For any case of 'Add New', choose to open a new window (popup) for entering data.
It is better to open in a new form, reasons being:
- It is better for the user in terms of clarity. The change of view to data entry form can be a surprise
- It is better to code e.g. if you are using this control in a couple of places you may need to show or hide 'Save' buttons etc. Otherwise, it is a pain to make it behave differently in different contexts.
However, you do need to call back on save and requery it. Use a modal form and requery it (DON'T use JavaScript, instead use the Modal Popup Form Example) An example of this is in Outlook with the 'New' button.
