Customize NSPredicate editor

Basic sample project is attached. 1. All text editors should take 100% of the available space. They must adapt width to fit when a user adds/removes rows (the remove button shows up when there is more than one row). 2. The leftmost dropdown must have a menu separator between the ‘any column’ and the rest of the columns. 3. When changing the leftmost dropdown, the value in the text field should stay the same (if the data type has not changed). Example, switching from first name to last name should keep the value. Switching from first name to age, should remove it.