类说明
CAPickerView的滚动事件的代理
CAPickerViewDelegate 方法（点击查看方法介绍）
| 方法 | 说明 |
| numberOfComponentsInPickerView | 获取PickerView的Component数量 |
| numberOfRowsInComponent | 获取PickerView的Component行数 |
| widthForComponent | PickerView的Component宽度 |
| rowHeightForComponent | PickerView的Component高度 |
| titleForRow | PickerView的Row标题 |
| viewForRow | PickerView的背景图像 |
| viewForSelect | PickerView的选中时图像 |
CAPickerViewDelegate 方法说明
virtual unsigned int numberOfComponentsInPickerView(CAPickerView* pickerView) = 0;
返回值：unsigned int
参数：
| 类型 | 参数名 | 说明 |
| CAPickerView* | pickerView | 当前pickerView |
解释：获取PickerView的Component数量
virtual unsigned int numberOfRowsInComponent(CAPickerView* pickerView, unsigned int component) = 0;
返回值：unsigned int
参数：
| 类型 | 参数名 | 说明 |
| CAPickerView* | pickerView | 当前pickerView |
| unsigned int | component | 当前选中的component |
解释：获取PickerView的Component行数
virtual float widthForComponent(CAPickerView* pickerView, unsigned int component) {return 0;}
返回值：float
参数：
| 类型 | 参数名 | 说明 |
| CAPickerView* | pickerView | 当前pickerView |
| unsigned int | component | 当前选中的component |
解释：PickerView的Component宽度
virtual float rowHeightForComponent(CAPickerView* pickerView, unsigned int component) {return 0;}
返回值：float
参数：
| 类型 | 参数名 | 说明 |
| CAPickerView* | pickerView | 当前pickerView |
| unsigned int | component | 当前选中的component |
解释：PickerView的Component高度
virtual const char* titleForRow(CAPickerView* pickerView, unsigned int row, unsigned int component) {return NULL;}
返回值：const char*
参数：
| 类型 | 参数名 | 说明 |
| CAPickerView* | pickerView | 当前pickerView |
| unsigned int | row | 当前选中的row |
| unsigned int | component | 当前选中的component |
解释：PickerView的Row标题
virtual CAView* viewForRow(CAPickerView* pickerView, unsigned int row, unsigned int component) {return NULL;}
返回值：CAView*
参数：
| 类型 | 参数名 | 说明 |
| CAPickerView* | pickerView | 当前pickerView |
| unsigned int | row | 当前选中的row |
| unsigned int | component | 当前选中的component |
解释：PickerView的背景图像
virtual CAView* viewForSelect(CAPickerView* pickerView, unsigned int component, const DSize& size) {return NULL;}
返回值：CAView*
参数：
| 类型 | 参数名 | 说明 |
| CAPickerView* | pickerView | 当前pickerView |
| unsigned int | component | 当前选中的component |
| const DSize& | size | 图像大小 |
解释：PickerView的选中时图像