MGLFillStyleLayer


@interface MGLFillStyleLayer : MGLVectorStyleLayer

An MGLFillStyleLayer is a style layer that renders one or more filled (and optionally stroked) polygons on the map.

Use a fill style layer to configure the visual appearance of polygon or multipolygon features. These features can come from vector tiles loaded by an MGLVectorTileSource object, or they can be MGLPolygon, MGLPolygonFeature, MGLMultiPolygon, or MGLMultiPolygonFeature instances in an MGLShapeSource or MGLComputedShapeSource object.

You can access an existing fill style layer using the -[MGLStyle layerWithIdentifier:] method if you know its identifier; otherwise, find it using the MGLStyle.layers property. You can also create a new fill style layer and add it to the style using a method such as -[MGLStyle addLayer:].

See the Select a feature within a layer example to learn how to use a TERNARY expression to modify the fillOpacity of an MGLFillStyleLayer object. See the Add a pattern to a polygon example to learn how to use an image to add pattern to the features styled by a MGLFillStyleLayer.

Example

let layer = MGLFillStyleLayer(identifier: "parks", source: parks)
layer.sourceLayerIdentifier = "parks"
layer.fillColor = NSExpression(forConstantValue: UIColor.green)
layer.predicate = NSPredicate(format: "type == %@", "national-park")
mapView.style?.addLayer(layer)
  • Returns a fill style layer initialized with an identifier and source.

    After initializing and configuring the style layer, add it to a map view’s style using the -[MGLStyle addLayer:] or -[MGLStyle insertLayer:belowLayer:] method.

    Declaration

    Objective-C

    - (nonnull instancetype)initWithIdentifier:(nonnull NSString *)identifier
                                        source:(nonnull MGLSource *)source;

    Swift

    init(identifier: String, source: MGLSource)

    Parameters

    identifier

    A string that uniquely identifies the source in the style to which it is added.

    source

    The source from which to obtain the data to style. If the source has not yet been added to the current style, the behavior is undefined.

    Return Value

    An initialized foreground style layer.

  • Sorts features in ascending order based on this value. Features with a higher sort key will appear above features with a lower sort key.

    You can set this property to an expression containing any of the following:

    • Constant numeric values
    • Predefined functions, including mathematical and string operators
    • Conditional expressions
    • Variable assignments and references to assigned variables
    • Interpolation and step functions applied to the $zoomLevel variable and/or feature attributes

    Declaration

    Objective-C

    @property (nonatomic, null_resettable) NSExpression *fillSortKey;

    Swift

    var fillSortKey: NSExpression! { get set }
  • Whether or not the fill should be antialiased.

    The default value of this property is an expression that evaluates to YES. Set this property to nil to reset it to the default value.

    This attribute corresponds to the fill-antialias layout property in the Mapbox Style Specification.

    You can set this property to an expression containing any of the following:

    • Constant Boolean values
    • Predefined functions, including mathematical and string operators
    • Conditional expressions
    • Variable assignments and references to assigned variables
    • Step functions applied to the $zoomLevel variable

    This property does not support applying interpolation functions to the $zoomLevel variable or applying interpolation or step functions to feature attributes.

    Declaration

    Objective-C

    @property (nonatomic, assign, unsafe_unretained, readwrite,
              getter=isFillAntialiased, null_resettable)
        NSExpression *fillAntialiased;

    Swift

    var fillAntialiased: NSExpression! { get set }
  • The color of the filled part of this layer.

    The default value of this property is an expression that evaluates to UIColor.blackColor. Set this property to nil to reset it to the default value.

    This property is only applied to the style if fillPattern is set to nil. Otherwise, it is ignored.

    You can set this property to an expression containing any of the following:

    • Constant UIColor values
    • Predefined functions, including mathematical and string operators
    • Conditional expressions
    • Variable assignments and references to assigned variables
    • Interpolation and step functions applied to the $zoomLevel variable and/or feature attributes

    Declaration

    Objective-C

    @property (nonatomic, null_resettable) NSExpression *fillColor;

    Swift

    var fillColor: NSExpression! { get set }
  • The transition affecting any changes to this layer’s fillColor property.

    This property corresponds to the fill-color-transition property in the style JSON file format.

    Declaration

    Objective-C

    @property (nonatomic) MGLTransition fillColorTransition;

    Swift

    var fillColorTransition: MGLTransition { get set }
  • The opacity of the entire fill layer. In contrast to the fillColor, this value will also affect the 1pt stroke around the fill, if the stroke is used.

    The default value of this property is an expression that evaluates to the float 1. Set this property to nil to reset it to the default value.

