Simple Labeling

Simple Labeling

The Simple Labeling specifies how features must be labeled.

Supported options are:

Property Description
LabelAttribute Specifies attribute name to be used as a source of labels.
LabelExpression Provides a way to customize and format label text. Overrides LabelAttribute
FontFamily Specifies font family to use to render text. The default is system dependent value.
FontStyle

Style to apply to text.

- FontStyle.Regular - regular text.

- FontStyle.Bold - bold text.

- FontStyle.Italic - italic text.

- FontStyle.Underine - underlined text.

- FontStyle.StrikeOut - text with a line through the middle.

FontSize Specifies size of the text.
FontColor Determines color of the text.
HaloSize Determines a size of the halo (or outline) around the text.
HaloColor Determines color of the halo around the text.
GeometryExpression Geometry expression to be used to transform geometries before passing it to the labeling engine.
MultipartMode

Specifies rendering behavior for multipart geometries.

- MultipartMode.All - place a label near every part of the geometry.

- MultipartMode.Any - place one label near any part of the geometry.

- MultipartMode.Largest - place a label near the largest part of the geometry.

Placement

Specifies how labels are placed relatively to the geometry.

- PointLabelPlacement - places label near the center of the geometry.

- LineLabelPlacement - places label along the geometry or its perimeter.

Priority Specifies priority of the label in case if it overlaps with other label.
The label with lower priority is not rendered. Default is 1000.

Examples

Points Labeling Examples

By default SimpleLabeling draws text over points:

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Here’s how to style font:

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In order to control text position relatively to point feature, placement property must be set:

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For more advanced scenarios, you might want to choose different labelings for features. Here’s how to do that:

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Lines Labeling Examples

By default SimpleLabeling draws label near center of the line:

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In order to rotate labels so they are parallel to lines, LineLabelPlacement with LineLabelAlignment.Parallel can be used:

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If you want texts to follow line precisely, LineLabelPlacement with LineLabelAlignment.Curved can be used:

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If you don’t want texts to overlap with line, use LineLabelPlacement.Offset:

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For more advanced scenarios, you might want to adjust the labels style dynamically based on feature attribute values. Here’s how to do that:

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