Formatting Telerik Chart and Legend Labels in Silverlight
- by Bryan
I am trying to format a column called 'Month' using the 3-character month abbreviation in my data grid which is bound to a bar chart. My grid and chart are based on this demo example: http://demos.telerik.com/silverlight/#Chart/Aggregates. Basically, the grid compiles data and summarizes by Year, Quarter, Month, and then some other categories as well. For the Month column, I tried two different methods (for sorting purposes, I have to use an integer or some date value for the month). First, I just made Month an integer field and then used a converter mapped in the xaml for the 'Month' field to display 'JAN', 'FEB', etc. This worked fine for the grid, but the chart would display 1, 2, etc. instead of the month abbreviation. I researched this and was not able to come up with a solution to map the converter to the chart. So, I tried making the Month field a datetime and then set the value to 1/1/1900, 2/1/1900, etc. and specified the format of the field to 'MMM' in the xaml for the grid. I then used the following statement to set the the format in the chart when the user grouped by month:
SalesAnalysisChart.DefaultView.ChartArea.AxisX.DefaultLabelFormat = "MMM";
This partially worked in that when the months were displayed across the x-axis they were labeled properly, but not when they appeared in the legend (the user, of course, can group by any of the columns which may or may not include month). I've tried setting LegendItemLabelFormat, ItemLabelFormat, etc. but without success. I'm not sure of the element on which to set the property. I only need to change the default format for just the Month column - all other columns should display normally when grouped. I also came across a class called 'LegendItemFormatConverter' which looks promising but I can't find any examples as to how to implement it. I would actually prefer the converter method because the converter I wrote displays the month abbreviation in all caps, whereas the 'MMM' format displays in upper/lower case. Here is the converter code that I originally used for the grid:
using System;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Ink;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
using System.Windows.Data;
namespace ApolloSL
{
public class MonthConverter : IValueConverter
{
public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
{
if (value != null)
{
DateTime date = new DateTime(1900, (Int32)value, 1);
return date.ToString("MMM").ToUpper();
}
else
{ return ""; }
}
public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
{
return value.ToString();
}
}
}
Please help...
Thanks in advance for your assistance,
Bryan