选择器视图选项填充标签

Posted 2023-02-24

【中文标题】选择器视图选项填充标签

【英文标题】：Picker View choices populate labels

【发布时间】：2014-10-20 03:26:19

【问题描述】：

我希望我的选择器视图在用户选择某些选项时填充标签。 示例：组件 1 选项将显示在标签 1 中，组件 2 选项将显示在标签 2 中，组件 3 选项将显示在标签 3 中。

我对普通的选择器没有问题，但是我的选择器组件会根据前一个组件的选择而变化。

例子：

组件1中的第一选择显示组件2中的数据

组件 1 中的第二个选择显示组件 2 中的不同数据

依次在组件 3 中显示不同的数据

它目前没有按我的意愿运行和运行，我不知道我做错了什么。我认为这是我的“didSelectRow”部分，但不完全确定。

.h

#import <UIKit/UIKit.h>

@interface ViewController : UIViewController<UIPickerViewDataSource, UIPickerViewDelegate>

@property (weak, nonatomic) IBOutlet UIPickerView *picker1;
@property (weak, nonatomic) IBOutlet UILabel *label1;
@property (weak, nonatomic) IBOutlet UILabel *label2;
@property (weak, nonatomic) IBOutlet UILabel *label3;

@end

.m

#import "ViewController.h"

@interface ViewController ()

    NSArray*overalltype;
    NSArray*healthtype;
    NSArray*midwifetype;
    NSArray*doctortype;
    NSArray*otherhealthtype;
    NSArray*visitorstype;
    NSArray*othertype;
    NSArray*onlinetype;
    NSArray*volunteertype;

    NSInteger selectedOptionFromColumn1;
    NSInteger selectedOptionFromColumn2;


@end

@implementation ViewController

- (void)viewDidLoad 
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.

    overalltype =[[NSArray alloc]initWithObjects:@"Health Professional", @"HouseKeeping",@"Visitors", @"Other",nil];
    healthtype =[[NSArray alloc]initWithObjects:@"Midwife", @"Nurse",@"Doctor", @"Other Health Professional" ,nil];
    midwifetype =[[NSArray alloc]initWithObjects:@"Known Midwife", @"New Midwife", nil];
    doctortype =[[NSArray alloc]initWithObjects:@"Snr Dr", @"Jnr Dr", @"Baby Dr", @"GP", nil];
    otherhealthtype =[[NSArray alloc]initWithObjects:@"Lactation Consultant", @"Student", @"Hearing Technician", @"Bloody Collector", @"Social Worker", @"Mental Health", @"Physiotherapist", nil];
    visitorstype =[[NSArray alloc]initWithObjects:@"Partner", @"Relatives", @"Friends", @"Other Woman's Visitors", nil];
    othertype =[[NSArray alloc]initWithObjects:@"Online Support", @"Volunteer", @"Church Group", @"Wardsperson", nil];
    onlinetype =[[NSArray alloc]initWithObjects:@"Chatroom", @"Internet Search", nil];
    volunteertype =[[NSArray alloc]initWithObjects:@"ABA", @"Hospital Volunteer", @"Church Group", nil];


-(NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView

    return 3;


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

    switch (component) 
        case 0:
            return overalltype.count;
            break;

        case 1:
            if (selectedOptionFromColumn1 == 0) 
                return healthtype.count;
            
            else if (selectedOptionFromColumn1 == 2)
                return visitorstype.count;
            
            else if (selectedOptionFromColumn1 == 3)
                return othertype.count;
            
            break;

        case 2:
            if (selectedOptionFromColumn1 == 0 && selectedOptionFromColumn2 ==0) 
                return midwifetype.count;
            
            else if (selectedOptionFromColumn1 == 0 && selectedOptionFromColumn2 ==2) 
                return doctortype.count;
            
            else if (selectedOptionFromColumn1 == 0 && selectedOptionFromColumn2 ==3) 
                return otherhealthtype.count;
            
            else if (selectedOptionFromColumn1 == 3 && selectedOptionFromColumn2 ==0) 
                return onlinetype.count;
            
            else if (selectedOptionFromColumn1 == 3 && selectedOptionFromColumn2 ==1) 
                return volunteertype.count;
            
            break;

        default:
            break;
    
    return 0;


