GaugeContext Class

Provides a connection between data item containers from the Gauges section and underlying control’s gauges.

Namespace: DevExpress.DashboardWin

Assembly: DevExpress.Dashboard.v24.2.Win.dll

Declaration

C#

public class GaugeContext :
    ControlContext

VB.NET

Public Class GaugeContext
    Inherits ControlContext

Related API Members

The following members return GaugeContext objects:

• DashboardItemControlEventArgs.GaugeContext

Remarks

A gauge context provides the connection between dashboard data item containers from the Gauges section and the underlying control’s elements (gauge elements, or gauges). The GetDashboardItemGauge method returns Gauge that corresponds to the specified gauge element. The GetControlGauges method, in turn, gets a collection of gauge elements (the CircularGauge or LinearGauge objects) that corresponds to the specified Gauge.

For example, the Gauge dashboard item has two data item containers (the Gauges section): Extended Price and Quantity. The OrderDate (Year) series contains three values: 2014, 2015, and 2016. The image below shows the Gauge’s elements that are used to define context:

When you pass the Extended Price data item container as the GetControlGauges method parameter, you get a collection of CircularGauge or LinearGauge elements that corresponds 2014, 2015, and 2016 values in return:

On the contrary, if you pass one of the CircularGauge or LinearGauge objects as the GetDashboardItemGauge method parameter, you get a Gauge object that corresponds to the opened data layer in the selected Gauge dashboard item:

The following code shows how to paint the tickmark text for circular gauges to red. The DashboardDesigner.DashboardItemControlUpdated event is used to update the Gauge’s appearance.

C#

using DevExpress.DashboardCommon;
using DevExpress.DashboardWin;
using DevExpress.XtraGauges.Core.Drawing;
using DevExpress.XtraGauges.Win.Gauges.Circular;

// ...

private void DashboardDesigner1_DashboardItemControlUpdated(object sender, DevExpress.DashboardWin.DashboardItemControlEventArgs e) {
    if(e.GaugeControl != null) {
        DashboardDesigner designer = (DashboardDesigner)sender;
        var gaugeDashboardItem = designer.Dashboard.Items[e.DashboardItemName] as GaugeDashboardItem;
        foreach(var dashGaugeElement in gaugeDashboardItem.Gauges) {
            var gaugeCollection = e.GaugeContext.GetGaugeControlGauges(dashGaugeElement);
            if(gaugeCollection != null) {
                for(int i = 0; i < gaugeCollection.Count; i++) {
                    CircularGauge gauge = gaugeCollection[i] as CircularGauge;
                    if(gauge != null)
                        gauge.Scales[0].AppearanceTickmarkText.TextBrush = new SolidBrushObject(Color.Red);
                }
            }
        }
    }
}

VB.NET

Imports DevExpress.DashboardCommon
Imports DevExpress.DashboardWin
Imports DevExpress.XtraGauges.Core.Drawing
Imports DevExpress.XtraGauges.Win.Gauges.Circular

' ...

Private Sub DashboardDesigner1_DashboardItemControlUpdated(ByVal sender As Object, ByVal e As DevExpress.DashboardWin.DashboardItemControlEventArgs)
    If e.GaugeControl IsNot Nothing Then
        Dim designer As DashboardDesigner = CType(sender, DashboardDesigner)
        Dim gaugeDashboardItem = TryCast(designer.Dashboard.Items(e.DashboardItemName), GaugeDashboardItem)
        For Each dashGaugeElement In gaugeDashboardItem.Gauges
            Dim gaugeCollection = e.GaugeContext.GetGaugeControlGauges(dashGaugeElement)
            If gaugeCollection IsNot Nothing Then
                For i As Integer = 0 To gaugeCollection.Count - 1
                    Dim gauge As CircularGauge = TryCast(gaugeCollection(i), CircularGauge)
                    If gauge IsNot Nothing Then
                        gauge.Scales(0).AppearanceTickmarkText.TextBrush = New SolidBrushObject(Color.Red)
                    End If
                Next i
            End If
        Next dashGaugeElement
    End If
End Sub

Inheritance

Object

ControlContext

GaugeContext