一个简单的plist 解析过程，借助UIPickerView 实现了手选全国的 省市区 方法，
源码中有详细注释；长句自己可以拆开看，最好的方法是，拆开，并打印，查看每一步打印的结果，结合Plist文件，解读文件读取过程
基本原理是通过字典 、数组、逐层剥壳
源码：
.h
//
// ViewController.h
// AreaAnalysis
//
// Created by Ibokan on 15/8/28.
// Copyright (c) 2015年 Crazy凡. All rights reserved.
// #import <UIKit/UIKit.h> @interface ViewController : UIViewController <UIPickerViewDelegate, UIPickerViewDataSource>//遵守协议 @end
.m
//
// ViewController.m
// AreaAnalysis
//
// Created by Ibokan on 15/8/28.
// Copyright (c) 2015年 Crazy凡. All rights reserved.
// #import "ViewController.h" @interface ViewController ()
@property (weak, nonatomic) IBOutlet UIPickerView *pickerView;
@property (weak, nonatomic) IBOutlet UILabel *infoLabel;
@property (nonatomic,strong) NSArray *province;
@property (nonatomic,strong) NSMutableArray *tempdata;//装载当前省的全部数据
@property (nonatomic, strong) NSMutableArray *pickerProvincesData;//当所有省的名称数据
@property (nonatomic, strong) NSMutableArray *pickerCitiesData;//当前的省下面的市名称数据
@property (nonatomic, strong) NSMutableArray *pickerDistrictData;//当前的市下面的区的名称数据
@property int ia,ib;
@end
@implementation ViewController - (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view.
self.province = [[NSArray alloc]initWithContentsOfFile:[[NSBundle mainBundle] pathForResource:@"area2.plist" ofType:nil]];
self.pickerProvincesData = [[NSMutableArray alloc]init];
self.pickerCitiesData = [[NSMutableArray alloc]init];
self.pickerDistrictData = [[NSMutableArray alloc]init];
self.tempdata = [[NSMutableArray alloc]init];
for(int i = ; i < self.province.count ; [self.pickerProvincesData addObjectsFromArray:[self.province[i++] allKeys]]);//取出所有的keys（省）仅有名称，数据部分是根据省动态获取的
self.ia = self.ib = ;
[self getPickerCitiesData];//获取初始化市
[self getPickerDistrictData];//获取初始化区
self.pickerView.dataSource = self;
self.pickerView.delegate = self;
[self.infoLabel setText:[NSString stringWithFormat:@"%@;%@;%@",self.pickerProvincesData[[self.pickerView selectedRowInComponent:]],self.pickerCitiesData[[self.pickerView selectedRowInComponent:]],self.pickerDistrictData[[self.pickerView selectedRowInComponent:]]]];//让label 显示选中的内容（初始化后显示）
}
- (void)getPickerCitiesData//装载市
{
[self.pickerCitiesData removeAllObjects];//清除数据
[self.tempdata removeAllObjects];//清除数据
[self.tempdata addObjectsFromArray:[[NSArray alloc]initWithArray:[self.province[self.ia] valueForKey:self.pickerProvincesData[self.ia]]]];//将当前省的所有数据保存在一个数组中，避免反复读取
for(NSDictionary *dir in self.tempdata) { [self.pickerCitiesData addObjectsFromArray:[dir allKeys]]; }//将市的名称取出
}
- (void)getPickerDistrictData//装载区
{
[self.pickerDistrictData removeAllObjects];
[self.pickerDistrictData addObjectsFromArray:[self.tempdata [self.ib]valueForKey:self.pickerCitiesData[self.ib]]];//填充区的名称
}
#pragma mark 实现协议UIPickerViewDataSource方法
- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView {return ; }//设定有几列
- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component {
switch (component) {//设定每一列有多少行
case : return self.pickerProvincesData.count; break;
case : return self.pickerCitiesData.count; break;
case : return self.pickerDistrictData.count; break;
default: break;
}
return ;
}
#pragma mark 实现协议UIPickerViewDelegate方法
-(NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component {//设定行内容
switch (component) {
case : return [self.pickerProvincesData objectAtIndex:row]; break;
case : return [self.pickerCitiesData objectAtIndex:row]; break;
case : return [self.pickerDistrictData objectAtIndex:row]; break;
default: break;
}
return ;
}//设定行内容结束
- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component {
