IconValueStyle¶

Namespace: ThinkGeo.Core

This class allows you to choose different icons based on values in the data of a feature.

public class IconValueStyle : PositionStyle

Inheritance Object → Style → PositionStyle → IconValueStyle

Remarks:

When you create an IconValueStyle, you need to add multiple IconValueItems to its collection. You input the column name in the IconValueStyle and it will compare the data's value to each IconValueItem's FieldValue. If they match, then it will draw the Feature using the properties of the IconValueItem. In this way, you can render different data with different icons or text.

The MinimumLength and MaximumLength properties are important because they are used to ensure that a properly sized icon is used to draw things like road signs. For example, you can set the minimum and maximum values so that the sign icon for a single-digit road number uses one icon, while a two-digit road uses another, wider sign icon in a separate IconValueItem.

Properties¶

ColumnName¶

This property gets and sets the column name that will be used for the drawing and matching.

public string ColumnName { get; set; }

Property Value¶

String

        This property gets the column name that will be used for the drawing and
        matching.

Remarks:

This column name will be used to draw the text on the icon (if necessary) and to also match the value in the IconStyleItem.

IconValueItems¶

This property gets the collection of IconValueItems for matching.

public Collection<IconValueItem> IconValueItems { get; }

Property Value¶

Collection<IconValueItem>
This property gets the collection of IconValueItems for matching.

Remarks:

You should create your IconValueItems and place them in this collection for consideration.

PolygonLabelingLocationMode¶

This property gets and sets the mode that determines how to locate polygon's labeling

public PolygonLabelingLocationMode PolygonLabelingLocationMode { get; set; }

Property Value¶

PolygonLabelingLocationMode

        This property gets the mode that determines how to locate polygon's labeling

Remarks:

There are two ways to handle polygon's labeling location. The first is to use polygon's centroid as the labeling location, the second way is to use polygon's boungdingbox center as the labeling location.

MaxNudgingInPixel¶

public int MaxNudgingInPixel { get; set; }

Property Value¶

Int32

NudgingIntervalInPixel¶

public float NudgingIntervalInPixel { get; set; }

Property Value¶

Single

BestPlacementSymbolWidth¶

public float BestPlacementSymbolWidth { get; set; }

Property Value¶

Single

BestPlacementSymbolHeight¶

public float BestPlacementSymbolHeight { get; set; }

Property Value¶

Single

AbbreviationDictionary¶

public Dictionary<string, string> AbbreviationDictionary { get; set; }

Property Value¶

Dictionary<String, String>

LeaderLineStyle¶

public LineStyle LeaderLineStyle { get; set; }

Property Value¶

LineStyle

LeaderLineRule¶

public LabelLeaderLinesRule LeaderLineRule { get; set; }

Property Value¶

LabelLeaderLinesRule

LeaderLineMinimumLengthInPixels¶

public float LeaderLineMinimumLengthInPixels { get; set; }

Property Value¶

Single

GridSize¶

This property gets and sets the grid size used for deterministic labeling.

public int GridSize { get; set; }

Property Value¶

Int32
This property gets the grid sized used for deterministic labeling.

Remarks:

The grid size determines how many labels will be considered as candidates for drawing. The smaller the grid size, the higher the density of candidates. Making the grid size too small may have a performance impact.

DuplicateRule¶

This property gets and sets the rule that determines how duplicate labels are handled.

public LabelDuplicateRule DuplicateRule { get; set; }

Property Value¶

LabelDuplicateRule

        This property gets the rule that determines how duplicate labels are
        handled.

Remarks:

There are three ways to handle duplicate label names. The first is to suppress all duplicates, which means if there are two street segments with the same name then only one will be drawn. The second way is to suppress duplicate labels only if they are in one quarter of the screen. In this way, the screen will be divided into four quadrants, and if the two duplicate labels are in different quadrants, then they will both draw. The last way is to draw all duplicates.

OverlappingRule¶

This property gets and sets the rule that determines how overlapping labels are handled.

public LabelOverlappingRule OverlappingRule { get; set; }

Property Value¶

LabelOverlappingRule
This property gets the rule that determines overlapping labels are handled.

Remarks:

This defines the rules for label overlapping. Currently, either we allow overlapping or we do not. In the future, we may extend this to allow some percentage of partial overlapping.

AllowLabelNudging¶

public bool AllowLabelNudging { get; set; }

Property Value¶

Boolean

AllowLineCarriage¶

This property gets and sets whether the labeler will allow carriage returns to be inserted.

public bool AllowLineCarriage { get; set; }

Property Value¶

Boolean

        This property gets whether the labeler will allow carriage returns to be
        inserted.

