ArcUser Online

Making ARC Functions Easier with Arc Toolbox
Arc Toolbox contains over 140 geoprocessing tools presented as wizards and menu choices. Though most of these functions exist at the ARC command line, Arc Toolbox makes using them easier and more manageable. Arc Toolbox is organized into four main categories: Data Management Tools, Analysis Tools, Conversion Tools, and My Tools. An example of one of these tools is the overlay wizard, which steps the user through the process of setting up and running the UNION, INTERSECT, or IDENTITY commands on coverages that are selected by browsing or by dragging and dropping a selection from Arc Catalog.

The views panel displays selected items in the tree view. Tabs at the top of the views panel let users inspect the items in four different way--in contents, thumbnail, documentation, and preview modes. Selecting the contents view shows the feature data sets in a selected workspace or SDE database; the feature classes in a coverage; or the attribute items in a feature class, shapefile, or INFO table. The thumbnail view displays a graphical preview of a data set. These thumbnails are generated automatically for some data sets and can be created within Arc Catalog for other data sets. The documentation view lets the user create and display documentation (i.e., metadata) about the selected data set using Extended Markup Language (XML). XML documentation schemata can be built to conform to organizational documentation standards. Preview mode displays the selected data set and provides tools for zooming and panning.

The Data View and the Layout View provide two ways to view data in Arc Map. In the Data View users interact with the map without being concerned about page elements such as north arrows. The Layout View is a virtual page that includes cartographic elements and also shows all the data in data frames. Almost everything that can be done to data in the Data View can also be done in the Layout View. Right clicking on a data frame activates it, allowing the data inside to be manipulated. Both Data View and Layout View use the Table of Contents (TOC) to manage data. The TOC provides a legend-like display for the data sets in the map. The appearance of data sets can be changed through the TOC.

The TOC is also the interface to the layers of a map. Adding data to the Data View creates a layer for that data. A layer is not a copy of the data; it is a reference to the data. Layers contain information describing how the data should be drawn. Each layer can be assigned specific drawing characteristics. For example, a parcel coverage that is used by several groups within a planning department can have a layer made for each group. Each group can symbolize the layer its own way. Using layers, GIS managers or mapmakers can set up specific views of a data set that can be used for a mapmaking session. Data managers can protect the integrity of the original data set by allowing users to access only specific layers.

Data can be added to Arc Map by dragging and dropping it from Arc Catalog, by using the Add Data button on the Arc Map interface, or by right clicking on the TOC to bring up a context menu and using the Add Data option. The Add Data dialog, a lightweight version of the same dialog in Arc Catalog, illustrates the consistent interface design of these tools. Any of these methods of adding data will allow inclusion of all or selected portions of a data set. An entire coverage with all feature classes or just the lines and tics or specific feature classes from different data sets can be added--all at the same time. This simplifies and speeds up map creation.

Users can create, modify, and delete data as well as perform many other functions using the Editor toolbar. It offers more CAD-like functionality than previous versions of ArcInfo and allows precise adjustments and additions to data. Editor employs the concept of an edit sketch. The user digitizes a sketch of the points or vertices that make up a new feature. Once the process of edit sketch is started, the user can choose another command tool or perform another operation and then resume editing the sketch right where editing previously stopped. New construction tools allow the addition of features parallel or perpendicular to any other feature present on the map, and segments can be constrained to a specific length, radius, angle, or deflection angle. True curves, a much-requested feature, are available in Version 8 and can be created, edited, and maintained in Editor.

Editor also employs the concept of an edit task. Examples of edit tasks would be such activities as creating a new feature or extending or trimming a feature. Many other tools and functions are available in Editor.

The underlying foundation of Arc Catalog and Arc Map is Microsoft's Component Object Model (COM). COM is a coding standard for creating components and building applications from those components. It allows components to plug into other applications that support COM. For example, Visual Basic for Applications (VBA) is part of Arc Map and Arc Catalog. The VBA editor inside each of these applications lets users write custom scripts and run them as macros or save them in separate command buttons that can be added to the application interface. Customizations can be made outside Arc Map and Arc Catalog using development languages that support COM such as Visual C++, Delphi, or Java.