Resize Observer IDL

resizeobserver.d.ts

type ResizeObserverBoxOptions = "border-box" | "content-box" | "device-pixel-content-box";

interface ResizeObserverOptions {
    box?: ResizeObserverBoxOptions;
}

interface ResizeObservation {
    readonly lastReportedSizes: ReadonlyArray<ResizeObserverSize>;
    readonly observedBox: ResizeObserverBoxOptions;
    readonly target: Element;
}

declare var ResizeObservation: {
    prototype: ResizeObservation;
    new(target: Element): ResizeObservation;
};

interface ResizeObserver {
    disconnect(): void;
    observe(target: Element, options?: ResizeObserverOptions): void;
    unobserve(target: Element): void;
}

declare var ResizeObserver: {
    prototype: ResizeObserver;
    new(callback: ResizeObserverCallback): ResizeObserver;
};

interface ResizeObserverEntry {
    readonly borderBoxSize: ReadonlyArray<ResizeObserverSize>;
    readonly contentBoxSize: ReadonlyArray<ResizeObserverSize>;
    readonly contentRect: DOMRectReadOnly;
    readonly devicePixelContentBoxSize: ReadonlyArray<ResizeObserverSize>;
    readonly target: Element;
}

declare var ResizeObserverEntry: {
    prototype: ResizeObserverEntry;
    new(): ResizeObserverEntry;
};

interface ResizeObserverSize {
    readonly blockSize: number;
    readonly inlineSize: number;
}

declare var ResizeObserverSize: {
    prototype: ResizeObserverSize;
    new(): ResizeObserverSize;
};

interface ResizeObserverCallback {
    (entries: ResizeObserverEntry[], observer: ResizeObserver): void;
}

resizeobserver.widl

enum ResizeObserverBoxOptions {
    "border-box", "content-box", "device-pixel-content-box"
};

dictionary ResizeObserverOptions {
    ResizeObserverBoxOptions box = "content-box";
};

[Exposed=(Window)]
interface ResizeObserver {
    constructor(ResizeObserverCallback callback);
    void observe(Element target, optional ResizeObserverOptions options);
    void unobserve(Element target);
    void disconnect();
};

callback ResizeObserverCallback = void (sequence<ResizeObserverEntry> entries, ResizeObserver observer);

[Exposed=Window]
interface ResizeObserverEntry {
    readonly attribute Element target;
    readonly attribute DOMRectReadOnly contentRect;
    readonly attribute FrozenArray<ResizeObserverSize> borderBoxSize;
    readonly attribute FrozenArray<ResizeObserverSize> contentBoxSize;
    readonly attribute FrozenArray<ResizeObserverSize> devicePixelContentBoxSize;
};

interface ResizeObserverSize {
    readonly attribute unrestricted double inlineSize;
    readonly attribute unrestricted double blockSize;
};

interface ResizeObservation {
    constructor(Element target);
    readonly attribute Element target;
    readonly attribute ResizeObserverBoxOptions observedBox;
    readonly attribute FrozenArray<ResizeObserverSize> lastReportedSizes;
};