iPhone CorePlot:error- "CPBarPlotFieldBarLength:" Undeclared

Hi I am trying to implement core plot in My iPhone App

for that I 开发者_StackOverflow社区use the below code

 -(NSNumber *)numberForPlot:(CPPlot *)plot 
                  field:(NSUInteger)fieldEnum recordIndex:(NSUInteger)index 
 { 
     if (plot.identifier==@"myBarChart") { 
         switch ( fieldEnum ) { 
             case CPBarPlotFieldBarLocation: 
                return (NSDecimalNumber *)[NSDecimalNumber numberWithUnsignedInteger:index]; 
             case CPBarPlotFieldBarLength: 
                 return [self.lockedPercentage objectAtIndex:index]; 
        } 

}

if I use this code in original coreplot code example it works fine for barchart but When I use same code in my App it is giving error

   case CPBarPlotFieldBarLength:Undeclared

What Could be the problem??

Please Help and Suggest

Thanks

CPBarPlotFieldBarLength has been renamed to CPBarPlotFieldBarTip.