switch (component) {//检测滑动事件（row 是行 component 是代表滚动的列）
case :
self.ia = (int) row;
self.ib = ;
[self getPickerCitiesData];//重新装载城市数据
[self getPickerDistrictData];//重新装载区数据
[self.pickerView reloadComponent:];//重新填充城市列表
[self.pickerView reloadComponent:];//重新填充城市列表
break;
case :
self.ib = (int) row;
[self getPickerDistrictData];
[self.pickerView reloadComponent:];
break;
default: break;
}
[self.infoLabel setText:[NSString stringWithFormat:@"%@;%@;%@",self.pickerProvincesData[[self.pickerView selectedRowInComponent:]],self.pickerCitiesData[[self.pickerView selectedRowInComponent:]],self.pickerDistrictData[[self.pickerView selectedRowInComponent:]]]];//刷新 label 显示的内容 （每次滚动后刷新）
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
@end
知识点：
先说一下 UIPickerView吧，我只是让你会用，理解的话，自己看文档 command + 鼠标左键 别告诉我不认识英文，我也不认识！
废话不多说：
首先是遵守协议：
<UIPickerViewDelegate, UIPickerViewDataSource>//遵守协议
其次 是实现方法；也就是下面很长这一块；代码中有注释，我再摘出来单独说一下
#pragma mark 实现协议UIPickerViewDataSource方法
- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView {return 3; }//设定有几列（return N 就有N列）
- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component {
switch (component) {//设定每一列有多少行 看参数 component 代表当前在为第几列设定行数，return N 就会为第几列设定多少行
case 0: return self.pickerProvincesData.count; break;
case 1: return self.pickerCitiesData.count; break;
case 2: return self.pickerDistrictData.count; break;
default: break;
}
return 0;
}
#pragma mark 实现协议UIPickerViewDelegate方法
-(NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component {//设定行内容
switch (component) {//设定行的内容，Component 是列 row 是列中的行， 也就是 给 第几行几列设定值（返回值就是 设定的值）
case 0: return [self.pickerProvincesData objectAtIndex:row]; break;
case 1: return [self.pickerCitiesData objectAtIndex:row]; break;
case 2: return [self.pickerDistrictData objectAtIndex:row]; break;
default: break;
}
return 0;//这里是写代码的失误吧，换成nil 更好 为了保证和上面贴的源码一致，就不改了，下面下载的文件中改过来，大家见谅，
}
- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component {
switch (component) {//检测滑动事件（row 是行 component 是代表滚动的列） 判断滑动的是第几列 然后 刷新数据
case 0:
self.ia = (int) row;
self.ib = 0;
[self getPickerCitiesData];//重新装载城市数据
[self getPickerDistrictData];//重新装载区数据
[self.pickerView reloadComponent:1];//重新填充城市列表
[self.pickerView reloadComponent:2];//重新填充城市列表
break;
case 1:
self.ib = (int) row;
[self getPickerDistrictData];
[self.pickerView reloadComponent:2];
break;
default: break;
}
[self.infoLabel setText:[NSString stringWithFormat:@"%@;%@;%@",self.pickerProvincesData[[self.pickerView selectedRowInComponent:0]],self.pickerCitiesData[[self.pickerView selectedRowInComponent:1]],self.pickerDistrictData[[self.pickerView selectedRowInComponent:2]]]];//刷新 label 显示的内容 （每次滚动后刷新）这句下面有解析，我就不重复了
}
1、
self.province = [[NSArray alloc]initWithContentsOfFile:[[NSBundle mainBundle] pathForResource:@"area2.plist" ofType:nil]];
不多解释，Plist文件读取，很多次了，
2、
self.pickerProvincesData = [[NSMutableArray alloc]init];
可变数组初始化，记得使用之前一定要初始化，一定要初始化，一定要初始化，重要的事情说三遍！！很小的问题，但是（自己）会经常忘掉，然后找半天错……都是空、都是泪、
3、
for(int i = 0 ; i < self.province.count ; [self.pickerProvincesData addObjectsFromArray:[self.province[i++] allKeys]]);
字典数组怎么取出所有字典的key值，addObjectsFromArray 和 allKeys 的完美搭配
4、
[self.pickerCitiesData removeAllObjects];//清除数据
重新使用可变数组记得清空！！！
5、
[self.infoLabel setText:[NSString stringWithFormat:@"%@;%@;%@",self.pickerProvincesData[[self.pickerView selectedRowInComponent:0]],self.pickerCitiesData[[self.pickerView selectedRowInComponent:1]],self.pickerDistrictData[[self.pickerView selectedRowInComponent:2]]]];
好吧，这句话好长，但是很简单
可以拆为stringWithFormat 和 self.pickerView selectedRowInComponent:0 前一句 应该都懂了，后面一句是取出当前选中的是第几行