Struct Canvas 

pub struct Canvas<P>
where
    P: CanvasProgram,
{ /* private fields */ }

Available on crate features resvg or tiny-skia only.

A canvas widget over the tiny-skia library

The widget is essentially a cached image drawn from a Pixmap controlled through an implementation of CanvasProgram. Note that the tiny-skia API is re-exported as crate::tiny_skia.

By default, a Canvas has a minimum size of 128x128 pixels and a high stretch factor (i.e. will greedily occupy extra space). To adjust this call one of the sizing/scaling methods.

Implementations

impl<P> Canvas<P>

where P: CanvasProgram,

pub fn new(program: P) -> Canvas<P>

Construct

Use Self::with_size or Self::with_scaling to set the initial size.

pub fn with_size(self, size: LogicalSize) -> Canvas<P>

Assign size

Default size is 128 × 128.

pub fn with_scaling(self, f: impl FnOnce(&mut PixmapScaling)) -> Canvas<P>

Adjust scaling

Default size is 128 × 128; default stretch is Stretch::High. Other fields use PixmapScaling’s default values.

pub fn set_scaling( &mut self, cx: &mut EventState, f: impl FnOnce(&mut PixmapScaling), )

Adjust scaling

Default size is 128 × 128; default stretch is Stretch::High. Other fields use PixmapScaling’s default values.

Trait Implementations

impl<P> Clone for Canvas<P>

where P: Clone + CanvasProgram,

fn clone(&self) -> Canvas<P>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<P> Debug for Canvas<P>

where P: CanvasProgram,

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

Formats the value using the given formatter.

impl<P> Events for Canvas<P>

where P: CanvasProgram,

fn handle_messages( &mut self, cx: &mut EventCx<'_>, _: &<Canvas<P> as Widget>::Data, )

Handler for messages from children/descendants

fn handle_event( &mut self, _: &mut EventCx<'_>, _: &<Canvas<P> as Widget>::Data, _: Event<'_>, ) -> IsUsed

Handle an Event

const REDRAW_ON_MOUSE_OVER: bool = false

Does this widget have a different appearance on mouse over?

fn mouse_over_icon(&self) -> Option<CursorIcon>

The mouse cursor icon to use on mouse over

fn make_child_id(&mut self, index: usize) -> Id

Make an identifier for a child

fn configure(&mut self, cx: &mut ConfigCx<'_>)

Configure self

fn configure_recurse(&mut self, cx: &mut ConfigCx<'_>, data: &Self::Data)

Configure children

fn update(&mut self, cx: &mut ConfigCx<'_>, data: &Self::Data)

Update self using input data

fn update_recurse(&mut self, cx: &mut ConfigCx<'_>, data: &Self::Data)

Update children

fn handle_mouse_over(&mut self, cx: &mut EventCx<'_>, state: bool)

Mouse focus handler

fn handle_scroll( &mut self, cx: &mut EventCx<'_>, data: &Self::Data, scroll: Scroll, )

Handler for scrolling

impl<P> Layout for Canvas<P>

where P: CanvasProgram,

fn rect(&self) -> Rect

Get the widget’s region

fn size_rules(&mut self, sizer: SizeCx<'_>, axis: AxisInfo) -> SizeRules

Get size rules for the given axis

fn set_rect(&mut self, cx: &mut ConfigCx<'_>, rect: Rect, hints: AlignHints)

Set size and position

fn draw(&self, draw: DrawCx<'_>)

Draw a widget and its children

fn try_probe(&self, coord: Coord) -> Option<Id>

Probe a coordinate for a widget’s Id

impl<P> Tile for Canvas<P>

where P: CanvasProgram,

fn role(&self, _: &mut dyn RoleCx) -> Role<'_>

Describe the widget’s role

fn as_tile(&self) -> &dyn Tile

Get as a dyn Tile

fn id_ref(&self) -> &Id

Get a reference to the widget’s identifier

fn identify(&self) -> IdentifyWidget<'_>

Return a Display-able widget identifier

fn get_child(&self, index: usize) -> Option<&dyn Tile>

Access a child as a dyn Tile, if available

fn child_indices(&self) -> ChildIndices

Get child indices available to recursion

fn nav_next(&self, reverse: bool, from: Option<usize>) -> Option<usize>

Navigation in spatial order

fn probe(&self, coord: Coord) -> Id

Probe a coordinate for a widget’s Id

fn id(&self) -> Id

Get the widget’s identifier

fn navigable(&self) -> bool

Whether this widget supports navigation focus

fn tooltip(&self) -> Option<&str>

Tooltip

fn role_child_properties(&self, cx: &mut dyn RoleCx, index: usize)

Specify additional role properties for child index

fn find_child_index(&self, id: &Id) -> Option<usize>

Find the child which is an ancestor of this id, if any

fn translation(&self, index: usize) -> Offset

Get translation of child index relative to this widget

impl<P> Widget for Canvas<P>

where P: CanvasProgram,

type Data = ()

Input data type

fn as_node<'__a>( &'__a mut self, data: &'__a <Canvas<P> as Widget>::Data, ) -> Node<'__a>

Erase type

fn child_node<'__n>( &'__n mut self, data: &'__n <Canvas<P> as Widget>::Data, index: usize, ) -> Option<Node<'__n>>

Access a child as a Node, if available