Struct accesskit::TreeUpdate[−][src]

pub struct TreeUpdate {
    pub nodes: Vec<Node>,
    pub tree: Option<Tree>,
    pub focus: Option<NodeId>,
}

Expand description

A serializable representation of an atomic change to a tree. The sender and receiver must be in sync; the update is only meant to bring the tree from a specific previous state into its next state. Trying to apply it to the wrong tree should immediately panic.

Fields

nodes: Vec<Node>

An ordered list of zero or more node updates to apply to the tree.

Suppose that the next Node to be applied is node. The following invariants must hold:

Either:
1. node.id is already in the tree, or
2. the tree is empty, and node is the new root of the tree.
Every child ID in node.children must either be already a child of this node, or a new ID not previously in the tree. It is not allowed to “reparent” a child to this node without first removing that child from its previous parent.
When a new ID appears in node.children, the tree should create a new uninitialized placeholder node for it immediately. That placeholder must be updated within the same TreeUpdate, otherwise it’s a fatal error. This guarantees the tree is always complete before or after a TreeUpdate.

tree: Option<Tree>

Rarely updated information about the tree as a whole. This may be omitted if it has not changed since the previous update, but providing the same information again is also allowed. This is required when initializing a tree.

focus: Option<NodeId>

The node with keyboard focus within this tree, if any. If the focus is in a descendant tree, set this to the node to which that tree is anchored. The most recent focus, if any, must be provided with every tree update.

This field must contain a value if and only if the native host (e.g. window) currently has the keyboard focus. This implies that the AccessKit provider must track the native focus state and send matching tree updates. Rationale: A robust GUI toolkit must do this native focus tracking anyway in order to correctly render widgets (e.g. to draw or not draw a focus rectangle), so this focus tracking should not be duplicated between the toolkit and the AccessKit platform adapters.

Struct accesskit::TreeUpdate[−][src]

Fields

Trait Implementations

impl Clone for TreeUpdate

fn clone(&self) -> TreeUpdate

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

impl Debug for TreeUpdate

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

impl Default for TreeUpdate

fn default() -> TreeUpdate

impl<'de> Deserialize<'de> for TreeUpdate

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error> where __D: Deserializer<'de>,

impl<T: FnOnce() -> TreeUpdate> From<T> for TreeUpdate

fn from(factory: T) -> Self

impl JsonSchema for TreeUpdate

fn schema_name() -> String

fn json_schema(gen: &mut SchemaGenerator) -> Schema

fn is_referenceable() -> bool

impl PartialEq<TreeUpdate> for TreeUpdate

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

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

impl Serialize for TreeUpdate

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error> where __S: Serializer,

impl StructuralPartialEq for TreeUpdate

Auto Trait Implementations

impl RefUnwindSafe for TreeUpdate

impl Send for TreeUpdate

impl Sync for TreeUpdate

impl Unpin for TreeUpdate

impl UnwindSafe for TreeUpdate

Blanket Implementations

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

pub fn type_id(&self) -> TypeId

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

pub fn borrow(&self) -> &T

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

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

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

pub fn __clone_box(&self, Private) -> *mut ()

impl<T> From<T> for T

pub fn from(t: T) -> T

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

pub fn into(self) -> U

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

type Owned = T

pub fn to_owned(&self) -> T

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

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

type Error = Infallible

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

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

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

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

impl<T> DeserializeOwned for T where T: for<'de> Deserialize<'de>,

fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> where
__D: Deserializer<'de>,

fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> where
S: Serializer,

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

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

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

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

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

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

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

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

impl<T> DeserializeOwned for T where
T: for<'de> Deserialize<'de>,