Trait Layout 

pub trait Layout {
    // Required methods
    fn device(&self) -> &Device;
    fn set_theme(&mut self, theme: Theme) -> bool;
    fn set_viewport_details(
        &mut self,
        viewport_details: ViewportDetails,
    ) -> bool;
    fn load_web_fonts_from_stylesheet(
        &self,
        stylesheet: &ServoArc<Stylesheet>,
        font_context: &WebFontDocumentContext,
    );
    fn add_stylesheet(
        &mut self,
        stylesheet: ServoArc<Stylesheet>,
        before_stylsheet: Option<ServoArc<Stylesheet>>,
        font_context: &WebFontDocumentContext,
    );
    fn exit_now(&mut self);
    fn collect_reports(
        &self,
        reports: &mut Vec<Report>,
        ops: &mut MallocSizeOfOps,
    );
    fn set_quirks_mode(&mut self, quirks_mode: QuirksMode);
    fn remove_stylesheet(&mut self, stylesheet: ServoArc<Stylesheet>);
    fn remove_cached_image(&mut self, image_url: &ServoUrl);
    fn reflow(&mut self, reflow_request: ReflowRequest) -> Option<ReflowResult>;
    fn ensure_stacking_context_tree(&self, viewport_details: ViewportDetails);
    fn register_paint_worklet_modules(
        &mut self,
        name: Atom,
        properties: Vec<Atom>,
        painter: Box<dyn Painter>,
    );
    fn set_scroll_offsets_from_renderer(
        &mut self,
        scroll_states: &FxHashMap<ExternalScrollId, LayoutVector2D>,
    );
    fn scroll_offset(&self, id: ExternalScrollId) -> Option<LayoutVector2D>;
    fn needs_new_display_list(&self) -> bool;
    fn set_needs_new_display_list(&self);
    fn node_rendering_type(
        &self,
        node: TrustedNodeAddress,
        pseudo: Option<PseudoElement>,
    ) -> NodeRenderingType;
    fn query_containing_block(
        &self,
        node: TrustedNodeAddress,
    ) -> Option<UntrustedNodeAddress>;
    fn query_padding(&self, node: TrustedNodeAddress) -> Option<PhysicalSides>;
    fn query_box_area(
        &self,
        node: TrustedNodeAddress,
        area: BoxAreaType,
        exclude_transform_and_inline: bool,
    ) -> Option<Rect<Au, CSSPixel>>;
    fn query_box_areas(
        &self,
        node: TrustedNodeAddress,
        area: BoxAreaType,
    ) -> CSSPixelRectIterator;
    fn query_client_rect(&self, node: TrustedNodeAddress) -> Rect<i32, CSSPixel>;
    fn query_current_css_zoom(&self, node: TrustedNodeAddress) -> f32;
    fn query_element_inner_outer_text(&self, node: TrustedNodeAddress) -> String;
    fn query_offset_parent(
        &self,
        node: TrustedNodeAddress,
    ) -> OffsetParentResponse;
    fn query_scroll_container(
        &self,
        node: Option<TrustedNodeAddress>,
        flags: ScrollContainerQueryFlags,
    ) -> Option<ScrollContainerResponse>;
    fn query_resolved_style(
        &self,
        node: TrustedNodeAddress,
        pseudo: Option<PseudoElement>,
        property_id: PropertyId,
        animations: DocumentAnimationSet,
        animation_timeline_value: f64,
    ) -> String;
    fn query_resolved_font_style(
        &self,
        node: TrustedNodeAddress,
        value: &str,
        animations: DocumentAnimationSet,
        animation_timeline_value: f64,
    ) -> Option<ServoArc<Font>>;
    fn query_scrolling_area(
        &self,
        node: Option<TrustedNodeAddress>,
    ) -> Rect<i32, CSSPixel>;
    fn query_text_index(
        &self,
        node: TrustedNodeAddress,
        point: Point2D<Au, CSSPixel>,
    ) -> Option<usize>;
    fn query_elements_from_point(
        &self,
        point: LayoutPoint,
        flags: ElementsFromPointFlags,
    ) -> Vec<ElementsFromPointResult>;
    fn query_effective_overflow(
        &self,
        node: TrustedNodeAddress,
    ) -> Option<AxesOverflow>;
    fn stylist_mut(&mut self) -> &mut Stylist;
    fn set_accessibility_active(&self, enabled: bool, epoch: Epoch);
    fn needs_accessibility_update(&self) -> bool;
    fn set_needs_accessibility_update(&self);
}

Required Methods

fn device(&self) -> &Device

Get a reference to this Layout’s Stylo Device used to handle media queries and resolve font metrics.

fn set_theme(&mut self, theme: Theme) -> bool

Set the theme on this Layout’s Device. The caller should also trigger a new layout when this happens, though it can happen later. Returns true if the Theme actually changed or false otherwise.

fn set_viewport_details(&mut self, viewport_details: ViewportDetails) -> bool

Set the ViewportDetails on this Layout’s Device. The caller should also trigger a new layout when this happens, though it can happen later. Returns true if the ViewportDetails actually changed or false otherwise.

fn load_web_fonts_from_stylesheet( &self, stylesheet: &ServoArc<Stylesheet>, font_context: &WebFontDocumentContext, )

Load all fonts from the given stylesheet, returning the number of fonts that need to be loaded.

