Expand description
Per-column filter popover UI.
HeaderCell renders a small filter glyph (the unconditional
FilterIndicator paint widget) after the sort indicator when the
column is filterable. Tapping the glyph opens a Popover
anchored to it whose content is a FilterPopoverContent widget — a
TextInput with a trailing IconButton::clear bound to the
table’s filters_signal[col_id] slot. Callers can also drive
filters_signal programmatically.