ios – 使用Swift集成Objective C协议

我是 swift的新手,我需要一些帮助来整合
组件AKPickerView(用Objective C编写).
组件链接： https://github.com/Akkyie/AKPickerView

但我没有成功,因为有一个协议：AKPickerViewDelegate在Swift中不起作用：

@class AKPickerView;

@protocol AKPickerViewDelegate <NSObject>
@optional
- (NSString *)pickerView:(AKPickerView *)pickerView titleForItem:(NSInteger)item;
- (NSUInteger)numberOfItemsInPickerView:(AKPickerView *)pickerView;
- (void)pickerView:(AKPickerView *)pickerView didSELEctItem:(NSInteger)item;
@end

在Swift中我编写了这段代码：

class ViewController: UIViewController,AKPickerViewDelegate {

var pickerView : AKPickerView = AKPickerView()
var titles     : NSArray = ["Janeiro","Fevereiro","Março","Abril","Maio"]

...

我鼓励这种方法：

func numberOfItemsInPickerView(pickerView : AKPickerView!) -> Int{

    return self.titles.count
}


func pickerView(pickerView: AKPickerView,titleForItem item : NSInteger) -> NSString {

    return self.titles[item] as NSString
}

但编译器显示此错误：

Type 'ViewController' does not conform to protocol 'AKPickerViewDelegate'

感谢一些帮助
谢谢！

@protocol AKPickerViewDelegate <NSObject>
@required
- (NSUInteger)numberOfItemsInPickerView:(AKPickerView *)pickerView;
- (NSString *)pickerView:(AKPickerView *)pickerView titleForItem:(NSInteger)item;
@optional
- (void)pickerView:(AKPickerView *)pickerView didSELEctItem:(NSInteger)item;
@end

func numberOfItemsInPickerView(pickerView: AKPickerView!) -> UInt {

    return self.titles.count
}

func pickerView(pickerView: AKPickerView!,titleForItem item: int) -> String! {

   return self.titles[item]
}