Skip to main content

Presence

Enum Presence 

Source
pub enum Presence {
    Visible,
    Hidden,
    Invisible,
    Inactive,
}
Expand description

XFA presence attribute values (XFA 3.3 §2.6 p67-68).

Controls visibility and layout space allocation:

  • Visible – all phases: binding, automation, layout, rendering, interaction.
  • Hidden – binding + automation only; no layout space, no rendering.
  • Invisible – binding + automation + layout; takes up space but not visible.
  • Inactive – binding only; completely absent from form.

Note: spec defines hidden as “effectively absent” (no space) and invisible as “takes space but not visible”. Our is_layout_hidden implementation reflects this.

Variants§

§

Visible

Visible.

§

Hidden

Hidden.

§

Invisible

Invisible.

§

Inactive

Inactive.

Implementations§

Source§

impl Presence

Source

pub fn is_not_visible(self) -> bool

True when the element should not be rendered.

Source

pub fn is_layout_hidden(self) -> bool

True when the element should not occupy layout space.

XFA Spec 3.3 §2.6 (p68):

  • hidden: no layout space, no rendering (effectively absent)
  • invisible: no layout space in Adobe (spec says “takes space”, but empirical testing shows Adobe skips it)
  • inactive: completely absent (no binding, no space)

Hidden was previously excluded from this predicate based on an incorrect assumption that Adobe reserves space for hidden elements. GATE #27 testing proved this wrong: hidden subforms with <break> elements caused 2-23x overpagination in forms with many presence="hidden" subforms (fixes #806).

Trait Implementations§

Source§

impl Clone for Presence

Source§

fn clone(&self) -> Presence

Returns a duplicate of the value. Read more
1.0.0 (const: unstable) · Source§

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

Performs copy-assignment from source. Read more
Source§

impl Debug for Presence

Source§

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

Formats the value using the given formatter. Read more
Source§

impl Default for Presence

Source§

fn default() -> Presence

Returns the “default value” for a type. Read more
Source§

impl PartialEq for Presence

Source§

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

Tests for self and other values to be equal, and is used by ==.
1.0.0 (const: unstable) · Source§

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.
Source§

impl Copy for Presence

Source§

impl Eq for Presence

Source§

impl StructuralPartialEq for Presence

Auto Trait Implementations§

Blanket Implementations§

Source§

impl<T> Any for T
where T: 'static + ?Sized,

Source§

fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more
Source§

impl<T> Borrow<T> for T
where T: ?Sized,

Source§

fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
Source§

impl<T> BorrowMut<T> for T
where T: ?Sized,

Source§

fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more
Source§

impl<T> CloneToUninit for T
where T: Clone,

Source§

unsafe fn clone_to_uninit(&self, dest: *mut u8)

🔬This is a nightly-only experimental API. (clone_to_uninit)
Performs copy-assignment from self to dest. Read more
Source§

impl<T> From<T> for T

Source§

fn from(t: T) -> T

Returns the argument unchanged.

Source§

impl<T, U> Into<U> for T
where U: From<T>,

Source§

fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

Source§

impl<T> ToOwned for T
where T: Clone,

Source§

type Owned = T

The resulting type after obtaining ownership.
Source§

fn to_owned(&self) -> T

Creates owned data from borrowed data, usually by cloning. Read more
Source§

fn clone_into(&self, target: &mut T)

Uses borrowed data to replace owned data, usually by cloning. Read more
Source§

impl<T, U> TryFrom<U> for T
where U: Into<T>,

Source§

type Error = Infallible

The type returned in the event of a conversion error.
Source§

fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

Performs the conversion.
Source§

impl<T, U> TryInto<U> for T
where U: TryFrom<T>,

Source§

type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.
Source§

fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.