1. A computer-implemented method of assisting a user to create a user interface (UI), comprising: receiving an incomplete UI design, the incomplete UI design comprising a first set of one or more existing UI components; identifying a plurality of example designs, each comprising a second set of one or more corresponding UI components, similar to the first set, and one or more additional UI components, wherein identifying comprises calculating a transformation cost associated with each of the plurality of example designs; grouping the plurality of example designs into a plurality of groups based on similarities between the additional UI components thereof; ranking the plurality of groups based on a number of example designs therein; selecting, from each group, a representative example design; and providing the representative example designs for presentation to the user in an order based on the ranking, wherein presenting includes providing user controls for the selection of a specific example design for incorporation with the incomplete UI design.