AnnotationCollection Class

Represents a collection that stores annotations of a chart, pane or series point.

Namespace: DevExpress.XtraCharts

Assembly: DevExpress.XtraCharts.v20.1.dll

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

Declaration

C#

public class AnnotationCollection :
    ChartCollectionBase,
    IAnnotationCollection

VB.NET

Public Class AnnotationCollection
    Inherits ChartCollectionBase
    Implements IAnnotationCollection

Related API Members

The following members return AnnotationCollection objects:

Library	Related API Members
Cross-Platform Class Library	SeriesPoint.Annotations
	XYDiagramPaneBase.Annotations
WinForms Controls	ChartControl.Annotations
	SnapChart.Annotations
Reporting	XRChart.Annotations
ASP.NET Web Forms Controls	ChartControlSettings.Annotations
	WebChartControl.Annotations

Remarks

An object of the AnnotationCollection type is returned by the ChartControl.Annotations (WebChartControl.Annotations), XYDiagramPaneBase.Annotations and SeriesPoint.Annotations properties.

All annotations that are present in a chart control for any of its elements are stored in its AnnotationRepository object, returned by the ChartControl.AnnotationRepository (WebChartControl.AnnotationRepository) property.

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.

Note

A complete sample project is available at https://github.com/DevExpress-Examples/how-to-accompany-a-chart-its-pane-or-series-point-by-text-or-image-annotations-e2188

Form1.cs

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;
        }

Form1.vb

Imports System
Imports System.Drawing
Imports System.Windows.Forms
Imports DevExpress.XtraCharts
' ...
        Private Sub Form1_Load(ByVal sender As Object, ByVal e As EventArgs) Handles MyBase.Load
            ' 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.
            CType(chartControl1.Annotations(0).AnchorPoint, ChartAnchorPoint).X = 150
            CType(chartControl1.Annotations(0).AnchorPoint, ChartAnchorPoint).Y = 150

            ' Obtain the additional pane from the diagram's collection.
            Dim myPane As XYDiagramPaneBase = CType(chartControl1.Diagram, XYDiagram).Panes(0)

            ' And, position the chart's annotation in this pane's right top corner;
            CType(chartControl1.Annotations(0).ShapePosition, FreePosition).DockTarget = myPane
            CType(chartControl1.Annotations(0).ShapePosition, FreePosition).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).
            CType(myPane.Annotations(0).AnchorPoint, PaneAnchorPoint).AxisXCoordinate.AxisValue = 2
            CType(myPane.Annotations(0).AnchorPoint, PaneAnchorPoint).AxisYCoordinate.AxisValue = 180

            ' Position the annotation in relation to its anchor point.
            CType(myPane.Annotations(0).ShapePosition, RelativePosition).Angle = -135
            CType(myPane.Annotations(0).ShapePosition, RelativePosition).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).
            Dim myTextAnnotation As TextAnnotation = CType(chartControl1.AnnotationRepository.GetElementByName("Annotation 1"), TextAnnotation)
            Dim myImageAnnotation As ImageAnnotation = CType(chartControl1.AnnotationRepository.GetElementByName("Annotation 3"), ImageAnnotation)

            ' 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
        End Sub

Inheritance

Object

CollectionBase

ChartCollectionBase

AnnotationCollection