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ScaleLineAdornmentLayer

Namespace: ThinkGeo.Core

The ScaleLineAdornmentLayer is a concrete class inherited from AdornmentLayer. The ScaleLineAdornmentLayer class allows you show a ScaleLine graphic on the map.

public class ScaleLineAdornmentLayer : AdornmentLayer

Inheritance objectLayerBaseLayerAdornmentLayerScaleLineAdornmentLayer

Remarks:

The ScaleLineAdornmentLayer of the map is a quick way to implement a ScaleLine. When doing this, we also have to add a ScaleLineAdornmentLayer to the map control.

Properties

DisplayUnitString

Gets the dictionary that defines the text drawn for each ScaleLine unit.

public Dictionary<string, string> DisplayUnitString { get; }

Property Value

Dictionary<string, string>

Remarks:

Each entry specifies the abbreviation for a unit of measure; for example, "m" for meters or "ft" for feet.

MaxBarLength

Gets or sets the MaxBarLength.

public float MaxBarLength { get; set; }

Property Value

float

Margin

Gets or sets the pixel margin applied when the scale line is anchored to the map edges.

public float Margin { get; set; }

Property Value

float

DisplayUnitLabel

Gets the dictionary that defines the text drawn for each ScaleLine unit.

public Dictionary<DistanceUnit, string> DisplayUnitLabel { get; }

Property Value

Dictionary<DistanceUnit, string>

Remarks:

Each entry specifies the abbreviation for a unit of measure; for example, "m" for meters or "ft" for feet.

UpdateWhilePanning

public bool UpdateWhilePanning { get; }

Property Value

bool

UnitSystem

Gets or sets the UnitSystem to be used for the ScaleLine.

public ScaleLineUnitSystem UnitSystem { get; set; }

Property Value

ScaleLineUnitSystem

Remarks:

By setting this property, you can control which units appear on the top and bottom of the ScaleLine.

TextStyle

Gets or sets the TextStyle.

public TextStyle TextStyle { get; set; }

Property Value

TextStyle

AboveLabelTextStyle

Gets or sets the text style used to draw the label above the scale line.

public TextStyle AboveLabelTextStyle { get; set; }

Property Value

TextStyle

BelowLabelTextStyle

Gets or sets the text style used to draw the label below the scale line.

public TextStyle BelowLabelTextStyle { get; set; }

Property Value

TextStyle

Pen

Gets or sets the pen used to draw the ScaleLine segments.

public GeoPen Pen { get; set; }

Property Value

GeoPen

HaloPen

Gets or sets the halo pen that draws the outer line behind the ScaleLine.

public GeoPen HaloPen { get; set; }

Property Value

GeoPen

Width

Gets or sets the adornment width in pixels. Deprecated; use .

public float Width { get; set; }

Property Value

float

ResizeScale

Gets or sets the resize scale applied to the adornment layer.

public float ResizeScale { get; set; }

Property Value

float

Remarks:

A value of 1 preserves the original size; values greater than 1 enlarge; values less than 1 shrink.

Height

Gets or sets the adornment height in pixels. Deprecated; use .

public float Height { get; set; }

Property Value

float

DragMode

Gets or sets how the adornment responds to drag operations.

public AdornmentDragMode DragMode { get; set; }

Property Value

AdornmentDragMode

ResizeMode

public AdornmentResizeMode ResizeMode { get; set; }

Property Value

AdornmentResizeMode

BackgroundMask

Gets or sets the fill/outline style drawn behind the adornment content.

public AreaStyle BackgroundMask { get; set; }

Property Value

AreaStyle

Location

This property gets and sets the drawing location of the AdornmentLayer.

public AdornmentLocation Location { get; set; }

Property Value

AdornmentLocation

XOffsetInPixel

This property gets and sets the X pixel offset for the AdornmentLayer.

public float XOffsetInPixel { get; set; }

Property Value

float

Remarks:

This property allows you to specify an X offset. It is useful, when combined with a Y offset, to do things like modify the location of the adornment.

YOffsetInPixel

This property gets and sets the Y pixel offset for the AdornmentLayer.

public float YOffsetInPixel { get; set; }

Property Value

float

Remarks:

This property allows you to specify a Y offset. It is useful, when combined with an X offset, to do things like modify the location of the adornment.