Remarks:

This property enables the labeler to split long labels into multiple lines if need be. For instance, if you have a lake whose name is "Southern Homestead Lake," then the labeler may try and break the name onto multiple lines in order to better label the feature.

SuppressPartialLabels¶

This property gets and sets whether a partial label in the current extent will be drawn or not.

public bool SuppressPartialLabels { get; set; }

Property Value¶

Boolean

Remarks:

This property provides a solution to the "cut off" label issue in Map Suite Web Edition and Desktop Edition, which occurs when multiple tiles exist. When you set this property to true, any labels outside of the current extent will not be drawn.

ForceLineCarriage¶

This property gets and sets whether the labeler will force carriage returns to be inserted.

public bool ForceLineCarriage { get; set; }

Property Value¶

Boolean

        This property gets whether the labeler will force carriage returns to be
        inserted.

Remarks:

This property forces the labeler to split long labels into multiple lines. For instance, if you have a lake whose name is "Southern Homestead Lake," then the labeler will break the name onto multiple lines in order to better label the feature.

FittingPolygon¶

This property gets and sets whether the labeler will try to fit the label as best as it can within the boundary of a polygon.

public bool FittingPolygon { get; set; }

Property Value¶

Boolean

        This property gets whether the labeler will try to fit the label as best as
        it can within the boundary of a polygon.

Remarks:

None

LabelAllPolygonParts¶

This property gets and sets whether the labeler will label every part of a multi-part polygon.

public bool LabelAllPolygonParts { get; set; }

Property Value¶

Boolean

        This property gets whether the labeler will label every part of a multi-part
        polygon.

Remarks:

In some cases, you may want to label all of the parts of a multi-part polygon, while in other cases you may not. For example, you may have a series of lakes where you do want to label each polygon. In another case, you may have a country with many small islands and in this case you only want to label the largest polygon.

LabelAllLineParts¶

This property gets and sets whether the labeler will label every part of a multi-part line.

public bool LabelAllLineParts { get; set; }

Property Value¶

Boolean

        This property gets whether the labeler will label every part of a multi-part
        line.

Remarks:

In some cases, you may want to label all of the parts of a multi-part line, while in other cases you may not.

FittingPolygonFactor¶

This property gets and sets the factor to which it will keep the label inside of the polygon.

public double FittingPolygonFactor { get; set; }

Property Value¶

Double

        This property gets the factor to which it will keep the label inside of the
        polygon.

Remarks:

None

TextLineSegmentRatio¶

This property gets and sets the ratio required for the label length to match the line length.

public double TextLineSegmentRatio { get; set; }

Property Value¶

Double

        This property gets the ratio required for the label length to match the line
        length.

Remarks:

This allows you to suppress labels where the label length would greatly exceed the line length. For example, if you set the ratio to 1, then the label will be suppressed if it is longer than the line. If the ratio is lower, then the label would need to be shorter than the line. If higher, then the label is allowed to run past the length of the line. This allows you to control the look of things like road labeling.

TextPlacement¶

This property gets and sets the location of the label for point features relative to the point.

public TextPlacement TextPlacement { get; set; }

Property Value¶

TextPlacement

        This property gets the location of the label for point features relative to the
        point.

Remarks:

This property allows you to choose where the labels are created relative to the point. For example, you can set the property to RightCenter, which would ensure that all labels are placed to the right of and vertically centered with the point. Different kinds of point layers can be positioned differently. If the point layer is dense and position is not a main concern, then you can try the BestPlacement property. That property overrides this property and tries to fit the label in the best location so that the minimum number of labels are suppressed due to overlapping issues.

MaskType¶

public MaskType MaskType { get; set; }

Property Value¶

MaskType

TextContent¶

This property gives you the option to customize the labeling by using one or more columns. For example supposing I have 2 columns "ColumnA" and "ColumnB" with the values of "ValueA" and "ValueB", by setting this property to "{ColumnA} - {ColumnB}", it will draw "ValueA - ValueB" for the corresponding feature. Do remember to add the columns you want to draw (ColumnA and ColumnB in the case above) to RequiredColumnNames collection;

public string TextContent { get; set; }

Property Value¶

String

MaxAdjacentCharDeltaAngle¶

public double MaxAdjacentCharDeltaAngle { get; set; }

Property Value¶

Double

Name¶

This property gets and set the name of the style.

public string Name { get; set; }

Property Value¶

String
This property gets the name of the style.

Remarks:

This name is not used by the system; it is only for the developer. However, it can be used if you generate your own legend.

IsActive¶

This property gets and sets the active status of the style.

public bool IsActive { get; set; }

Property Value¶

Boolean
This property gets the active status of the style.

