Checkbox on Transaction record to indicate it has been printed

Hi All,

I've got a relatively simple project though I'm not sure whats the best practice for executing it. We want a checkbox on transaction records that becomes checked when a user prints the record. I couldn't do this with a workflow and I don't think I can add event listeners to the default print action - Which leads me to think I should create a custom button "Print Transaction" that can check the checkbox and calls the default print action. I would also have to hide the default print action to ensure the custom button will always trigger it. I'm thinking