在Objective-C ++类中实现Objective-C协议

Question

说我有Objective-C协议：

@protocol XYZPieChartViewDataSource
    - (NSUInteger)numberOfSegments;
    - (CGFloat)sizeOfSegmentAtIndex:(NSUInteger)segmentIndex;
    - (NSString *)titleForSegmentAtIndex:(NSUInteger)segmentIndex;
@end

我如何在Objective-C ++类（.mm）中实现它？