IOS的UIPickerView 和UIDatePicker

1.UIPickerView的常见属性

 //数据源(用来告诉UIPickerView有多少列多少行)
 @property(nonatomic,assign) id<UIPikerViewDataSource> dataSource;
 //代理(用来告诉UIPickerView每一列的每一行显示什么内容,监听UIPickerView的选择)
 @property(nonatomic,assign) id<UIPickerViewDelegate> delegate;
 //是否要显示选中的指示器
 @property(nonatomic) BOOL  showsSelectionIndicator;
 //一共有多少列
 @property(nonatomic,readonly) NSInteger numberOfComponents;

2.UIPickerView的常见方法

 //重新刷新所有列
 -(void)reloadAllComponents;
 //重新刷新第component列
 -(void)reloadComponent:(NSInteger)component;
 //主动选中第component列的第row行
 -(void)selectRow:(NSInteger)row inComponent:(NSInteger)component animated:(BOOL) animated;
 //获取第component列的当前选中的行号
 -(NSInteger)selectedRowIncomponent:(NSInteger) component;

3.数据源方法(UIPickerViewDataSource)

//  一共有多少列
- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView;
//  第component列一共有多少行
- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component;

4.代理方法(UIPickerViewDelegate)

 //  第component列的宽度是多少
 - (CGFloat)pickerView:(UIPickerView *)pickerView widthForComponent:(NSInteger)component;
 //  第component列的行高是多少
 - (CGFloat)pickerView:(UIPickerView *)pickerView rowHeightForComponent:(NSInteger)component;

 //  第component列第row行显示什么文字
 - (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component;

 //  第component列第row行显示怎样的view(内容)
 - (UIView *)pickerView:(UIPickerView *)pickerView viewForRow:(NSInteger)row forComponent:(NSInteger)component reusingView:(UIView *)view;

 //  选中了pickerView的第component列第row行
 - (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component;

UIDatePicker

1.常见属性

 // datePicker的显示模式
 @property (nonatomic) UIDatePickerMode datePickerMode;
 // 显示的区域语言
 @property (nonatomic, retain) NSLocale   *locale;

2.监听UIDatePicker的选择

因为UIDatePicker继承自UIControl,所以通过addTarget:..监听