System Integration: Clipboard, Commands & Notifications | Kotlin Desktop #18

Learn JVM system APIs in Kotlin Compose Desktop! We build a System Toolbox with three tabs — Clipboard History that monitors your clipboard in real-time, a Command Runner that executes shell commands with ProcessBuilder, and System Info showing platform details and environment variables. Uses NavigationRail for tab navigation and Compose Desktop Tray for native notifications. What You'll Learn: - Clipboard monitoring with AWT Toolkit.getDefaultToolkit().systemClipboard - Coroutine-based polling with delay() (more reliable than FlavorListener on macOS) - Reading clipboard with DataFlavor.stringFlavor and writing with StringSelection - Shell command execution via ProcessBuilder("/bin/sh", "-c", command) - Process timeout handling with waitFor() and destroyForcibly() - NavigationRail for vertical tab navigation with Material icons - Tray composable with rememberTrayState() for system tray integration - Desktop notifications via sendNotification() on clipboard and command events - System.getProperty() for OS/arch/Java version and System.getenv() for environment variables - derivedStateOf for efficient filtering of environment variable lists Timestamps: 0:00 - Introduction 0:15 - Preview: System Toolbox App 0:45 - Project Setup & Data Models 3:32 - Clipboard Manager (AWT Polling) 5:03 - Command Runner (ProcessBuilder) 6:28 - UI Tabs (Clipboard, Command, System) 17:00 - AppContent (NavigationRail) + Main (Tray) 22:06 - Live Demo: System Toolbox 23:20 - Recap & Key Takeaways 24:20 - Thanks for Watching Key Takeaways: 1. Clipboard Access — Toolkit.getDefaultToolkit().systemClipboard reads and writes with DataFlavor.stringFlavor 2. Polling Pattern — Coroutine-based polling with delay() is more reliable than FlavorListener on macOS 3. Process Execution — ProcessBuilder("/bin/sh", "-c", command) runs shell commands with waitFor() timeout 4. System Notifications — Tray composable with rememberTrayState() and sendNotification() for desktop alerts 5. Platform Detection — System.getProperty("os.name") and System.getenv() for system information Previous Lesson: Lesson 17: Rich Text & Markdown — Markdown Editor with Live Preview https://youtube.com/... Next Lesson: Lesson 19: (coming soon) Tech Stack: Kotlin 2.1, Compose Multiplatform 1.7.3, Material3 Material Icons Extended, JVM Standard Library (AWT, ProcessBuilder) Gradle 8.10, JVM 17+ Source Code: https://github.com/GoCelesteAI/kotlin_desktop_system_toolbox Taught by CelesteAI If you found this helpful, please like and subscribe for more Kotlin Desktop tutorials! #kotlin #compose #desktop #material3 #clipboard #processbuilder #systemtray #notifications #navigationrail #jvm #tutorial #programming