Theme-Based FOI Layers User-Defined FOI Layers

Oracle Maps 8-7 A map tile layer is usually associated with a MapViewer base map, and is managed by the MapViewer server. However, you can configure a map tile layer to cache map image tiles served by an external non-MapViewer map provider. The Oracle Maps client can also display a custom or built-in external tile layer served directly by an external tile server. The built-in Google Maps and Microsoft Bing Maps tile layers are examples. For more information, see Section 8.6, Built-in Map Tile Layers Google Maps and Bing Maps and the JavaScript API documentation for class MVGoogleTileLayer and MVBingTileLayer. If you need to overlay your own spatial data on top of the Google Maps or Bing Maps tile layer, see also Section 8.7, Transforming Data to a Spherical Mercator Coordinate System . Map tile layers are always placed at the bottom of the layer hierarchy. These layers display static and background map contents. When multiple such layers are included, they must all have the same coordinate system and zoom level definitions. Internally, the map tile layers are usually larger than the size of the map DIV container window. This allows additional tiles to be fetched and cached by the browser. As a result, these tiles will be immediately visible when the map layers are dragged around by the user.

8.1.3.2 Theme-Based FOI Layers

There can be one or more theme-based FOI layers. Each theme-based FOI layer consists of a collection of interactive FOIs that meet certain query criteria defined in a MapViewer predefined theme. FOIs can be points, lines, or polygons. For example, all stores with a sales volume greater than 100,000 can be displayed as a point theme-based FOI layer. Users can interact with the FOIs by moving the mouse over them or clicking on them. The application can customize how the map client reacts to such user interaction. All features geographic and non-geographic of a theme-based FOI layer are stored in the database. Features are queried and rendered by the FOI server when client applications request them. The query window for the theme-based FOI layers can be customized to be larger than the map DIV window, so that it gives some extra room for dragging the map without refreshing the theme-based FOI layers from server. For more information about theme-based FOI layers, see Section 8.3.1 .

8.1.3.3 User-Defined FOI Layers

A user-defined FOI is an interactive feature defined on the client side. The FOI can be a point, line, or polygon feature. Users can interact with a user-defined FOIs in the same way they can with a theme-based FOIs. However, in contrast with a theme-based FOI layer which is rendered as a collection of features, each user-defined FOI is requested and rendered individually. All attributes of the user-defined FOI, including the geometry representation and rendering style, must be provided by the application. For example, a route geometry based on user specified start and end addresses should be displayed as a user-defined line FOI on the map. The handling of user-defined FOI layers depends on Web browser in which the application is running: ■ With Microsoft Internet Explorer, all user-defined individual FOIs added by the application are placed inside a layer directly above the theme-based FOI layers. There can be at most one such layer. ■ With Opera and Mozilla-based browsers such as Netscape and Firefox, all user-defined individual FOIs are placed inside two layers, one for point features 8-8 Oracle Fusion Middleware Users Guide for Oracle MapViewer and the other for non-point features such as polylines and polygons. The non-point feature layer is placed under the point feature layer.

8.1.3.4 Information Window Layer