Map Layer Hierarchy

Using the Map Builder > Getting to Know the Map Builder > Maps > Map Layer Hierarchy

Map Layer Hierarchy

As you import different data source types a layer hierarchy is built up consisting of layers and sublayers. Data sources of the same type are grouped as sublayers of a parent layer as shown for ESRI/Shape and GeoTIFF files in Figure 2.2.

The last layer in the hierarchy becomes the front layer in the Map View pane. For example, in Figure 2.2 the Labels layer is displayed in front of the GeoTIFF layer in the Map View pane.

You can rename layers and sublayers to make the name more meaningful, (see Renaming a Map Layer). For example, San Francisco Streets would be more meaningful than SF_Streets.shp.

Figure 2.2 Standard Layer Hierarchy

You can also set up your own layer hierarchy by creating new layers and sublayers, (see Creating a Map Layer Hierarchy). You can then fill them with one or more of the data sources you have already imported. Figure 2.3 shows an example of a new parent layer called Top Layer into which the SF_Streets.shp file has been placed.

Figure 2.3 Customized Layer Hierarchy

Map layers can also be hidden from the layer tree, (see Hiding and Showing a Map Layer). For example, in a case where end users can add more map layers to an application that has a fixed background map, the application developer may want to ensure that the end user cannot alter or remove this background map. The solution to this problem is to hide those layers from the tree so that they cannot be modified.

You also have the possibility to move layers to different positions in the hierarchy and to split layers or create filters on layers that contain metadata (see Splitting or Filtering a Map Layer). You can send layers to the front (top) or back (bottom) of the hierarchy, or change the position of a layer within the hierarchy.

The filtering mechanism allows you to create a layer that displays only the objects that match a filter. You can also split a layer by grouping together the objects that match the same value for selected metadata. In both cases, the split/filtered layers are added to the map layer hierarchy. Figure 2.4 shows an example of an ESRI/Shape file displayed according to a CONTINENT filter.

Figure 2.4 Split and Filtered Map Layers

A shortcut menu is available in the Map Layers pane that allows you to carry out most of the operations available in the Map Layers pane. For more information, see Managing Map Layers and Splitting or Filtering Map Layers.

PREVIOUS NEXT