RequestDrawingInterval

Gets or sets the interval between automatic draw requests. Obsolete.

public TimeSpan RequestDrawingInterval { get; set; }

Property Value

TimeSpan

Name

Gets or sets the display name for the layer.

public string Name { get; set; }

Property Value

string
The name used to identify the layer within UI components such as legends.

Remarks:

The name is user defined. Assign a descriptive value so tooling such as legends and layer lists can surface a meaningful label to end users.

IsOpen

Gets a value indicating whether the layer is currently open.

public bool IsOpen { get; }

Property Value

bool
true if the layer has completed its open routine; otherwise, false.

Remarks:

This method is the concrete wrapper for the abstract method IsOpenCore. Various methods on the Layer require that it be in an open state. If one of those methods is called when the state is not open, then the method will throw an exception. To enter the open state, you must call the Layer Open method. The method will raise an exception if the current Layer is already open.

As this is a concrete public method that wraps a Core method, we reserve the right to add events and other logic to pre- or post-process data returned by the Core version of the method. In this way, we leave our framework open on our end, but also allow you the developer to extend our logic to suit your needs. If you have questions about this, please contact our support team as we would be happy to work with you on extending our framework.

IsVisible

Gets or sets a value indicating whether the layer is visible.

public bool IsVisible { get; set; }

Property Value

bool
true to draw the layer; otherwise, false.

Remarks:

If this property is set to false, the layer will not draw. We ensure this in the Draw method. This is useful for legends and other controls that control the visibility of layers.

DrawingTime

Gets the last recorded drawing time for the layer.

public TimeSpan DrawingTime { get; protected set; }

Property Value

TimeSpan
The duration of the most recent draw operation.

Remarks:

We track the drawing time for the layer and report it back in this method. This is useful for determining the speed of various layers.

Projection

Gets the projection of the layer.

public Projection Projection { get; set; }

Property Value

Projection

DrawingExceptionMode

Gets or sets how drawing exceptions are handled when the layer renders.

public DrawingExceptionMode DrawingExceptionMode { get; set; }

Property Value

DrawingExceptionMode

Background

Gets or sets the background color used when rendering the layer.

public GeoColor Background { get; set; }

Property Value

GeoColor
The fill applied to areas not covered by layer content.

Transparency

Gets or sets the amount of transparency applied to the rendered image.

public float Transparency { get; set; }

Property Value

float
A value between 0 (fully transparent) and 255 (fully opaque).

BlueTranslation

Gets or sets the intensity adjustment applied to the blue channel.

public float BlueTranslation { get; set; }

Property Value

float
A value between -255 and 255 representing the blue channel translation.

RedTranslation

Gets or sets the intensity adjustment applied to the red channel.

public float RedTranslation { get; set; }

Property Value

float
A value between -255 and 255 representing the red channel translation.

GreenTranslation

Gets or sets the intensity adjustment applied to the green channel.

public float GreenTranslation { get; set; }

Property Value

float
A value between -255 and 255 representing the green channel translation.

KeyColors

Gets the collection of key colors that should be rendered as transparent.

public Collection<GeoColor> KeyColors { get; }

Property Value

Collection<GeoColor>

Remarks:

Attempting to access this collection when the associated GeoCanvas does not support key colors (see GeoCanvas.SupportKeyColor) results in an exception. Add colors to this collection to ensure they render as transparent.

IsNegative

Gets or sets a value indicating whether the image should be rendered with inverted colors.

public bool IsNegative { get; set; }

Property Value

bool
true to invert the color channels; otherwise, false.

IsGrayscale

Gets or sets a value indicating whether the image should be converted to grayscale prior to rendering.

public bool IsGrayscale { get; set; }

Property Value

bool
true to apply a grayscale filter; otherwise, false.

HasBoundingBox

Gets a value indicating whether the layer supports retrieving its bounding box.

public bool HasBoundingBox { get; }

Property Value

bool

Remarks:

When this property is false, calls to or GetFullExtent throw an exception. The default implementation returns false.

ThreadSafe

Gets or sets the threading guarantees provided by the layer implementation.

public ThreadSafetyLevel ThreadSafe { get; set; }

Property Value

ThreadSafetyLevel
The level of thread safety that callers can expect when interacting with the layer.

