1 Column Control
Use the 1 Column control to place another control on its own line in the callout.
The 1 column control is only available in Grid callouts.
The 1 column control is located under Basic in the control menu.
Example
The callout below includes an input field and a button. The two controls are displayed next to each other in the callout preview.
By placing each of the two controls inside its own 1 column control, you can ensure that they will be displayed on separate lines.