Skip to main content
A newer version of this page is available. .

AnnotationAnchorPoint Class

Represents a base class for classes representing annotation anchor point types.

Namespace: DevExpress.XtraCharts

Assembly: DevExpress.XtraCharts.v20.1.dll

NuGet Packages: DevExpress.Charts, DevExpress.WindowsDesktop.Charts

Declaration

public abstract class AnnotationAnchorPoint :
    ChartElement

The following members return AnnotationAnchorPoint objects:

Remarks

The AnnotationAnchorPoint class serves as a base for classes which provide functionality for annotation anchor points of different types (ChartAnchorPoint, PaneAnchorPoint and SeriesPointAnchorPoint).

For more information, refer to Annotations.

Example

This example demonstrates how text and image annotations can be created and anchored to a chart, pane or series point.

using System;
using System.Drawing;
using System.Windows.Forms;
using DevExpress.XtraCharts;
// ...
        private void Form1_Load(object sender, EventArgs e) {
            // Add a text annotation to the chart control's repository.
            chartControl1.AnnotationRepository.Add(new TextAnnotation("Annotation 1"));

            // And, assign a series point to the annotation's AnchorPoint property.
            // This adds the annotation to the series point's Annotations collection.
            chartControl1.AnnotationRepository[0].AnchorPoint =
                new SeriesPointAnchorPoint(chartControl1.Series[0].Points[2]);

            // Now, create an image annotation, and add it to the chart's collection.
            chartControl1.Annotations.AddImageAnnotation("Annotation 2",
                Bitmap.FromFile(@"...\...\image.png"));

            // Define the X and Y absolute coordinates for the annotation, in pixels.
            ((ChartAnchorPoint)chartControl1.Annotations[0].AnchorPoint).X = 150;
            ((ChartAnchorPoint)chartControl1.Annotations[0].AnchorPoint).Y = 150;

            // Obtain the additional pane from the diagram's collection.
            XYDiagramPaneBase myPane = ((XYDiagram)chartControl1.Diagram).Panes[0];

            // And, position the chart's annotation in this pane's right top corner;
            ((FreePosition)chartControl1.Annotations[0].ShapePosition).DockTarget = myPane;
            ((FreePosition)chartControl1.Annotations[0].ShapePosition).DockCorner = DockCorner.RightTop;

            // Another annotation is now being added to the collection of this pane.
            myPane.Annotations.AddImageAnnotation("Annotation 3", Bitmap.FromFile(@"...\...\image.png"));

            // Define its axis coordinates (in units appropriate for the scale type of the axes).
            ((PaneAnchorPoint)myPane.Annotations[0].AnchorPoint).AxisXCoordinate.AxisValue = 2;
            ((PaneAnchorPoint)myPane.Annotations[0].AnchorPoint).AxisYCoordinate.AxisValue = 180;

            // Position the annotation in relation to its anchor point.
            ((RelativePosition)myPane.Annotations[0].ShapePosition).Angle = -135;
            ((RelativePosition)myPane.Annotations[0].ShapePosition).ConnectorLength = 50;

            // You can get an annotation either via the collection of the element to which it is anchored,
            // or centrally, via the chart control's repository (e.g. by its name).
            TextAnnotation myTextAnnotation =
                (TextAnnotation)chartControl1.AnnotationRepository.GetElementByName("Annotation 1");
            ImageAnnotation myImageAnnotation =
                (ImageAnnotation)chartControl1.AnnotationRepository.GetElementByName("Annotation 3");

            // Define the text for the text annotation.
            myTextAnnotation.Text = "<i>Basic</i> <b>HTML</b> <u>is</u> <color=blue>supported</color>.";

            // Enable the interactive positioning for the image annotation.
            myImageAnnotation.RuntimeMoving = true;
            myImageAnnotation.RuntimeAnchoring = true;
            myImageAnnotation.RuntimeResizing = true;
            myImageAnnotation.RuntimeRotation = true;

            // Specify image annotation size mode.
            myImageAnnotation.SizeMode = ChartImageSizeMode.Tile;

            // And, adjust image annotation appearance options.
            myImageAnnotation.ShapeKind = ShapeKind.RoundedRectangle;
            myImageAnnotation.ShapeFillet = 10;
            myImageAnnotation.ConnectorStyle = AnnotationConnectorStyle.Arrow;
        }
See Also