Struct SlotInstance

pub struct SlotInstance { /* private fields */ }

A special “control-flow” primitive (a la yield or perhaps goto) — represents a slot into which an slot_child can be rendered. Slot relies on slot_children being present on the [Runtime] stack and will not render any content if there are no slot_children found.

Consider a Stacker: the owner of a Stacker passes the Stacker some nodes to render inside the cells of the Stacker. To the owner of the Stacker, those nodes might seem like “children,” but to the Stacker they are “slot_children” — children provided from the outside. Inside Stacker’s template, there are a number of Slots — this primitive — that become the final rendered home of those slot_children. This same technique is portable and applicable elsewhere via Slot.

Trait Implementations

impl InstanceNode for SlotInstance

fn instantiate(args: InstantiationArgs) -> Rc<Self>

where Self: Sized,

fn handle_mount( self: Rc<Self>, expanded_node: &Rc<ExpandedNode>, context: &Rc<RuntimeContext>, )

Fires during the tick when a node is first attached to the render tree. For example, this event fires by all nodes on the global first tick, and by all nodes in a subtree when a Conditional subsequently turns on a subtree (i.e. when the Conditionals criterion becomes true after being false through the end of at least 1 frame.) A use-case: send a message to native renderers that a Text element should be rendered and tracked

fn resolve_debug( &self, f: &mut Formatter<'_>, _expanded_node: Option<&ExpandedNode>, ) -> Result

fn base(&self) -> &BaseInstance

Retrieves the base instance, containing common functionality that all instances share

fn update( self: Rc<Self>, _expanded_node: &Rc<ExpandedNode>, _context: &Rc<RuntimeContext>, )

Updates the expanded node, recomputing its properties and possibly updating its children

fn handle_pre_render( &self, expanded_node: &ExpandedNode, context: &Rc<RuntimeContext>, rcs: &mut dyn RenderContext, )

Second lifecycle method during each render loop, occurs after properties have been computed, but before rendering Example use-case: perform side-effects to the drawing contexts. This is how [Frame] performs clipping, for example. Occurs in a pre-order traversal of the render tree.

fn render( &self, expanded_node: &ExpandedNode, context: &Rc<RuntimeContext>, rcs: &mut dyn RenderContext, )

Third lifecycle method during each render loop, occurs after all descendents have been rendered. Occurs in a post-order traversal of the render tree. Most primitives are expected to draw their contents to the rendering context during this event.

fn handle_post_render( &self, expanded_node: &ExpandedNode, context: &Rc<RuntimeContext>, rcs: &mut dyn RenderContext, )

Fourth and final lifecycle method during each render loop, occurs after all descendents have been rendered AND the current node has been rendered. Useful for clean-up, e.g. this is where Frame cleans up the drawing contexts to stop clipping. Occurs in a post-order traversal of the render tree.

fn handle_unmount( &self, expanded_node: &Rc<ExpandedNode>, context: &Rc<RuntimeContext>, )

Fires during element unmount, when an element is about to be removed from the render tree (e.g. by a Conditional) A use-case: send a message to native renderers that a Text element should be removed

fn handle_scroll(&self, args_scroll: Scroll)

Invoked by event interrupts to pass scroll information to render node

fn get_template(&self) -> Option<&InstanceNodePtrList>

fn clips_content(&self, _expanded_node: &ExpandedNode) -> bool

Used by frame to control content clipping

fn handle_native_interrupt( &self, _expanded_node: &Rc<ExpandedNode>, _interrupt: &NativeInterrupt, )

fn handle_control_flow_node_expansion( self: Rc<Self>, _expanded_node: &Rc<ExpandedNode>, _context: &Rc<RuntimeContext>, )

fn handle_setup_slot_children( self: Rc<Self>, _expanded_node: &Rc<ExpandedNode>, _context: &Rc<RuntimeContext>, )