Sorry for being slow getting back to you. A 'button' widget like you have described, as far as I know, does not exist. You will likely have to create your own(if you have not already). Reading our documentation on custom widgets should give you a fair start on how to pass resource into a widget and start reading and writing to them as needed.
Below is a custom widget that uses a slider to read and write to a single dataport, and hopefully should jump-start or at least serve as an example on how to do this in a custom widget:
Let us know if you have questions,