Add TypeScript declaration file

[BlessMyCode]

Can you add a typeScript declaration file in the project plz?
like this #5 but an updated version

[agilgur5]

I don't have experience with TypeScript, so I'm not confident in my ability to maintain a declaration file at this time. If there were a contributor who could maintain it, then I'd be okay with that, but otherwise I think a third-party typing makes more sense at this time.

As signature_pad recently did a re-write to TypeScript, I would like to do that at some point as well (and could potentially re-use signature_pad's types that way), but I don't have a timeline for that right now.

[chillitom]

I've submitted a PR with definitions.

In the meantime I've dropped a file in my source repo SignatureCanvas.d.ts with the following definition:

declare module 'react-signature-canvas' {
    // signature_pad's props
    export interface IOptions {
        dotSize?: number | (() => number);
        minWidth?: number;
        maxWidth?: number;
        minDistance?: number;
        backgroundColor?: string;
        penColor?: string;
        throttle?: number;
        velocityFilterWeight?: number;
        onBegin?: (event: MouseEvent | Touch) => void;
        onEnd?: (event: MouseEvent | Touch) => void;
    }

    // props specific to the React wrapper
    export interface SignatureCanvasProps extends IOptions {
        canvasProps?: any;
        clearOnResize?: boolean;
    }

    export default class SignatureCanvas extends React.Component<SignatureCanvasProps> {}
}

[ksocha]

I've created a PR to DefinitelyTyped as discussed in #25

DefinitelyTyped/DefinitelyTyped#41396

[agilgur5]

@types/react-signature-canvas is now published thanks to @ksocha !! 🎉 🎉 This also has more specific types than the ones here (further improved version of my improvements in #25), re-uses types from @types/signature_pad, and has tests.
Please file any type issues with those unofficial third-party type definitions at DefinitelyTyped.

Will be locking this now as a tracking issue. A TS re-write is in progress (#25 (comment)) so official internal TS support is planned for the v1.1.x release of react-signature-canvas, at which point @types/react-signature-canvas will no longer be necessary and will be deprecated.