Struct PopupView 

pub struct PopupView {
    pub annot: AnnotId,
    pub anchor: Rect,
    pub geometry: PopupGeometry,
    pub options: Vec<String>,
    pub selected: Option<usize>,
    pub hovered: Option<usize>,
    pub top_visible: usize,
    pub edit_text: Option<String>,
}

Everything a host needs to draw one open dropdown.

Returned by crate::route::popup_view.

Owned, not borrowed from the session. A per-page entry point assembles a borrowed crate::route::Context, drives the body and drops it, so a view that borrowed the session could not outlive the call. The cost is a Vec<String> per query, on a query a host makes once per render of a page that has a dropdown open.

Fields

annot: AnnotId

Which widget the list belongs to, by raw /Annots index — the same key space appearance updates and the annotation overlay use.

anchor: Rect

The widget’s own /Rect, page space: the anchor the list hangs from.

geometry: PopupGeometry

Where the list is and how tall its rows are.

options: Vec<String>

The rows’ labels, in option order.

Labels and not values: a list shows crate::field::ChoiceOption::label, while value is what the field stores when they differ, and drawing the latter would put the wrong string on the page for every /Opt entry written as a two-element array.

selected: Option<usize>

Which option is selected, if any.

A combo box selects at most one — field::choice::select_only is the only path a click into the list takes — so this is an index and not a set.

hovered: Option<usize>

Which option the pointer is over, if any.

Hovering a row selects it rather than merely tinting it. This reports the pointer’s row so a host can paint the band before the click lands.

top_visible: usize

The first option currently showing, for a list taller than the popup.

edit_text: Option<String>

An editable combo’s text half, which is a typed string rather than an option’s label. None for a gated combo, which has no text half.

Implementations

impl PopupView

pub fn label_at(&self, offset: usize) -> Option<&str>

The label of one visible row, counting offset rows down from the first one showing.

The pairing for PopupGeometry::row_rect: the two take the same offset, so a painter walks 0..visible_rows() asking each for its rectangle and its text without doing the top_visible arithmetic itself.

pub fn is_banded(&self, offset: usize) -> bool

Whether the row at offset visible rows down is the selected one.

The band drawn navy with white text. Hover counts: the row under the pointer is selected as far as the drawing is concerned, even though the field’s stored value has not moved.

Trait Implementations

impl Clone for PopupView

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for PopupView

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl PartialEq for PopupView

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for PopupView