ios7 uipickerview

@interface  () <UIPickerViewDataSource, UIPickerViewDelegate>

@property (nonatomic, strong) UIPickerView *myPicker;
@end

- (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component{
    if ([pickerView isEqual:self.myPicker]){
        //返回 row index，默认为0+1
        return [NSString stringWithFormat:@"Row %ld", (long)row + 1];
    }
    return nil;
    
}

- (void)viewDidLoad{
    [super viewDidLoad];
	//创建UIPickerView
    self.myPicker = [[UIPickerView alloc] init];
    //是否选择显示指示器
    self.myPicker.showsSelectionIndicator = NO;
    //数据&协议
    self.myPicker.dataSource = self;
    self.myPicker.delegate = self;
    //居中
    self.myPicker.center = self.view.center;
    //添加到view
    [self.view addSubview:self.myPicker];
    
}

//返回列的显示数量
- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView{
    
    if ([pickerView isEqual:self.myPicker]){
        return 1;
    }
    return 0;

}

//返回row数
- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component{
    
    if ([pickerView isEqual:self.myPicker]){
        return 10;
    }
    return 0;

}