--- title: Property Changed Callback in Slint — Slint Blog | daily.dev description: Slint 1.7 introduces an experimental `changed` callback feature for its property system, allowing developers to execute code when a property value changes. The... canonical: https://daily.dev/posts/property-changed-callback-in-slint-slint-blog-przjzxqaa twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Property Changed Callback in Slint — Slint Blog | daily.dev og:description: Slint 1.7 introduces an experimental `changed` callback feature for its property system, allowing developers to execute code when a property value changes. The... og:url: https://daily.dev/posts/property-changed-callback-in-slint-slint-blog-przjzxqaa og:image: https://api.daily.dev/og/posts/PrZjZxQAA.png og:image:alt: Property Changed Callback in Slint — Slint Blog og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Property Changed Callback in Slint — Slint Blog **[Slint](https://daily.dev/sources/slint)** · 5 min read · 0 upvotes · 0 comments ## Summary Slint 1.7 introduces an experimental `changed` callback feature for its property system, allowing developers to execute code when a property value changes. The post explains how Slint's lazy, reactive property bindings work, then details the new callback syntax and a practical SpinBox example. It also covers the design challenges: the callback forces eager evaluation, execution is deferred to the next event loop iteration to batch changes, and circular callback loops are capped at 10 chained changes per event loop as a runtime safeguard. The feature requires opting in via the `SLINT_ENABLE_EXPERIMENTAL_FEATURES=1` environment variable. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Similar posts on daily.dev - [Slint 1.18 Released](https://daily.dev/posts/slint-1-18-released-qsjr785iv) · Slint · 36 upvotes · 1 comments - [Slint 1.17 Released](https://daily.dev/posts/slint-1-17-released-no2jabrhd) · Slint · 1 upvotes · 0 comments - [Slint 1.16 Released](https://daily.dev/posts/slint-1-16-released-dfk6smuhp) · Slint · 0 upvotes · 0 comments - [Slint and the Node.js Event Loop](https://daily.dev/posts/slint-and-the-node-js-event-loop-3ayskjayl) · Slint · 78 upvotes · 1 comments --- Tags: [#rust](https://daily.dev/tags/rust) [View this post on daily.dev](https://daily.dev/posts/property-changed-callback-in-slint-slint-blog-przjzxqaa) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Property Changed Callback in Slint — Slint Blog","url":"https://daily.dev/posts/property-changed-callback-in-slint-slint-blog-przjzxqaa","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/property-changed-callback-in-slint-slint-blog-przjzxqaa"},"datePublished":"2026-07-12T07:19:48.300Z","dateModified":"2026-07-12T07:20:26.210Z","description":"Slint 1.7 introduces an experimental `changed` callback feature for its property system, allowing developers to execute code when a property value changes. 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