Custom Interval Types

RadTimeBar provides built-in support for a couple of predefined interval types ranging from milliseconds to centuries. For a full list of the predefined intervals, please refer to the Interval Formatters article. For all custom scenarios that the predefined intervals do not cover, the control supports custom interval type implementations.

Using Custom Interval Types

The Intervals collection contains items of type IntervalBase. That is why, in order to configure a RadTimeBar control to use a custom interval type, simply add an instance of that custom interval to the Intervals collection of the control.

The example below shows how you can add a custom interval type to the Intervals collection of a RadTimeBar control:

Adding a custom Interval to the Intervals collection of RadTimeBar

<telerik:RadTimeBar.Intervals> 
    <example:CustomInterval /> 
    <telerik:MonthInterval /> 
</telerik:RadTimeBar.Intervals> 

The IntervalBase class

A custom interval is a class that inherits the IntervalBase class and implements its abstract properties and methods:

• Formatters—Gets a collection of formatter that the interval can use to convert DateTime objects to strings.
• MinimumPeriodLength—Gets the smallest interval period.
• ExtractIntervalStart—Given a DateTime object, this method returns the start of the interval that contains the given DateTime object.
• IncrementByInterval—Given a DateTime object and span, this method increments the specified DateTime object by the specified number of MinimumPeriodLengths property.

Below you can find a sample custom interval implementation:

Creating a custom Interval

public class CustomInterval : IntervalBase 
{ 
    private static readonly Func<DateTime, string>[] formatters; 
 
    static CustomInterval() 
    { 
        formatters = new Func<DateTime, string>[] 
        { 
            date => string.Format("My custom interval {0}, {1}", GetNumberOfInterval(date), date.ToString("yyyy")), 
            date => string.Format("Custom interval {0}", GetNumberOfInterval(date)), 
            date => string.Format("C{0} {1}", GetNumberOfInterval(date), date.ToString("yyyy")), 
        }; 
    } 
 
    public override DateTime ExtractIntervalStart(DateTime date) 
    { 
        int firstMonthOfInterval = GetFirstMonthOfInterval(date); 
        return new DateTime(date.Year, firstMonthOfInterval, 1); 
    } 
 
    public override DateTime IncrementByInterval(DateTime date, int intervalSpan) 
    { 
        return date.AddMonths(intervalSpan * 6); 
    } 
 
    public override Func<DateTime, string>[] Formatters 
    { 
        get 
        { 
            return formatters; 
        } 
    } 
 
    public override TimeSpan MinimumPeriodLength 
    { 
        get 
        { 
            return TimeSpan.FromDays(180); 
        } 
    } 
 
    private static int GetNumberOfInterval(DateTime date) 
    { 
        int number = ((date.Month - 1) / 6) + 1; 
        return number; 
    } 
 
    private int GetFirstMonthOfInterval(DateTime date) 
    { 
        int quarter = GetNumberOfInterval(date); 
        int firstMonthOfInterval = ((quarter - 1) * 6) + 1; 
        return firstMonthOfInterval; 
    } 
} 

RadTimeBar with custom Interval

See Also

• Intervals Formatters
• Formatter Provider