Date picker is input widget which have to be provided with an attribute to hold the value.
Hence, it's not possible to keep date attribute alone without attribute or data container.
Hope it help!
No this is not possible.
Mendix is object based and requires an object with an attribute to catch any value. In this case an DateTime attribute.
Incontradiction to traditional code development, you would create a page with input fields, send the entered values in a JSON or XML to the server and create a java object or alike based on this information. Within Mendix you need to create the Java object first and pass that to a dataview in a page. Where you can have the input widgets and connect those to members of the passed java object.