already_AddRefed<nsISupports> AnonymousContent::GetCanvasContext(
const nsAString& aElementId, const nsAString& aContextId,
ErrorResult& aRv) {
Element* element = GetElementById(aElementId);
if (!element) {
aRv.Throw(NS_ERROR_NOT_AVAILABLE);
return nullptr;
}
if (!element->IsHTMLElement(nsGkAtoms::canvas)) {
return nullptr;
}
nsCOMPtr<nsISupports> context;
HTMLCanvasElement* canvas = static_cast<HTMLCanvasElement*>(element);
canvas->GetContext(aContextId, getter_AddRefs(context));
return context.forget();
}
nsresult
HTMLCanvasElement::CopyInnerTo(Element* aDest)
{
nsresult rv = nsGenericHTMLElement::CopyInnerTo(aDest);
NS_ENSURE_SUCCESS(rv, rv);
if (aDest->OwnerDoc()->IsStaticDocument()) {
HTMLCanvasElement* dest = static_cast<HTMLCanvasElement*>(aDest);
dest->mOriginalCanvas = this;
nsCOMPtr<nsISupports> cxt;
dest->GetContext(NS_LITERAL_STRING("2d"), getter_AddRefs(cxt));
nsRefPtr<CanvasRenderingContext2D> context2d =
static_cast<CanvasRenderingContext2D*>(cxt.get());
if (context2d && !mPrintCallback) {
HTMLImageOrCanvasOrVideoElement element;
element.SetAsHTMLCanvasElement() = this;
ErrorResult err;
context2d->DrawImage(element,
0.0, 0.0, err);
rv = err.ErrorCode();
}
}
return rv;
}
