UIPickerView行数

Question

如何获取UIPickerView中的项目数（行数）？我似乎找不到能告诉我这个的财产。

Answer 1

来自UIPicker documentation

@property（nonatomic，readonly）NSInteger numberOfComponents

• （NSInteger的）numberOfRowsInComponent：（NSInteger的）组件;

Answer 2

构建一个新的PickerViewHelper文件。为UIPickerViewDataSource委托实现此必需的方法。

@interface PickerViewHelper : UIViewController<UIPickerViewDelegate, UIPickerViewDataSource>
// returns the # of rows in each component..
- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component;

然后在UIViewController，获取数字：

long number = [self.yourPicker numberOfRowsInComponent : 0 ];