1. A wearable device, comprising: a microprocessor, a first switch, a Bluetooth element, and a multimedia element, wherein the Bluetooth element, the multimedia element, and the microprocessor are all connected to the first switch; the Bluetooth element is configured to send a switch request to the first switch according to a received scenario notification; the first switch is configured to selectively establish a data transmission connection between a) the Bluetooth element and the multimedia element, and b) a data transmission connection between the Bluetooth element and the microprocessor, according to the switch request; and the multimedia element is configured to store and play a multimedia file, and the microprocessor is configured to monitor and store data corresponding to a preset event; wherein the scenario notification is a preset-event occurrence notification sent by the microprocessor, and the switch request is a second switch request; a general purpose input/output (GPIO) connection is established between the Bluetooth element and the microprocessor; the microprocessor is configured to send the preset-event occurrence notification to the Bluetooth element using the GPIO connection when detecting that a preset event occurs; the Bluetooth element is configured to: receive the preset-event occurrence notification sent by the microprocessor, and send the second switch request to the first switch according to the preset-event occurrence notification; and the first switch is configured to establish the data transmission connection between the Bluetooth element and the microprocessor according to the second switch request.