Fix TextBox caret overlapping last glyph at end of line#21059
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jdmichel wants to merge 1 commit intoAvaloniaUI:masterfrom
Open
Fix TextBox caret overlapping last glyph at end of line#21059jdmichel wants to merge 1 commit intoAvaloniaUI:masterfrom
jdmichel wants to merge 1 commit intoAvaloniaUI:masterfrom
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GetCaretPoints() subtracted 1px from the caret X position when the caret was at or past the line width, to prevent clipping at the control boundary. This caused the caret to render on top of the last character instead of after it — visible at all font sizes and font families. Fix: replace "x -= 1" with "x = Math.Ceiling(X) + 0.5" so the caret snaps to the next pixel boundary past the glyph. Reserve 2px of extra width in MeasureOverride so the caret is not clipped. Fixes AvaloniaUI#12809
MrJul
added
bug
backport-candidate-11.3.x
Contributor
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A real fix to this issue is drawing the caret via an adorner layer |
Collaborator
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You can test this PR using the following package version. |
Author
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@cla-avalonia agree |
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Summary
GetCaretPoints()subtracts 1px from the caret X position when the caretis at or past the line width, to prevent clipping at the control boundary.
This causes the caret to render on top of the last character instead
of after it — visible at all font sizes and font families.
Changes
GetCaretPoints(): Replacex -= 1withx = Math.Ceiling(X) + 0.5so the caret snaps to the next pixelboundary past the glyph, guaranteeing visible separation.
MeasureOverride(): Reserve 2 extra pixels of width(
textWidth + 2) so the caret is not clipped by the control boundary.Diagnostic evidence
Minimal repro app traces
_lastCharacterHitand_caretBoundsviareflection. For text "rrrrrrr" at FontSize 23:
The CharacterHit logic resolves correctly. The only corruption is
x -= 1inGetCaretPoints():Repro
Any Avalonia app with a TextBox — type text and observe the caret at
the end of the string overlaps the last character. Tested on Windows
with Avalonia 11.3.12, 11.3.13, .NET 9, .NET 10, multiple fonts and
font sizes.
Fixes #12809