Clear signature capture control doesn't clear signature image

[[email protected]]

Hi,

The image capture control has 2 states - canvas and image

Canvas is where you sign, image is what you see when you click the Accept button.

I have a signature capture control on an unbound UX and I am submitting the signature to a table using the Insert, Update, Delete action js. The problem I am having is that the signature control image is maintained after submit. This means that he next time the signature control is brought into view the previous signature is still visible when the signature control is in the image state.

I've worked out how to clear the canvas using {dialog.object}._functions._clearCanvas('SIGNATURECAPTURE'); which is the same as clicking the built in Clear button that comes with the signature control, but this only clears the canvas and not the image. If a user clicks the signature control Cancel button the previous image (i.e. signature) is still visible.

Is it possible to clear the image? Resetting the entire UX isn't an option in this case.

Thanks.

[Davidk]

Re: Clear signature capture control doesn't clear signature image

The signature image is just an image tag. And Alpha initializes that image with an blank image... base64.

Clearing the image tag... setting it to "" or "data:image/png;base64," doesn't really work because the size of the signature area gets messed up.

So... replace the image with the empty image that Alpha shoves in there. My Signature control is named "CUSTSIGNATURE".

{dialog.object}._functions._clearCanvas('CUSTSIGNATURE'); // case matters... must be uppercase
var sigObj = {dialog.Object}.getPointer('custSignature'); // case does not matter
sigObj.src = "data:image/png;base64,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";

Run your UX and Accept an empty Signature. Then inspect the Signature area and you'll see the base64 string that Alpha uses to fill that signature area with a blank image.

[[email protected]]

Re: Clear signature capture control doesn't clear signature image

The signature image is just an image tag. And Alpha initializes that image with an blank image... base64.

Clearing the image tag... setting it to "" or "data:image/png;base64," doesn't really work because the size of the signature area gets messed up.

So... replace the image with the empty image that Alpha shoves in there. My Signature control is named "CUSTSIGNATURE".

{dialog.object}._functions._clearCanvas('CUSTSIGNATURE'); // case matters... must be uppercase
var sigObj = {dialog.Object}.getPointer('custSignature'); // case does not matter
sigObj.src = "data:image/png;base64,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";

Run your UX and Accept an empty Signature. Then inspect the Signature area and you'll see the base64 string that Alpha uses to fill that signature area with a blank image.

[[email protected]]

Re: Clear signature capture control doesn't clear signature image

Thanks David, that works perfectly... and good to know what Alpha was doing here.