UIPickerView 常用方法

1.//返回每个组件上的行数

-(NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component

2.//返回组件数

-(NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView

3.//每一列中每一行的具体内容

- (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component;

4.//返回组件的高度，如果这个方法未实现，选取器会自动调整到合适的高度

-(CGFloat)pickerView:(UIPickerView *)pickerView rowHeightForComponent:(NSInteger)component

5.//选中哪一列哪一行

-(void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component;

6.获得选取器视图被选中列的索引：

int selectedRow = [_pickerView selectedRowInComponent:0];

7.设置选取器初始选中行：

[pickerview selectRow:0 inComponent:0 animated:YES];