The invention relates to a system for processing sliding operations on a portable terminal device. The portable terminal device includes a touch screen. The system includes a memory device configured to store data related to sliding operations, and a processor coupled to the memory device. The processor is configured to cause to display, on the touch screen, a communication function interface for receiving user sliding operations. The processor is further configured to receive original messages obtained on the touch screen corresponding to the user sliding operations, and process the original messages to determine possible sliding patterns corresponding to the user sliding operations. The processor is also configured to set a user-defined sliding pattern based on the possible sliding patterns.