Indicator Drag Tool

In This Topic

The indicator drag tool allows the user to change the value of gauge indicators interactively by pressing the mouse over the indicator and then dragging it.

In order to use the indicator drag tool you must create an instance of the NIndicatorDragTool object and add it to the control Tools collection:

C#	Copy Code
NThinChartControl1.Controller.Tools.Add(new NIndicatorDragTool());

Visual Basic	Copy Code
NThinChartControl1.Controller.Tools.Add(New NIndicatorDragTool())

Sometimes the gauge can contain many indicators and you may want to mark some of them as non draggable. This is achieved by setting the AllowDragging property of the respective indicator to false.

C#	Copy Code
someIndicator.AllowDragging = false;

Visual Basic	Copy Code
someIndicator.AllowDragging = False

Similarly to the other dragging tools - the indicator drag tool can invoke a callback when the value of the currently dragged indicator has changed. The following code snippet shows how to implement a simple gauge with a draggable indicator:

C#	Copy Code
public partial class _Default : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { if (!NThinChartControl1.Initialized) { NThinChartControl1.BackgroundStyle.FrameStyle.Visible = false; NThinChartControl1.Panels.Clear(); // set a chart title NLabel header = new NLabel(); NThinChartControl1.Panels.Add(header); // create the radial gauge NRadialGaugePanel radialGauge = new NRadialGaugePanel(); NThinChartControl1.Panels.Add(radialGauge); // add needle NNeedleValueIndicator needleIndicator = new NNeedleValueIndicator(); radialGauge.Indicators.Add(needleIndicator); header.Text = needleIndicator.Value.ToString(); // add drag tool NIndicatorDragTool indicatorDragTool = new NIndicatorDragTool(); indicatorDragTool.IndicatorDragCallback = new IndicatorDragCallback(); NThinChartControl1.Controller.Tools.Add(indicatorDragTool); } } [Serializable] class IndicatorDragCallback : INIndicatorDragCallback { #region INIndicatorDragCallback Members public void OnIndicatorValueChanged(NThinChartControl control, NGaugePanel gauge, NIndicator indicator, double oldValue, double newValue) { control.Labels[0].Text = indicator.Value.ToString(); } #endregion } }

Copy Code

public partial class _Default : System.Web.UI.Page

{

protected void Page_Load(object sender, EventArgs e)

{

if (!NThinChartControl1.Initialized)

{

NThinChartControl1.BackgroundStyle.FrameStyle.Visible = false;

NThinChartControl1.Panels.Clear();

// set a chart title

NLabel header = new NLabel();

NThinChartControl1.Panels.Add(header);

// create the radial gauge

NRadialGaugePanel radialGauge = new NRadialGaugePanel();

NThinChartControl1.Panels.Add(radialGauge);

// add needle

NNeedleValueIndicator needleIndicator = new NNeedleValueIndicator();

radialGauge.Indicators.Add(needleIndicator);

header.Text = needleIndicator.Value.ToString();

// add drag tool

NIndicatorDragTool indicatorDragTool = new NIndicatorDragTool();

indicatorDragTool.IndicatorDragCallback = new IndicatorDragCallback();

NThinChartControl1.Controller.Tools.Add(indicatorDragTool);

}

[Serializable]

class IndicatorDragCallback : INIndicatorDragCallback

{

#region INIndicatorDragCallback Members

public void OnIndicatorValueChanged(NThinChartControl control, NGaugePanel gauge, NIndicator indicator, double oldValue, double newValue)

{

control.Labels[0].Text = indicator.Value.ToString();

}

#endregion

}

Related Examples

Web Forms\ThinWeb\Indicator Drag Tool
Web Forms\ThinWeb\Custom Commands

Mvc\ThinWeb\Indicator Drag Tool