    You can set this property to an expression containing any of the following:

    • Constant numeric values between 0 and 1 inclusive
    • Predefined functions, including mathematical and string operators
    • Conditional expressions
    • Variable assignments and references to assigned variables
    • Interpolation and step functions applied to the $zoomLevel variable and/or feature attributes

    Declaration

    Objective-C

    @property (nonatomic, null_resettable) NSExpression *fillOpacity;

    Swift

    var fillOpacity: NSExpression! { get set }
  • The transition affecting any changes to this layer’s fillOpacity property.

    This property corresponds to the fill-opacity-transition property in the style JSON file format.

    Declaration

    Objective-C

    @property (nonatomic) MGLTransition fillOpacityTransition;

    Swift

    var fillOpacityTransition: MGLTransition { get set }
  • The outline color of the fill. Matches the value of fillColor if unspecified.

    This property is only applied to the style if fillPattern is set to nil, and fillAntialiased is set to an expression that evaluates to YES. Otherwise, it is ignored.

    You can set this property to an expression containing any of the following:

    • Constant UIColor values
    • Predefined functions, including mathematical and string operators
    • Conditional expressions
    • Variable assignments and references to assigned variables
    • Interpolation and step functions applied to the $zoomLevel variable and/or feature attributes

    Declaration

    Objective-C

    @property (nonatomic, null_resettable) NSExpression *fillOutlineColor;

    Swift

    var fillOutlineColor: NSExpression! { get set }
  • The transition affecting any changes to this layer’s fillOutlineColor property.

    This property corresponds to the fill-outline-color-transition property in the style JSON file format.

    Declaration

    Objective-C

    @property (nonatomic) MGLTransition fillOutlineColorTransition;

    Swift

    var fillOutlineColorTransition: MGLTransition { get set }
  • Name of image in sprite to use for drawing image fills. For seamless patterns, image width and height must be a factor of two (2, 4, 8, …, 512). Note that zoom-dependent expressions will be evaluated only at integer zoom levels.

    You can set this property to an expression containing any of the following:

    • Constant string values
    • Predefined functions, including mathematical and string operators
    • Conditional expressions
    • Variable assignments and references to assigned variables
    • Interpolation and step functions applied to the $zoomLevel variable and/or feature attributes

    Declaration

    Objective-C

    @property (nonatomic, null_resettable) NSExpression *fillPattern;

    Swift

    var fillPattern: NSExpression! { get set }
  • The transition affecting any changes to this layer’s fillPattern property.

    This property corresponds to the fill-pattern-transition property in the style JSON file format.

    Declaration

    Objective-C

    @property (nonatomic) MGLTransition fillPatternTransition;

    Swift

    var fillPatternTransition: MGLTransition { get set }
  • The geometry’s offset.

    This property is measured in points.

    The default value of this property is an expression that evaluates to an NSValue object containing a CGVector struct set to 0 points rightward and 0 points downward. Set this property to nil to reset it to the default value.

    This attribute corresponds to the fill-translate layout property in the Mapbox Style Specification.

    You can set this property to an expression containing any of the following:

    • Constant CGVector values
    • Predefined functions, including mathematical and string operators
    • Conditional expressions
    • Variable assignments and references to assigned variables
    • Interpolation and step functions applied to the $zoomLevel variable

    This property does not support applying interpolation or step functions to feature attributes.

    Declaration

    Objective-C

    @property (nonatomic, null_resettable) NSExpression *fillTranslation;

    Swift

    var fillTranslation: NSExpression! { get set }
  • The transition affecting any changes to this layer’s fillTranslation property.

    This property corresponds to the fill-translate-transition property in the style JSON file format.

    Declaration

    Objective-C

    @property (nonatomic) MGLTransition fillTranslationTransition;

    Swift

    var fillTranslationTransition: MGLTransition { get set }
  • Controls the frame of reference for fillTranslation.

    The default value of this property is an expression that evaluates to map. Set this property to nil to reset it to the default value.

    This property is only applied to the style if fillTranslation is non-nil. Otherwise, it is ignored.

    This attribute corresponds to the fill-translate-anchor layout property in the Mapbox Style Specification.

    You can set this property to an expression containing any of the following:

    • Constant MGLFillTranslationAnchor values
    • Any of the following constant string values:
      • map: The fill is translated relative to the map.
      • viewport: The fill is translated relative to the viewport.
    • Predefined functions, including mathematical and string operators
    • Conditional expressions
    • Variable assignments and references to assigned variables
    • Step functions applied to the $zoomLevel variable

    This property does not support applying interpolation functions to the $zoomLevel variable or applying interpolation or step functions to feature attributes.

    Declaration

    Objective-C

    @property (nonatomic, null_resettable) NSExpression *fillTranslationAnchor;

    Swift

    var fillTranslationAnchor: NSExpression! { get set }