Struct kas_resvg::Canvas

pub struct Canvas<P: CanvasDrawable> {
    pub program: P,
    // some fields omitted
}

This is supported on crate feature canvas only.

A canvas widget over the tiny-skia library

Note that the tiny-skia API is re-exported as crate::tiny_skia.

Canvas size is controlled by the sizing arguments passed to the constructor, as well as the stretch factor and the display’s scale factor sf. Minimum size is min_size * sf. Ideal size is ideal_size * sf except that if fix_aspect is true, then the ideal height is the one that preserves aspect ratio for the given width. The canvas may also exceed the ideal size if a Stretch factor greater than None is used.

The canvas (re)creates the backing pixmap when the size is set and draws to the new pixmap immediately. If the canvas program is modified then Canvas::redraw must be called to update the pixmap.

Fields

program: P

The program drawing to the canvas

Implementations

impl<P: CanvasDrawable> Canvas<P>

pub fn new(program: P, size: Size) -> Self

Construct with given size

Creates a new canvas with a given size. The size is adjusted according to the display’s scale factor.

pub fn with_scaling(
    self,
    f: impl FnOnce(SpriteDisplay) -> SpriteDisplay
) -> Self

Adjust scaling

pub fn set_scaling(&mut self, f: impl FnOnce(&mut SpriteDisplay)) -> TkAction

Adjust scaling

pub fn redraw(&mut self, mgr: &mut Manager<'_>)

Redraw immediately

Other than this, the canvas is only drawn when the backing pixmap is (re)created: on start and on resizing.

This method does nothing before a backing pixmap has been created.

Trait Implementations

impl<P: Clone + CanvasDrawable> Clone for Canvas<P>

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

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<P: Debug + CanvasDrawable> Debug for Canvas<P>

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

Formats the value using the given formatter.

impl<P: CanvasDrawable> Handler for Canvas<P>

type Msg = VoidMsg

Type of message returned by this widget

fn activation_via_press(&self) -> bool

Generic handler: translate presses to activations

fn focus_on_key_nav(&self) -> bool

Generic handler: focus rect on key navigation

fn handle(&mut self, mgr: &mut Manager<'_>, event: Event) -> Response<Self::Msg>

Handle an event and return a user-defined message

impl<P: CanvasDrawable> Layout for Canvas<P>

fn size_rules(&mut self, sh: &mut dyn SizeHandle, axis: AxisInfo) -> SizeRules

Get size rules for the given axis

fn set_rect(&mut self, mgr: &mut Manager<'_>, rect: Rect, align: AlignHints)

Apply a given rect to self

fn draw(&self, draw: &mut dyn DrawHandle, _: &ManagerState, _: bool)

Draw a widget and its children

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

Get translation of a child

fn spatial_nav(
    &mut self,
    mgr: &mut Manager<'_>,
    reverse: bool,
    from: Option<usize>
) -> Option<usize>

Navigation in spatial order

fn find_id(&self, coord: Coord) -> Option<WidgetId>

Find a widget by coordinate

impl<P: CanvasDrawable> SendEvent for Canvas<P>

fn send(
    &mut self,
    mgr: &mut Manager<'_>,
    id: WidgetId,
    event: Event
) -> Response<Self::Msg>

Send an event

impl<P: CanvasDrawable> WidgetChildren for Canvas<P>

fn first_id(&self) -> WidgetId

Get the first identifier of self or any children

fn num_children(&self) -> usize

Get the number of child widgets

fn get_child(&self, _index: usize) -> Option<&dyn WidgetConfig>

Get a reference to a child widget by index, or None if the index is out of bounds.

fn get_child_mut(&mut self, _index: usize) -> Option<&mut dyn WidgetConfig>

Mutable variant of get

fn record_first_id(&mut self, _id: WidgetId)

Record first identifier

fn is_ancestor_of(&self, id: WidgetId) -> bool

Check whether id is a descendant

fn find_child(&self, id: WidgetId) -> Option<usize>

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

fn find_leaf(&self, id: WidgetId) -> Option<&(dyn WidgetConfig + 'static)>

Find the leaf (lowest descendant) with this id, if any

fn find_leaf_mut(
    &mut self,
    id: WidgetId
) -> Option<&mut (dyn WidgetConfig + 'static)>

Find the leaf (lowest descendant) with this id, if any

fn walk_children<F>(&self, f: F) where
    F: FnMut(&(dyn WidgetConfig + 'static)), 

Walk through all widgets, calling f once on each.

fn walk_children_mut<F>(&mut self, f: F) where
    F: FnMut(&mut (dyn WidgetConfig + 'static)), 

Walk through all widgets, calling f once on each.

impl<P: CanvasDrawable> WidgetConfig for Canvas<P>

fn key_nav(&self) -> bool

Is this widget navigable via Tab key?

fn hover_highlight(&self) -> bool

Does this widget have hover-state highlighting?

fn cursor_icon(&self) -> CursorIcon

Which cursor icon should be used on hover?

fn configure(&mut self, &mut Manager<'_>)

Configure widget

fn configure_recurse(&mut self, cmgr: ConfigureManager<'_, '_>)

Configure self and children

impl<P: CanvasDrawable> WidgetCore for Canvas<P>

fn as_any(&self) -> &dyn Any

Get self as type Any

fn as_any_mut(&mut self) -> &mut dyn Any

Get self as type Any (mutable)

fn core_data(&self) -> &CoreData

Get direct access to the CoreData providing property storage.

fn core_data_mut(&mut self) -> &mut CoreData

fn widget_name(&self) -> &'static str

Get the name of the widget struct

fn as_widget(&self) -> &dyn WidgetConfig

Erase type

fn as_widget_mut(&mut self) -> &mut dyn WidgetConfig

Erase type

fn id(&self) -> WidgetId

Get the widget’s numeric identifier

fn is_disabled(&self) -> bool

Get whether the widget is disabled

fn set_disabled(&mut self, disabled: bool) -> TkAction

Set the disabled state of a widget

fn with_disabled(self, disabled: bool) -> Self

Set disabled state (chaining)

fn rect(&self) -> Rect

Get the widget’s region, relative to its parent.

fn input_state(&self, mgr: &ManagerState, disabled: bool) -> InputState

Construct InputState

impl<P: CanvasDrawable> Widget for Canvas<P>