tr_ui holds interface strings under short keys, while tr_content translates the Czech meanings shown next to the German exercise items and uses the Czech text itself as the key. Widgets are registered with i18n_bind() so apply_language() can retranslate them in place.

German prompts, unit names and exercise titles are learning material and stay German in both languages.

To-Do Plans

Future enhancements planned for Sprechen.c:

• Wire unit nodes to actual German vocabulary/grammar exercises
  • Unit 1 ("Neue Freunde") – 13 interactive exercises with progress saving
  • Unit 2 ("Aus aller Welt") – 19 interactive exercises (incl. Hangman)
• Lesson progression and unlock system for the remaining units
• Add audio pronunciation features
• Add user settings panel (theme, dark/light mode, language)
• Implement spaced repetition system for vocabulary
• Add listening and reading comprehension exercises
• Add writing practice with feedback
• Expand progress tracking with statistics
• Move CSS styling to an external file
• Split the UI code into multiple files
• Add internationalization support (Czech and English)
• Add more interface languages
• Add unit testing framework

License

This project is licensed under the MIT License - see the LICENSE file for details.

Acknowledgments

• Created as a learning exercise in C and GTK programming
• Inspired by language learning applications
• Built with GTK 4 for modern GUI development