Properties of the layer of cataloged theme are accessible via the button 
or the menu command Edit+Properties, when a theme layer is selected in the navigation window. When browsing a theme the window “Layers of theme” should be opened and the same button or the menu command should be used.
The property sheet “Properties of layer” for a theme layer differs from analogous property sheet for a map layer.
Properties of the theme layer are shown on the following pages:
The page “General” contains the name of the layer itself, the name of the theme to which the layer belongs and also data on the original layer of a GDB component on the base of which this theme layer is built. The following origins can be indicated here:
a GDB map layer;
an EDB layer (see chapter 41 “Main EDB components”, subsection “EDB Layers”);
work layer of the theme.
For a work layer, the page “General” also contains the total number of features in the layer, and if the box Detail by feature types is checked – the list of feature types of the work layer and numbers of features of each type.
Page “Parameters” contains two checkboxes:
Selectable – the box is checked for those layers which features can be selected during browsing of the present theme.
Visible – if the box is cleared then the features of the present layer are not displayed when browsing this theme.
It should be remembered that managing indication of selectability and visibility can be performed not only on this property page but also in auxiliary window “Legend” (see chapter 12 “Themes”, subsection “Legend”).
Besides, the page contains a group of two checkboxes specifying modes of the layer caching (see chapter 12 “Themes”, subsection “Layer caching when displaying maps”):
Dynamically – switches the mode of putting into the cache buffer those features that are used in the operations of selecting and in the spatial filter conditions;
Preloading – switches the mode of loading all features of the layer into the cache buffer when the theme browsing window is opened.
The page “Styles” serves for specifying displaying styles of layer features. This page is absolutely identical to the similar page of the property sheet “Properties of layer” for a map layer. It should be remembered that according to the rules of inheritance, styles specified for a theme layer are used for displaying those features for which neither the styles of map feature type and theme feature type, nor the specific style of the feature is specified. At the same time theme layer styles override inherited styles of map layer.
The page “Scale zones” (figure 15-9) is present in the property sheet only in the case if scale zones are specified for the present theme.
Figure 15-9. Property sheet “Properties of layer”, page “Scale zones”
This page permits selection of styles of displaying layer features for every scale zone. In the upper part of the page there is a drop-down list containing all scale zones defined in theme properties (see “Theme properties”). For every zone the user can indicate if the present theme layer should be displayed with the scale falling into this zone (the box Visible) and what displaying styles should be used for the layer features. If the radio button Default is selected, in the present scale zone the style specified on page “Styles” will be inherited.
The page “Transformation” allows setting coordinate transformation of features which is performed when displaying the given theme layer. This page is similar to the page of the same name in theme properties (see subsection “Theme properties”).
If transformations both for theme layer and for theme in whole are set, the transformation of the layer will be performed on displaying.
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