-(NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component 
    switch (component) 
        case 0:
            return [overalltype objectAtIndex:row];
            break;

        case 1:
            if (selectedOptionFromColumn1 == 0) 
                return [healthtype objectAtIndex:row];
            
            else if (selectedOptionFromColumn1 == 2) 
                return [visitorstype objectAtIndex:row];
            
            else if (selectedOptionFromColumn1 ==3)
                return [othertype objectAtIndex:row];
            
            break;

    case 2:
            if (selectedOptionFromColumn1 == 0 && selectedOptionFromColumn2 == 0) 
                return [midwifetype objectAtIndex:row];
            
            else if (selectedOptionFromColumn1 == 0 && selectedOptionFromColumn2 == 2) 
                return [doctortype objectAtIndex:row];
            
            else if (selectedOptionFromColumn1 == 0 && selectedOptionFromColumn2 == 3) 
                return [otherhealthtype objectAtIndex:row];
            
            else if (selectedOptionFromColumn1 == 3 && selectedOptionFromColumn2 == 0) 
                return [onlinetype objectAtIndex:row];
            

            else if (selectedOptionFromColumn1 == 3 && selectedOptionFromColumn2 == 1) 
                return [volunteertype objectAtIndex:row];
            
            break;

        default:
            break;
    
    return 0;


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

    switch (component) 

        case 0:
            selectedOptionFromColumn1=[pickerView selectedRowInComponent:0];
            [pickerView reloadComponent:1];
            _label1.text = [overalltype objectAtIndex: [pickerView selectedRowInComponent:0]];

        case 2:
            selectedOptionFromColumn2=[pickerView selectedRowInComponent:1];
            [pickerView reloadComponent:2];
            if(selectedOptionFromColumn1 == 0)
                _label2.text = [healthtype objectAtIndex: [pickerView selectedRowInComponent:1]];
            

            else if(selectedOptionFromColumn1 ==2)
                _label2.text = [visitorstype objectAtIndex: [pickerView selectedRowInComponent:1]];
            
            else if(selectedOptionFromColumn1 ==3)
                _label2.text = [otherhealthtype objectAtIndex: [pickerView selectedRowInComponent:1]];
            

        case 3:
            if (selectedOptionFromColumn1 ==0 && selectedOptionFromColumn2 == 0)
            _label3.text = [midwifetype objectAtIndex: [pickerView selectedRowInComponent:2]];
            
            else if(selectedOptionFromColumn1 ==0 && selectedOptionFromColumn2 ==2)
            _label3.text = [doctortype objectAtIndex: [pickerView selectedRowInComponent:2]];
            
            else if(selectedOptionFromColumn1 ==0 && selectedOptionFromColumn2 == 3)
                _label3.text = [otherhealthtype objectAtIndex: [pickerView selectedRowInComponent:2]];
            

            else if(selectedOptionFromColumn1 ==3 && selectedOptionFromColumn2 == 0)
                _label3.text = [onlinetype objectAtIndex: [pickerView selectedRowInComponent:2]];
            
            else if(selectedOptionFromColumn1 ==3 && selectedOptionFromColumn2 == 1)
                _label3.text = [volunteertype objectAtIndex: [pickerView selectedRowInComponent:2]];
            
    


- (void)didReceiveMemoryWarning [super didReceiveMemoryWarning];


@end

【问题讨论】：

什么错误？您需要提供更多详细信息以供任何人提供帮助。

另外，为了将来，尝试将您的代码格式化为尽可能可读。这次给你做了，你看一下，对我们理解你的问题很有帮助。

【参考方案1】：

您在 didSelectRow 方法中缺少 break 语句作为每个 case 语句的一部分。

您可能还想考虑使用 Modern Objective-C，https://developer.apple.com/library/ios/releasenotes/ObjectiveC/ModernizationObjC/AdoptingModernObjective-C/AdoptingModernObjective-C.html，它更容易阅读