I have a PDF that I have created that I am making into a editable form in Adobe Acrobat Pro I need to add a Calendar (Date Field) to it.
The option for the Date Field is there if I have a blank pdf in FormsCentral but is not there if I am using an existing pdf.
There's no built-in date picker in Acrobat forms. Some third-parties have developed their own pickers, namely FormRouter, Windjack and Max Wyss.
Some are free, others are not. Some are buggy, others less so. Some use fields, other dialogs. Do your research and decide which one is best for you.