Figure 5.2: Open file pop-up dialog. This dialog is used to select a data file. The Filter identifies the search mask for the files (i.e., all the *.dat files in the directory /data/wwingle/3d/plotgraph). Directories shows the directories immediately above or below the current directory. Files shows the files that satisfy the Filter. Selection can be used to type in a user specified entry, generally however, the user highlights the desired file in the Files list with the mouse pointer, then presses the Open button. Similar dialogs are also used for selecting add and save file names.