ColorMappings

Gets the color translation map that will be applied when rendering the layer.

public Dictionary<GeoColor, GeoColor> ColorMappings { get; }

Property Value

Dictionary<GeoColor, GeoColor>

WrappingMode

Gets or sets how the layer wraps when the map extent crosses world boundaries.

public WrappingMode WrappingMode { get; set; }

Property Value

WrappingMode

WrappingExtent

Gets or sets the geographic extent to use when wrapping is enabled.

public RectangleShape WrappingExtent { get; set; }

Property Value

RectangleShape

Constructors

ScaleLineAdornmentLayer()

Creates a new instance of the ScaleLineAdornmentLayer class. The default location of this ScaleLineAdornmentLayer is the lower left corner of the CurrentExtent of the map.

public ScaleLineAdornmentLayer()

ScaleLineAdornmentLayer(ScreenPointF)

Creates a new instance of the ScaleLineAdornmentLayer class by passing in the specified ScreenPoint, which will be the start position of this ScaleLineAdornmentLayer when it is shown on the map.

public ScaleLineAdornmentLayer(ScreenPointF startPoint)

Parameters

startPoint ScreenPointF
The start position of the ScaleLineAdornmentLayer that will be shown on the Map.

ScaleLineAdornmentLayer(AdornmentLocation)

Creates a new instance of the ScaleLineAdornmentLayer class by passing in the specified enumeration of the AdornmentLocation that will be used to set the start position of this ScaleLineAdornmentLayer when it is shown on the map.

public ScaleLineAdornmentLayer(AdornmentLocation location)

Parameters

location AdornmentLocation
This parameter specifies the location of the start point of the ScaleLineAdornmentLayer.

Methods

GetSelectionLocationCore(float, float, float, float)

Returns the selection origin for hit-testing.

protected ScreenPointF GetSelectionLocationCore(float mapWidth, float mapHeight, float adornmentWidth, float adornmentHeight)

Parameters

mapWidth float

mapHeight float

adornmentWidth float

adornmentHeight float

Returns

ScreenPointF

DrawCore(GeoCanvas, Collection<SimpleCandidate>)

This method draws the Layer.

protected void DrawCore(GeoCanvas canvas, Collection<SimpleCandidate> labelsInAllLayers)

Parameters

canvas GeoCanvas
This parameter is the view object or a NativeImage to draw on.

labelsInAllLayers Collection<SimpleCandidate>
This parameter represents the labels used for collision detection and duplication checking.

Returns

void
None

Remarks:

This abstract method is called from the concrete public method Draw. This method draws the representation of the layer based on the extent you provided.

When implementing this abstract method, consider each feature and its column data values. You can use the full power of the GeoCanvas to do the drawing. If you need column data for a feature, be sure to override the GetRequiredColumnNamesCore and add the columns you need to the collection. In many of the styles, we add properties to allow the user to specify which field they need; then, in the GetRequiredColumnNamesCore, we read that property and add it to the collection.

GetWidthCore()

Returns the last drawn width for selection and hit-testing.

protected float GetWidthCore()

Returns

float

GetHeightCore()

Returns the last drawn height for selection and hit-testing.

protected float GetHeightCore()

Returns

float

OpenCore()

Provides the overridable implementation that opens the instance and initializes the resources it depends on.

protected void OpenCore()

Returns

void

CloseCore()

Provides the overridable implementation that closes the instance and releases any resources it holds.

protected void CloseCore()

Returns

void

Events

DrawingProgressChanged

Occurs as the layer reports drawing progress (useful for async or tiled rendering scenarios).

public event EventHandler<DrawingProgressChangedEventArgs> DrawingProgressChanged;

RequestedDrawing

Raised after the drawing buffer elapses so consumers can handle a legacy drawing cycle. Obsolete.

public event EventHandler<RequestedDrawingLayerEventArgs> RequestedDrawing;

RequestingDrawing

Raised before the drawing buffer elapses so consumers can cancel a legacy drawing operation. Obsolete.

public event EventHandler<RequestingDrawingLayerEventArgs> RequestingDrawing;

DrawingException

Occurs when the DrawingException event is raised.

public event EventHandler<DrawingExceptionLayerEventArgs> DrawingException;

DrawnException

Occurs when the DrawnException event is raised.

public event EventHandler<DrawnExceptionLayerEventArgs> DrawnException;