[TssHack]

• Closes Axis areas are always keyboard-focusable (Sense::drag), even with allow_axis_zoom_drag(false) #268
• I have followed the instructions in the PR template

Problem

allocate_axis_responses allocated every axis rect with Sense::drag() regardless of
allow_axis_zoom_drag. Sense::drag() is DRAG | FOCUSABLE, and egui gives focus interest
and an AccessKit node to any focusable widget. A static, display-only plot therefore added
two unnamed, inert Tab stops, one per axis. The only way to remove them was
show_axes(false), which also removes the axes.

Reported in #268. I confirmed the mechanism in the pinned egui revision, where
Sense::hover() is Self::empty() and therefore not focusable.

Change

Pick the sense per axis instead of globally:

let axis_sense = |axis| {
    if self.allow_axis_zoom_drag[axis] {
        Sense::drag()
    } else {
        Sense::hover()
    }
};

used as axis_sense(0) / axis_sense(1). Disabling zoom-drag on one axis leaves the other
axis draggable and focusable.

Sense::hover() still participates in hit-testing, so the hover cursor and rect allocation
are unchanged. The drag-to-zoom handler was already guarded by allow_axis_zoom_drag, so
drag behaviour is unchanged. This also documents the new contract on
Plot::allow_axis_zoom_drag.

Scope: one function, no API change, no breaking change.

Tests

Four egui_kittest tests in the existing plot_tests module. The axis areas carry no
accessible name, so they are distinguished by AccessKit bounding-box shape: an x axis is the
wide, short strip along the bottom, a y axis the narrow, tall strip along the left.
Assertions are sorted, so they do not depend on AccessKit traversal order, and no
coordinates are hard-coded.

• disabled_axes_are_not_focusable -- all interactions off: only the following button is focusable.
• enabled_axes_are_focusable -- both axes on: button plus both axis areas are focusable.
• mixed_axes_are_focusable_per_axis -- [true, false] keeps only the x axis; [false, true] keeps only the y axis.
• mixed_axes_are_focusable_at_other_sizes -- the per-axis expectations hold at three other UI sizes.

I checked that the tests actually catch regressions: with both axes wrongly gated on a single
flag (in either direction), mixed_axes_are_focusable_per_axis and
mixed_axes_are_focusable_at_other_sizes fail; with the fix they pass.

The axis shape discrimination was measured rather than assumed: across 153 width/height
combinations the smallest x-axis aspect ratio observed was 2.54 and the largest y-axis aspect
ratio was 0.31, so the "wider than tall" test has a wide margin and does not depend on fonts
or exact pixel sizes.

Validation performed

• cargo test -p egui_plot -- 9 passed, 0 failed; doctests 4 passed, 2 ignored
• cargo clippy -p egui_plot --all-targets --all-features -- -D warnings -- clean
• cargo fmt --all -- --check -- clean
• cargo check --workspace --all-targets -- clean
• git diff --check -- clean

Not run: ./scripts/check.sh (it installs typos-cli and runs cargo deny, which need
network access). Opening as a draft per CONTRIBUTING.md until that has been run.

Disclosure

An AI coding assistant was used to investigate the issue, implement the change, and write the
tests. I reviewed the diff and ran the validation listed above.

Notes for reviewers

• Commit: 24c7dd760b75253953642d0d357e30a6458a5739
• Branch: fix/disabled-axis-keyboard-focus, based on main at a9d6c96
• One file changed: egui_plot/src/plot.rs (+150/-3)

[github-actions]

View snapshot changes at kitdiff

[lucasmerlin]

Thanks! I've changed it so the axis can never have focus, since focus useless there anyways