focusPreviousPage method
void
focusPreviousPage()
Focus previous page. Port of focus-previous-page action from use-select-navigation.ts reducer.
Implementation
void focusPreviousPage() {
final current = focusedValue.value;
if (current == null) return;
final item = optionMap.get(current);
if (item == null) return;
final targetIndex = math.max(0, item.index - visibleOptionCount);
OptionMapItem<T>? target = optionMap.first;
for (int i = 0; i < targetIndex && target != null; i++) {
target = target.next;
}
if (target == null) return;
focusedValue.value = target.value;
_scrollToFocus();
onFocus?.call(target.value);
}