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An Interactive Digital Guide Map of Dhaka City Base digital map of Dhaka City A copy of the Dhaka Guide Map was collected from the Survey of Bangladesh. The scale of the map is 1/20,000 or 5 cm to a kilometer. The following features were digitized:  The digitizing process has been carried out on-screen using scanned images of the paper base map as guides. Different features were digitized as separate themes shown in Fig. 1. After the digitization process, topology was created, errors were identified and corrected, and attribute data was added to each coverage. A number of Simple Macro Language routines were used to simplify the repetitive tasks.  Implementation of interactive functions Avenue is the customization and development environment for ArcView. It is an object oriented scripting language that is fully integrated with ArcView. With it one can perform the following tasks (ESRI, 1996, p. 1):
The search option is used to find a particular feature in a view. It gives a list of features and makes a theme, that the user specified from a list, active in the view and finds a feature. When a feature is found, ArcView selects it and pans the view so that the feature is in the center of the view. Features highlight on the view when they are selected and remain highlighted until a different selection is made, or until they are deselected. By default, selected features highlight in yellow and zooms to the spatial extent. Search is a quick way to select a particular feature of interest. The Hotlink tool enables the features of a view to link with different objects. Hotlink helps accessing of virtually any data or application directly from a view. For example, one might click on a building to display its floor plan, click on a land parcel to review its legal documents, or click on a country to play a video about it. A hot link is followed when a feature in a theme is clicked with the Hot Link tool. To see a feature’s images and descriptions the user has to locate that feature with the help of search function. Incorporation of the digital map with the interactive functions In a graphical user interface (GUI), the digital map was incorporated with the interactive functions by creating new controls and adding them to the interface. Changes were made in the ArcView's interface for view document shown in Fig. 2. Two new controls were added to the interface - a Search button and a Display tool. The scripts for searching a feature and displaying graphics and text descriptions of features were assigned to the button’s 'Click' property and the tool’s 'Apply' property respectively. These two scripts were named as View.Highlight and View.Display respectively mentioned in Appendix. These controls were defined by giving icons and help messages. The 'S' icon for search function and the 'Frame Picture Icon' for display function were selected. When the cursor is placed over a button and a tool its function is indicated by a message displayed on the status bar. Searching a feature in a view To search a particular feature on a view the user has to get a list of names from which he will choose an option. Then the chosen option will be highlighted in the view. The user can find a feature in the following way:
Displaying images and information The action and the field are specified in the Hot Links panel of the Theme Properties dialog. Each theme in a view can have its own hot link definition. There is no default hot link definition. Hot links have to be defined before they can be used. Pathname of graphics and text has to be given in a specific field of the attribute table to access picture and information. If after clicking on a feature a beep sound occur it means that ArcView cannot find the application or file defined for that feature. The user can gain access to pictures and information of a particular feature in the following procedure:
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