Add: hold a binding as @Binding, not a plain stored property - #76
Merged
Merged
Conversation
A binding stored in an undecorated property (let/var x: Binding<T>) is invisible to SwiftUI's dependency tracking, because only DynamicProperty properties are unwrapped and subscribed to. The view then fails to re-evaluate when the bound value changes from elsewhere. Debug builds can mask this with extra graph passes, so it often surfaces only in Release. Adds a subsection under @binding and a matching Key Principles entry.
larryonoff
force-pushed
the
add-binding-not-plain-property
branch
from
July 3, 2026 10:47
ee2c567 to
1b4d3b9
Compare
AvdLee
approved these changes
Jul 24, 2026
AvdLee
left a comment
AvdLee
left a comment
Owner
There was a problem hiding this comment.
LGTM, thanks for your contribution!
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Adds a
### Declare a Binding with @Binding, Not a Plain Propertysubsection under## @Binding(plus a matching Key Principles entry).Why: a binding held in an undecorated property (
let x: Binding<T>) is invisible to SwiftUI tracking — onlyDynamicPropertyproperties are subscribed to — so external changes don't re-evaluate the view. Distinct from the existing "don't use@Bindingfor read-only" note: here the developer wants reactivity but declares it wrong. Often a Release-only failure; hitsUIViewRepresentablehardest.Docs-only, ToC unchanged (new heading is
###, like the sibling@Bindingsubsections).Test notes: verified a view storing
let selection: Binding<Item?>didn't re-evaluate on external reset in Release;@Binding var selection: Item?fixed it.