Pit Friedrich
85bb0c8c0b
The layout was saved to localStorage, but restoring it did not reliably reproduce it: - restore() applied the saved nodes one by one via grid.update(). A later item could collide with one already put back and push it off its saved spot, and nothing moved it back — so the restored layout was not the one the user left. Use grid.load(nodes, false) instead: it sorts the nodes, removes them from the engine before re-placing them, and runs in a single batch. addRemove is off because Flow owns which children exist. - gridstack's save() omits w/h when they are 1. The manual restore passed them through as undefined, and the server read them as 0 and wrote a zero-sized widget back onto the item. load() re-applies gridstack's own defaults; onLayoutChange now reads a missing w/h as 1. - A drag followed immediately by navigating to another route detached the element inside the 150ms persist debounce, dropping the pending save. disconnectedCallback now flushes it to localStorage first. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01Ue9ZtWUBQF4SuSHpzZ3zwq
My Application
A Spring Boot + Vaadin project. Build your UI in pure Java — no HTML, no JavaScript.
New to Vaadin? The 5-minute Quickstart walks you from here to your first running app, a live code change, and an AI-assisted edit with Copilot.
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From the project folder:
./mvnw spring-boot:run # Windows: mvnw.cmd spring-boot:run
Then open http://localhost:8080.
The first start takes ~30 seconds while Maven downloads dependencies.
Port 8080 already in use? Stop the other process, or set
server.port=8081insrc/main/resources/application.propertiesand open that port instead.To stop the app: press
Ctrl+Cin the terminal (or the red Stop button if you launched from your IDE).
Optional upgrade — instant hotswap
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- IntelliJ IDEA: install Vaadin from the JetBrains Marketplace → Debug using Hotswap Agent (dropdown next to Run). Just installed it? Let IntelliJ finish indexing, or restart it, if the menu item isn't there yet.
- VS Code: install the Vaadin extension → Vaadin: Debug using Hotswap Agent from the command palette.
- Eclipse: install the Vaadin plugin → right-click the project → Run As → Vaadin Application.
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./mvnw package
java -jar target/*.jar
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