PickerView。如何在第一个动作中移动到第二个组件

Question

我有UIPickerView有两个组件。我想要第一个组件的动作和第二个自动移动。

不要提供- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component

Answer 1

//  WPSecondViewController.h
//  test
//
//  Created by VASANTH K on 21/01/14.
//

#import <UIKit/UIKit.h>

@interface WPSecondViewController : UIViewController<UIPickerViewDataSource,UIPickerViewDelegate>

@property (strong, nonatomic) IBOutlet UIPickerView *picker;
@end

不要忘记将选择器的delegate和datasource设置为viewController。

//
//  WPSecondViewController.m
//  test
//
//  Created by VASANTH K on 21/01/14.
//

#import "WPSecondViewController.h"

@interface WPSecondViewController ()

@end

此代码简单滚动一个组件以匹配另一个组件行。

@implementation WPSecondViewController

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {
        // Custom initialization
    }
    return self;
}

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view.
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}


#pragma mark -
#pragma mark PickerView DataSource

- (NSInteger)numberOfComponentsInPickerView:
(UIPickerView *)pickerView
{
    return 2;
}

- (NSInteger)pickerView:(UIPickerView *)pickerView
numberOfRowsInComponent:(NSInteger)component
{
    return 20;
}

- (NSString *)pickerView:(UIPickerView *)pickerView
             titleForRow:(NSInteger)row
            forComponent:(NSInteger)component
{
    return [NSString stringWithFormat:@"%d_%d",row,component];
}

#pragma mark -
#pragma mark PickerView Delegate
-(void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row
      inComponent:(NSInteger)component
{
    if(component==0)
    {
    [self.picker selectRow:row inComponent:1 animated:YES];
    }
    else
    {
        [self.picker selectRow:row inComponent:0 animated:YES];
    }


}

@end