Remarks:

If the style is not active then it will not draw.

RequiredColumnNames¶

This property gets the collection of fields that are required for the style.

public Collection<string> RequiredColumnNames { get; }

Property Value¶

Collection<String>

        This property gets the collection of fields that are required for the
        style.

Remarks:

This property gets the collection of fields that are required for the style. These are in addition to any other columns you specify in styles that inherit from this one. For example, if you have use a ValueStyle and it requires a column name for the value comparison, then that column does not need to be in this collection. You only use the RequiredColumnNames for columns you need beyond those required by specific inherited styles.

Filters¶

public Collection<string> Filters { get; }

Property Value¶

Collection<String>

Constructors¶

IconValueStyle()¶

This is the constructor for the class.

public IconValueStyle()

Remarks:

If you use this constructor, then you need to set the required properties manually.

IconValueStyle(String)¶

This is the constructor for the class.

public IconValueStyle(string columnName)

Parameters¶

columnName String
This parameter is the column name you want to match on.

Remarks:

None

IconValueStyle(String, IEnumerable<IconValueItem>)¶

This is the constructor for the class.

public IconValueStyle(string columnName, IEnumerable<IconValueItem> iconValueItems)

Parameters¶

columnName String
This parameter is the column name you want to match on.

iconValueItems IEnumerable<IconValueItem>
This parameter is the icon value items you want to match on.

Remarks:

None

Methods¶

DrawCore(IEnumerable<Feature>, GeoCanvas, Collection<SimpleCandidate>, Collection<SimpleCandidate>)¶

This method draws the features on the view you provided.

protected void DrawCore(IEnumerable<Feature> features, GeoCanvas canvas, Collection<SimpleCandidate> labelsInThisLayer, Collection<SimpleCandidate> labelsInAllLayers)

Parameters¶

features IEnumerable<Feature>
This parameter represents the features you want to draw on the view.

canvas GeoCanvas
This parameter represents the view you want to draw the features on.

labelsInThisLayer Collection<SimpleCandidate>
The labels will be drawn in the current layer only.

labelsInAllLayers Collection<SimpleCandidate>
The labels will be drawn in all layers.

Exceptions¶

InvalidOperationException
In the event you attempt to call this method when the GeoCanvas's IsDrawing mode is false, it will throw an InvalidOperationException.

ArgumentNullException
If you pass a null as the view, we will throw an ArgumentNullException.

ArgumentNullException
If you pass a null as the features, we will throw an ArgumentNullException.

Remarks:

This overridden method is called from the concrete public method Draw. In this method, we take the features you passed in and draw them on the view you provided. Each style (based on its properties) may draw each feature differently.


When overriding this 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.

GetRequiredColumnNamesCore()¶

This method returns the column data for each feature that is required for the style to properly draw.

protected Collection<string> GetRequiredColumnNamesCore()

Returns¶

Collection<String>
This method returns a collection of the column names that it needs.

Exceptions¶

ArgumentNullException
If columnName is null, we will throw an ArgumentNullException.

Remarks:

This abstract method is called from the concrete public method GetRequiredFieldNames. In this method, we return the column names that are required for the style to draw the feature properly. For example, if you have a style that colors areas blue when a certain column value is over 100, then you need to be sure you include that column name. This will ensure that the column data is returned to you in the feature when it is ready to draw.

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.

GetLabelingCandidateCore(Feature, GeoCanvas, GeoFont, Single, Single, Double)¶

This method determines whether the specified feature is a good candidate to be labeled, based on the labeling properties set.

protected Collection<LabelingCandidate> GetLabelingCandidateCore(Feature feature, GeoCanvas canvas, GeoFont font, float xOffsetInPixel, float yOffsetInPixel, double rotationAngle)

Parameters¶

feature Feature

        This parameter is the feature that will be considered as a labeling
        candidate.

canvas GeoCanvas

        This parameter is the view that will be used to draw the feature. This method will not
        draw on this view, but rather will use it to determine font size, etc.

font GeoFont

xOffsetInPixel Single

yOffsetInPixel Single

rotationAngle Double

Returns¶

Collection<LabelingCandidate>

Remarks:

This overridden method is called from the concrete public method Draw. In this method, we take the feature you passed in and determine if it is a candidate for labeling. If it is, then we will add it to the return collection. The algorithm to determine whether the label will draw is complex and determined by a number of properties and factors.

Events¶

Formatting¶

public event EventHandler<FormattingPositionStyleEventArgs> Formatting;

Formatted¶

public event EventHandler<FormattedPositionStyleEventArgs> Formatted;