The Design And Implementation Of Photoviewer Based On OpenGL ES Under Android Platform

Nowadays, in the consumer goods market of smart phones, products whichinstalled with Android OS occupy a large proportion. When Android OS is verified canbe transplanted to Tablet PC, not only many hardware manufacturers favor the use ofAndroid OS, but also Google cooperation adds supporting for Tablet PC in the AndroidOS. With the diversification of Android applications, brilliant user interface experienceis also becoming increasingly popular, so Android OS is added with OpenGL ESgraphics library to comply with this demand. Based on these present situations, thispaper aims to implement a Tablet PC oriented PhotoViewer application with the use ofOpenGL ES to draw user interfaces.Based on the requirements analysis of this application, this paper designs anarthitecture which is based on data level and integrates display level and operationlevel, and designs and implements three functions of image data management, imagedata operation and user interface effects.The image data management plays a role to provide quick access to image file inorder to support the efficient operations of the image data; image data manipulationcontains the classification display of the virtual albums, image use setting, screenlocking, image scaling and image slide and settings. User interface effects cover screensensor effect, multi-point touch operation and application interface background setting.Besides, this application describes relationships between user interaction and interfacesswitching with a state machine model.The file cached two-level index is used to read images in this paper, the first levelindex is used to index image folders, and the second level index is used to indeximages. These indices will be written into storage disk, and be maintained when theapplication starts. The drawing of user interfaces uses the OpenGL ES graphics library.As to touch operations occured in the user interfaces, a touch event dispatcheringmechanism is used to ensure correct responds to user operations.Java and XML development language are used in this paper, and developmenttools are Eclipse IDE, Beyond Compare, Android SDK2.2, Android ADT plug-ins forEclipse. The PhotoViewer application developed in Ubuntu10.04developmentplatform is able to identify all image files in storage disk of a device, and then treate images folders which contain these imge files as a single set to build virtual albums,users can view image files through these virtual albums, and then perform functions ofvarious image operations.