@ue-too/board / index / CanvasProxy

類別: CanvasProxy

定義於: packages/board/src/input-interpretation/input-state-machine/kmt-input-context.ts:179

A proxy for the canvas element to prevent constant invoking of the getBoundingClientRect method.

備註

This is mainly used as a proxy to the canvas to prevent invoking the getBoundingClientRect method on the canvas every time a pointer event is triggered or a coordinate conversion is needed. Also to autoscale the canvas buffer depending on the device pixel ratio. It's important to note that in normal circumstances, you would not need to set the size of the canvas manually; you should use the css style width and height to set the size of the canvas.

參閱

• Canvas for the interface that this class implements
• Observable for the observable that this class emits
• Observer for the observer that can subscribe to the observable
• SubscriptionOptions for the options that can be passed to the subscribe method
• SynchronousObservable for the synchronous observable that this class emits
• CanvasPositionDimensionPublisher for the publisher that is used to publish the canvas dimensions

實作

• Canvas
• Observable<[CanvasDimensions]>

建構函式

建構函式

new CanvasProxy(canvas?): CanvasProxy

定義於: packages/board/src/input-interpretation/input-state-machine/kmt-input-context.ts:187

參數

canvas?

HTMLCanvasElement

回傳

CanvasProxy

存取器

detached

Getter 簽章

get detached(): boolean

定義於: packages/board/src/input-interpretation/input-state-machine/kmt-input-context.ts:238

Whether the canvas is currently detached from the DOM

回傳

boolean

Whether the canvas is currently detached from the DOM

實作了

Canvas.detached

---

dimensions

Getter 簽章

get dimensions(): object

定義於: packages/board/src/input-interpretation/input-state-machine/kmt-input-context.ts:242

Combined dimensions and position information

回傳

object

height

height: number

position

position: Point

width

width: number

Combined dimensions and position information

實作了

Canvas.dimensions

---

height

Getter 簽章

get height(): number

定義於: packages/board/src/input-interpretation/input-state-machine/kmt-input-context.ts:308

The canvas height in CSS pixels

回傳

number

The canvas height in CSS pixels

實作了

Canvas.height

---

position

Getter 簽章

get position(): Point

定義於: packages/board/src/input-interpretation/input-state-machine/kmt-input-context.ts:312

The top-left position of the canvas in window coordinates

回傳

Point

The top-left position of the canvas in window coordinates

實作了

Canvas.position

---

width

Getter 簽章

get width(): number

定義於: packages/board/src/input-interpretation/input-state-machine/kmt-input-context.ts:250

The canvas width in CSS pixels

回傳

number

The canvas width in CSS pixels

實作了

Canvas.width

方法

attach()

attach(canvas): void

定義於: packages/board/src/input-interpretation/input-state-machine/kmt-input-context.ts:330

參數

canvas

HTMLCanvasElement

回傳

void

---

notify()

notify(...data): void

定義於: packages/board/src/input-interpretation/input-state-machine/kmt-input-context.ts:234

參數

data

...[CanvasDimensions]

回傳

void

實作了

Observable.notify

---

setCanvasHeight()

setCanvasHeight(height): void

定義於: packages/board/src/input-interpretation/input-state-machine/kmt-input-context.ts:292

參數

height

number

回傳

void

---

setCanvasWidth()

setCanvasWidth(width): void

定義於: packages/board/src/input-interpretation/input-state-machine/kmt-input-context.ts:265

參數

width

number

回傳

void

---

setCursor()

setCursor(style): void

定義於: packages/board/src/input-interpretation/input-state-machine/kmt-input-context.ts:316

Sets the CSS cursor style for visual feedback

參數

style

"grab" | "default" | "grabbing"

回傳

void

實作了

Canvas.setCursor

---

setHeight()

setHeight(height): void

定義於: packages/board/src/input-interpretation/input-state-machine/kmt-input-context.ts:285

set the height of the canvas the height is synonymous with the canvas style height not the canvas height

參數

height

number

回傳

void

---

setWidth()

setWidth(width): void

定義於: packages/board/src/input-interpretation/input-state-machine/kmt-input-context.ts:258

set the width of the canvas the width is synonymous with the canvas style width not the canvas width

參數

width

number

回傳

void

---

subscribe()

subscribe(observer, options?): () => void

定義於: packages/board/src/input-interpretation/input-state-machine/kmt-input-context.ts:227

參數

observer

Observer<[CanvasDimensions]>

options?

SubscriptionOptions

回傳

(): void

回傳

void

實作了

Observable.subscribe

---

tearDown()

tearDown(): void

定義於: packages/board/src/input-interpretation/input-state-machine/kmt-input-context.ts:322

Cleanup method to dispose of resources and event listeners

回傳

void

實作了

Canvas.tearDown