The method includes: in a projection scenario, a first device displays, in a first display area of a display, a first user interface of a first application running on the first device, and displays, in a second display area of the display, a second user interface that is being displayed by a second device. The second user interface includes one or more file objects. A user may drag a first file object on the second user interface to the first user interface to release, so that the second device transfers the first file object to the first device. Then, the first device stores the first file object, and provides the first file object for the first application for processing. In embodiments, application data of one device can be directly shared to an application of another device without switching a user interface for a plurality of times.