Symbian Os Environment, The Design And Realization Of The Instant Messaging Software

The number of mobile phone users in China has increased year by year, and the number of mobile Internet users is also increased steadily. In recent years, instant messaging products have the highest usage rate in mobile Internet applications, and the community to make friends develops rapidly. As the issuance of China's 3G (Third Generation) license, wireless Internet will grow explosiveiy, and its deeper applications will come out gradually in the 3G era, instant messaging products for mobile will also be further developed.Nowadays, people use instant messaging software for mobile mianly by GPRS (General Packet Radio Service) network, and users will pay for the service in accordance with the data flux. Due to the limitation of GPRS network bandwidth, text and picture are the main information for instant messaging. As audio and video interaction requires higher bandwidth, GPRS network can not provide good audio and video service. In this paper, we designed an instant messaging software for symbian moblie phone, which could provide text interaction, audio and video interaction, file transmission and other service by WiFi wireless network. As a result, we could reduce the network cost, and at the same time, we could get good audio and video interaction service.In chapter II of this article, we analyzed the need of instant messaging software for symbian mobile phone. According to the gole of the system, we analyzed the function demand of the client and server, and gave their use case model. After discussing the quality attributes such as extensibility and performance, we described the hardware and software platform of the software.In chapter III, we gave the the overall design of the system, and designed the framework of the software. First we gave the solution to the issues of communication means video compression, audio continuity, multi-thread, the stability of the software. Then, based on the analysis of demand, we gave the layered structure and the module of each layer, and discussed the function of each module; And next, we designed the logical structure of each module following to the form of UML class diagram, and discussed all the classes and their interface functions; Finally, we gave the workflow of the software.In chapter IV, we studied the key technologies to realize the software. We first analyzed the asynchronous service of Symbian OS (Operating System), and discussed how to use active scheduler and active object to achieve the asynchronous service; Then, we gave three method to prevent memory leak; Next, we payed more attention to study the function of managing video, capturing and playing audio, visiting file, WiFi communication and so on; Finally, we gave the way to design the software interface.In The 5th chapter, we gave the software test result. The result showed that we achieved our design gole, and we could connect to each other, interact by text mode or by audio and video mode, transmit files and so on between the two symbian mobile phone.In this paper, we designed and developed an instant messaging software for moblie phone of Symbian OS. By WiFi wireless network, the client and server mobile phones could communicate with each other to transmit text, audio data, video data, file data and so on. Users could use the software to interact by text mode or by audio and video mode, transmit files and so on.