fn add_stylesheet( &mut self, stylesheet: ServoArc<Stylesheet>, before_stylsheet: Option<ServoArc<Stylesheet>>, font_context: &WebFontDocumentContext, )

Add a stylesheet to this Layout. This will add it to the Layout’s Stylist as well as loading all web fonts defined in the stylesheet. The second stylesheet is the insertion point (if it exists, the sheet needs to be inserted before it).

fn exit_now(&mut self)

Inform the layout that its ScriptThread is about to exit.

fn collect_reports(&self, reports: &mut Vec<Report>, ops: &mut MallocSizeOfOps)

Requests that layout measure its memory usage. The resulting reports are sent back via the supplied channel.

fn set_quirks_mode(&mut self, quirks_mode: QuirksMode)

Sets quirks mode for the document, causing the quirks mode stylesheet to be used.

fn remove_stylesheet(&mut self, stylesheet: ServoArc<Stylesheet>)

Removes a stylesheet from the Layout.

fn remove_cached_image(&mut self, image_url: &ServoUrl)

Removes an image from the Layout image resolver cache.

fn reflow(&mut self, reflow_request: ReflowRequest) -> Option<ReflowResult>

Requests a reflow.

fn ensure_stacking_context_tree(&self, viewport_details: ViewportDetails)

Do not request a reflow, but ensure that any previous reflow completes building a stacking context tree so that it is ready to query the final size of any elements in script.

fn register_paint_worklet_modules( &mut self, name: Atom, properties: Vec<Atom>, painter: Box<dyn Painter>, )

Tells layout that script has added some paint worklet modules.

fn set_scroll_offsets_from_renderer( &mut self, scroll_states: &FxHashMap<ExternalScrollId, LayoutVector2D>, )

Set the scroll states of this layout after a Paint scroll.

fn scroll_offset(&self, id: ExternalScrollId) -> Option<LayoutVector2D>

Get the scroll offset of the given scroll node with id of ExternalScrollId or None if it does not exist in the tree.

fn needs_new_display_list(&self) -> bool

Returns true if this layout needs to produce a new display list for rendering updates.

fn set_needs_new_display_list(&self)

Marks that this layout needs to produce a new display list for rendering updates.

fn node_rendering_type( &self, node: TrustedNodeAddress, pseudo: Option<PseudoElement>, ) -> NodeRenderingType

Returns the NodeRenderingType for this node and pseudo. This is used to determine if a node is being rendered, delegating its rendering, or not being rendered at all.

fn query_containing_block( &self, node: TrustedNodeAddress, ) -> Option<UntrustedNodeAddress>

fn query_padding(&self, node: TrustedNodeAddress) -> Option<PhysicalSides>

fn query_box_area( &self, node: TrustedNodeAddress, area: BoxAreaType, exclude_transform_and_inline: bool, ) -> Option<Rect<Au, CSSPixel>>

fn query_box_areas( &self, node: TrustedNodeAddress, area: BoxAreaType, ) -> CSSPixelRectIterator

fn query_client_rect(&self, node: TrustedNodeAddress) -> Rect<i32, CSSPixel>

fn query_current_css_zoom(&self, node: TrustedNodeAddress) -> f32

fn query_element_inner_outer_text(&self, node: TrustedNodeAddress) -> String

fn query_offset_parent(&self, node: TrustedNodeAddress) -> OffsetParentResponse

fn query_scroll_container( &self, node: Option<TrustedNodeAddress>, flags: ScrollContainerQueryFlags, ) -> Option<ScrollContainerResponse>

Query the scroll container for the given node. If node is None, the scroll container for the viewport is returned.

fn query_resolved_style( &self, node: TrustedNodeAddress, pseudo: Option<PseudoElement>, property_id: PropertyId, animations: DocumentAnimationSet, animation_timeline_value: f64, ) -> String

fn query_resolved_font_style( &self, node: TrustedNodeAddress, value: &str, animations: DocumentAnimationSet, animation_timeline_value: f64, ) -> Option<ServoArc<Font>>

fn query_scrolling_area( &self, node: Option<TrustedNodeAddress>, ) -> Rect<i32, CSSPixel>

fn query_text_index( &self, node: TrustedNodeAddress, point: Point2D<Au, CSSPixel>, ) -> Option<usize>

Find the character offset of the point in the given node, if it has text content.

fn query_elements_from_point( &self, point: LayoutPoint, flags: ElementsFromPointFlags, ) -> Vec<ElementsFromPointResult>

fn query_effective_overflow( &self, node: TrustedNodeAddress, ) -> Option<AxesOverflow>

fn stylist_mut(&mut self) -> &mut Stylist

fn set_accessibility_active(&self, enabled: bool, epoch: Epoch)

Set whether the accessibility tree should be constructed for this Layout. This should be called by the embedder when accessibility is requested by the user.

fn needs_accessibility_update(&self) -> bool

Whether the accessibility tree needs updating. This is set to true when

• accessibility is activated; or
• a page is loaded after accesibility is activated.

In future, this should be set to true if DOM or style have changed in a way that impacts the accessibility tree.

Checked in can_skip_reflow_request_entirely(), as a dirty accessibility tree should force a reflow, and handle_reflow() to determine whether to update the accessibility tree during reflow.

fn set_needs_accessibility_update(&self)

See Self::needs_accessibility_update().

Implementors