Layout Inspector & Recomposition Counts
Measure recompositions with real tools.
Layout Inspector & Recomposition Counts is a free Jetpack Compose Academy lesson on CoddyKit — lesson 4 of 4. You can read the complete lesson below for free — then practise it hands-on in the browser with a built-in code editor and a 24/7 AI tutor. It is part of the Jetpack Compose Academy learning path, one of 4 lessons in the course, and your progress syncs across the web and the CoddyKit app.
Measure, Do Not Guess
Performance tuning starts with data. Android Studio shows exactly which Composables recompose and how often, so you fix real problems.
Open Layout Inspector
The Layout Inspector attaches to a running app and renders a live tree of every Composable currently on screen.
Recomposition Counts Column
Enable the recomposition counter to see two numbers per node: total recompositions and how many of those were skipped.
High Counts Are Red Flags
A node recomposing hundreds of times while you barely interact is a hotspot worth investigating for unstable inputs.
Skip Count Tells the Story
A healthy Composable shows many skips. Zero skips next to a high recomposition count means stability is broken somewhere.
Reset the Counters
You can reset the counts, perform one action, then read the deltas. Isolating a single interaction makes the data easy to read.
Compose Compiler Reports
The compiler metrics report lists every Composable as restartable, skippable, or not, plus why each parameter is unstable.
Find the Unstable Class
The reports name the exact class Compose sees as unstable, pointing you straight at the type that needs val or an annotation.
Layout Inspector Plus Reports
Use the inspector to spot a hotspot, then the compiler report to learn why it cannot skip. Together they close the loop.
Profile a Release-Like Build
Measure performance on a release build, not debug. Debug Compose runs extra checks that distort real recomposition timing.
Tune, Then Re-Measure
After a fix, re-run the inspector to confirm skips went up. Always verify the change with numbers before moving on.
Quick Check
Check your tooling knowledge.
Recap: Let Tools Lead
Use Layout Inspector counts and compiler reports to find real hotspots, fix the unstable cause, then re-measure to prove it. ✅
Frequently asked questions
Is the “Layout Inspector & Recomposition Counts” lesson free?
Yes — the full text of “Layout Inspector & Recomposition Counts” is free to read here on the web, and the Jetpack Compose Academy course includes 4 lessons in total. To practise it interactively (a built-in code editor and a 24/7 AI tutor) and unlock the rest of the Jetpack Compose Academy course, upgrade to CoddyKit PRO.
What will I learn in “Layout Inspector & Recomposition Counts”?
Measure recompositions with real tools. You practise Jetpack Compose Academy with hands-on code you run directly in the browser, and a 24/7 AI tutor answers your questions as you work through the lesson.
Do I need any experience to start Jetpack Compose Academy?
No prior experience is required. Jetpack Compose Academy on CoddyKit is structured for beginners through advanced learners; this is — lesson 4 of 4, so you can start here or from the beginning and move at your own pace.
How long does the “Layout Inspector & Recomposition Counts” lesson take?
Most CoddyKit lessons take about 5–10 minutes. Each one is bite-sized and interactive, so you make steady progress and pick up exactly where you left off across the web and the app.
Can I write and run code in this Jetpack Compose Academy lesson?
Yes. Every Jetpack Compose Academy lesson includes a built-in code editor, so you write and run real code right in your browser and get instant AI feedback — no local setup required.
All lessons in this course
- Stable vs Unstable Parameters
- Skipping, @Stable & @Immutable
- Deferring State Reads
- Layout Inspector & Recomposition Counts