fix: disable usesFontLeading on UITextView's layoutManager#45
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UITextView's NSLayoutManager defaults to usesFontLeading = YES, while RCTTextLayoutManager (used in measureContent) measures with NO. Custom fonts with non-zero leading then render taller per line than RN measured, accumulating into bottom-of-view cutoff for paragraphs. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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Summary
Fixes #42.
RCTTextLayoutManager— which the shadow node calls inmeasureContentto size the view — measures withusesFontLeading = NO.UITextView'sNSLayoutManagerdefaults tousesFontLeading = YES. When a custom font with non-zero natural leading is used, UITextView renders each line slightly taller than RN measured. The shortfall accumulates over many lines and the last line(s) of the paragraph fall outside the view's clip bounds.The fix is one line: explicitly set
usesFontLeading = NOon the textView's layout manager so rendering matches measurement.System fonts have ~zero leading, which is why the bug doesn't show up without a custom
fontFamily.Test plan
<UITextView selectable uiTextView style={{fontFamily: 'Inter'}}>is no longer cut off at the bottom.onTextLayoutstill work.numberOfLinestruncation cases in the example app are unchanged.🤖 Generated with Claude Code