The present invention provides a displaying system which is used for playing a first data flow or a second data flow, and the system comprises the following components: a decoder, for selectively decoding the first data stream to output a first decoded signal or the second data stream to output a second decoded signal according to a command signal; and a frame buffer, for receiving the first decoded signal or the second decoded signal to output a first video signal or a second video signal respectively; wherein when the decoder stops outputting the first decoded signal and starts outputting the second decoded signal, the frame buffer will buffer a last received frame of the first decoded signal, and when the decoder stops outputting the second decoded signal and starts outputting the first decoded signal, the frame buffer will buffer a last received frame of the second decoded signal. The displaying system of the invention can do switching between the area medium data flow and the broadcast data flow with only one decoder without the data loss. The character of time migration is used when the picture need not to be viewed the broadcast can be buffered thereby the displaying can beresumed at the condition that is data is not lost.