org.opengis.feature.display.canvas
Interface FeatureLayer


public interface FeatureLayer

Abstract base class for a grouping of features drawn on a Canvas. Each instance of this interface has a reference to a collection of features to draw and a style to draw those features with. Also, each FeatureLayer has a Z-order value that indicates the order in which features are drawn on the FeatureCanvas. Lower numbers draw first.

The current style and the Z-order are changeable at runtime, so consumers of FeatureLayer objects must add listeners to know if they have been changed.

Since:
GeoAPI 2.0

Method Summary
 void addFeatureLayerListener(FeatureLayerListener ll)
          Allows an object to register for events when one of the mutable properties of this layer has changed.
 FeatureCollection getFeatureCollection()
          Returns the collection of features that will be portrayed in this layer.
 double getLevel()
          Returns the current z-order level of this layer.
 double getMaximumLevel()
          Returns the maximum z-order level that this layer can be moved to.
 double getMinimumLevel()
          Returns the minimum z-order level that this layer can be moved to.
 FeatureStyle getStyle()
          Returns the style to apply to features in this layer.
 void removeFeatureLayerListener(FeatureLayerListener ll)
          Removes a listener that was previously added with the addFeatureLayerListener(ll) method.
 void setLevel(double level)
          Sets the current z-order level of this layer.
 void setStyle(FeatureStyle style)
          Sets the style that will be applied to features in this layer.
 

Method Detail

getFeatureCollection

FeatureCollection getFeatureCollection()
Returns the collection of features that will be portrayed in this layer. A null value is allowed and indicates that nothing will be drawn.


getStyle

FeatureStyle getStyle()
Returns the style to apply to features in this layer. A null value is allowed, and indicates that the features should not be drawn.


setStyle

void setStyle(FeatureStyle style)
Sets the style that will be applied to features in this layer.


getMinimumLevel

double getMinimumLevel()
Returns the minimum z-order level that this layer can be moved to.


getMaximumLevel

double getMaximumLevel()
Returns the maximum z-order level that this layer can be moved to.


setLevel

void setLevel(double level)
              throws IllegalArgumentException
Sets the current z-order level of this layer.

Throws:
IllegalArgumentException - If the level is outside the allowable range.

getLevel

double getLevel()
Returns the current z-order level of this layer.


addFeatureLayerListener

void addFeatureLayerListener(FeatureLayerListener ll)
Allows an object to register for events when one of the mutable properties of this layer has changed. A FeatureCanvas may, for example, use this to receive notification when the style has changed.


removeFeatureLayerListener

void removeFeatureLayerListener(FeatureLayerListener ll)
Removes a listener that was previously added with the addFeatureLayerListener(ll) method.



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