Design And Implementation Of Component Gis Map Display Module

Components Geography Information (ComGIS), a new technique based on Components Software, is the latest tendency of GIS technology. Based on the main idea of "The Map Display of ComGIS", the concept and technological foundation of ComGIS, the theory of Component (COM), and Component-based Development (CBD) are discussed separately in this paper; And some products of ComGIS in existence are studied. Also, system designs and development models of The Map Display of ComGIS have been presented based on recent practices, including the structure of data and map symbol library.Firstly, this paper emphasizes the great significance in the study of the map display component and its status in the PowerComMap (PCM). On the basis of analyzing the emergency, development and tendency of COM and ComGIS, and then discusses the great effects on the software development. In the second part, the basic theory and method about CBD is studied, and the component products in existence are analyzed in order to provide the idea for the design of map display. In the third part of this paper, the map display model, data structure, map symbol library, and system function of the Map Display system are designed with the direction of CBD theory; and finally, the map display objects classes are worked out with OO technology.In the forth part, the map display model is realized, and a sample-YunNan ecology system based on PCM is quoted, by which the advantage of COM GIS is proved. In the fifth part, the paper introduces the present work designing and testing of GPS function in PCM, presents the primary design of navigation Component Geography Information based on Windows CE operation system and GPS. At last, the whole paper is summed up.