A needle is used to point to the current value of a circular scale. An instance of an arc scale needle is represented by the ArcScaleNeedle object. It can be accessed as an item of the ArcScaleNeedleCollection object returned by the ArcScale.Needles property.
A typical arc scale needle is shown in the image below:
For more information on needles, refer to the Needle document.
Example
This example illustrates how to create a CircularGaugeControl instance with a single ArcScale object.
| MainWindow.xaml |
<Window x:Class="DXGauges_Circular.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:dxga="http://schemas.devexpress.com/winfx/2008/xaml/gauges"
Title="MainWindow" Height="350" Width="525">
<Grid>
<dxga:CircularGaugeControl Name="circularGaugeControl1" >
<dxga:CircularGaugeControl.Model>
<dxga:CircularRedClockModel />
</dxga:CircularGaugeControl.Model>
<dxga:CircularGaugeControl.Scales>
<dxga:ArcScale StartValue="0" EndValue="12"
StartAngle="-90" EndAngle="270"
MajorIntervalCount="12" MinorIntervalCount="5">
<dxga:ArcScale.LabelOptions>
<dxga:ArcScaleLabelOptions ShowFirst="False" Orientation="LeftToRight" />
</dxga:ArcScale.LabelOptions>
<dxga:ArcScale.Needles>
<dxga:ArcScaleNeedle Value="3" />
<dxga:ArcScaleNeedle Value="12" />
</dxga:ArcScale.Needles>
<dxga:ArcScale.Markers>
<dxga:ArcScaleMarker Value="7" />
</dxga:ArcScale.Markers>
<dxga:ArcScale.RangeBars>
<dxga:ArcScaleRangeBar AnchorValue="7" Value="3" />
</dxga:ArcScale.RangeBars>
<dxga:ArcScale.Layers>
<dxga:ArcScaleLayer />
</dxga:ArcScale.Layers>
<dxga:ArcScale.Ranges>
<dxga:ArcScaleRange StartValue="0" EndValue="4" />
<dxga:ArcScaleRange StartValue="4" EndValue="8" />
<dxga:ArcScaleRange StartValue="8" EndValue="12" />
</dxga:ArcScale.Ranges>
</dxga:ArcScale>
</dxga:CircularGaugeControl.Scales>
</dxga:CircularGaugeControl>
</Grid>
</Window>
|
System.Object
System.Windows.Threading.DispatcherObject
System.Windows.DependencyObject
System.Windows.Freezable
GaugeDependencyObject
ValueIndicatorBase
ArcScaleIndicator
ArcScaleNeedle