用UIPicker做一个类似省市联动选择的例子

ViewController.h:

#import <UIKit/UIKit.h>

@interface ForthViewController :UIViewController<UIPickerViewDataSource,UIPickerViewDelegate>

@property (retain,nonatomic) IBOutlet UIPickerView *picker;

@property(nonatomic,retain)NSDictionary *dictionary;

@property(nonatomic,retain)NSArray *states;  //省

@property(nonatomic,retain)NSArray *zips;//市

@end

ViewController.m:

#import"ForthViewController.h"

#define STATE_COMPONENT0

#define ZIP_COMPONENT 1

@interfaceForthViewController ()

@end

@implementation ForthViewController

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil

{

    self = [superinitWithNibName:nibNameOrNil bundle:nibBundleOrNil];

    if (self) {

       // Custom initialization

    }

    return self;

}

- (void)viewDidLoad

{

    [superviewDidLoad];

    NSBundle *bundle = [NSBundle mainBundle];//目录，地址

    NSURL * url = [bundle URLForResource:@"statedictionary"withExtension:@"plist"];

    NSString *path = [bundle pathForResource:@"statedictionary"ofType:@"plist"];

    NSLog(@"%@",url);

    NSLog(@"%@",path);

    NSDictionary *dic = [NSDictionary dictionaryWithContentsOfFile:path];

    self.dictionary = dic;

    NSLog(@"%@",self.dictionary);

    NSArray *arr = [self.dictionaryallKeys];

    self.states = arr;

    arr= [self.dictionaryobjectForKey:self.states[0]];

    self.zips = arr;

}

- (void)didReceiveMemoryWarning

{

    [superdidReceiveMemoryWarning];

    // Dispose of any resources that can be recreated.

}

//一个picker有几个compont

-(NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView

{

    return2;

}

//每个组件有几行数据

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

{

    //创建数据

    if(component ==STATE_COMPONENT)

    {

        return [self.states count];   //动态获取数字

    }

    else

    {

        return [self.zips count];

    }

}

//每行显示的内容

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

{

    if (component ==STATE_COMPONENT) {

        return [self.states objectAtIndex:row];

    }

    else

    {

        return [self.zips objectAtIndex:row];

    }

}

//选择一行就触发的事件

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

{

    if (component ==STATE_COMPONENT) {

        NSString *str = [self.statesobjectAtIndex:row];

        NSArray *arr = [self.dictionaryvalueForKey:self.states[row]];

        self.zips = arr;

       //因为component = ZIP_COMPONENT的数据发生改变，所以要重新导入

        [pickerView reloadComponent:ZIP_COMPONENT];

       //防止越界，row超过现在的总行数

        [pickerViewselectRow:0inComponent:ZIP_COMPONENTanimated:YES];

    }

}

- (void)dealloc {

    [_pickerrelease];

    [_dictionaryrelease];

    [_statesrelease];

    [_zipsrelease];

    [superdealloc];

}

@end

项目源码：http://download.csdn.net/detail/s10141303/5958499

本文转蓬莱仙羽51CTO博客，原文链接：http://blog.51cto.com/dingxiaowei/1366433，如需转载请自行联系原作者