How to Retrieve and Set Colors from a Categorical Axis on a Visualization Using the Spotfire® C# API

Introduction

The following is a sample C# code which illustrates how to retrieve and set a color for a specific category on a categorical axis, for a Line Chart visualization:

Code Sample

// Copyright © 2017. TIBCO Software Inc. Licensed under TIBCO BSD-style license.

public static void someMethodName(AnalysisApplication application)
{
    LineChart lc = application.Document.ActiveVisualReference.As<LineChart>();

    //Retrieve colors of a specific category
    int count = lc.ColorAxis.Coloring.AddCategoricalColorRule().GetExplicitCategories().Count;    
    IList<CategoryKey> myKeys = lc.ColorAxis.Coloring.AddCategoricalColorRule().GetExplicitCategories();    
    List<string> categoryKeyNames = new List<string>();
    List<string> colors = new List<string>();
    foreach (CategoryKey key in myKeys)
    {
	categoryKeyNames.Add(key.ToString());
        colors.Add(lc.ColorAxis.Coloring.GetColorForCategory(key).ToString());
    }
    MessageBox.Show("number of categories found:" + count + "n categories:" + categoryKeyNames[0] + "-" + colors[0]);
    
	//Set color for a specific category
    string hexValue = "#DAA520"; // You do need the hash, [goldenrod color] 
    System.Drawing.Color colour = System.Drawing.ColorTranslator.FromHtml(hexValue);
    lc.ColorAxis.Coloring.SetColorForCategory(myKeys[1], colour);           
}

References

• API Reference: Visual
• API Reference: Coloring
• API Reference: Categorical Color Rule
• API Reference: CategoryKey

License:  TIBCO BSD-Style License