省市区选择器

     省市区选择器显示一般通过PickerView 和 TableView来实现，数据通过plist属性文件，sqlite，或是文本文件实现。

我的这个是通过txt文本本件实现的。

　　首先对txt文件进行解析，把解析的数据放到数组中。

　　然后，用通过pickerView或tableView控件显示就ok了。

  PickerView实现的效果：

  TableView实现的效果：

核心代码：

#import "ProvinceViewController.h"
#import "CityViewController.h"

@interface ProvinceViewController ()

@end

@implementation ProvinceViewController

- (void)loadData{
    NSString *filePath = [[NSBundle mainBundle] pathForResource:@"area" ofType:@"txt"];
    NSString *areaString = [NSString stringWithContentsOfFile:filePath
                                                     encoding:NSUTF8StringEncoding
                                                        error:nil];
    NSArray *areasArray = [areaString componentsSeparatedByString:@"\n"];
    _aArray = [NSMutableArray array];
    for (NSString *string in areasArray) {
        if (![string hasPrefix:@" "]) {
            NSMutableArray *cities = [NSMutableArray array];
            string = [self cutStringForSuffixBlank:string];
            NSDictionary *province = [NSDictionary dictionaryWithObjectsAndKeys:string,@"pName",cities,@"cities", nil];
            [_aArray addObject:province];
            continue;
        }
        if ([string hasPrefix:@"  "] && ![string hasPrefix:@"   "]) {
            NSDictionary *province = [_aArray lastObject];
            NSMutableArray *cities = [province objectForKey:@"cities"];
            
            NSMutableArray *areas = [NSMutableArray array];
            string = [self cutStringForPrefixBlank:string];
            string = [self cutStringForSuffixBlank:string];
            NSDictionary *city = [NSDictionary dictionaryWithObjectsAndKeys:string,@"cName",areas,@"areas", nil];
            [cities addObject:city];
            continue;
        }
        NSDictionary *city = [[[_aArray lastObject] objectForKey:@"cities"] lastObject];
        NSMutableArray *areas = [city objectForKey:@"areas"];
        string = [self cutStringForPrefixBlank:string];
        string = [self cutStringForSuffixBlank:string];
        [areas addObject:string];
    }
     _areaData = [[AreaData alloc] initWithDataArray:_aArray];
}

- (NSString *)cutStringForPrefixBlank:(NSString *)string{
    for (int i = 0; i < 5; i++) {
        if ([string hasPrefix:@" "]) {
            string = [string substringFromIndex:1];
        }
    }
    return string;
}

- (NSString *)cutStringForSuffixBlank:(NSString *)string{
    int index = 0;
    for (int i = 0; i < [string length]; i++) {
        unichar c = [string characterAtIndex:i];
        if (c == ' ') {
            NSLog(@"%d",i);
            index = i;
        }
    }
    NSString *stringResult = [string substringToIndex:index];
    return stringResult;
}

- (void)createControl{

    CGRect rect = CGRectZero;
    rect.size.width = self.view.bounds.size.width;
    rect.size.height = self.view.bounds.size.height - 44.0;
    
    UITableView *tableView = [[UITableView alloc] initWithFrame:rect];
    [tableView setDataSource:self];
    [tableView setDelegate:self];
    [self.view addSubview:tableView];
}

- (void)viewDidLoad
{
    [super viewDidLoad];
    [self loadData];
    [self createControl];
}

- (void)dealloc{

    [_areaData release];
    [super dealloc];
}

# pragma mark -- UITableViewDataSource
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section{
    
    return [_areaData provinces];
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{
    static NSString *cellIdentifier = @"cell";
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:cellIdentifier];
    if (!cell) {
        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cellIdentifier];
    }
    [cell setAccessoryType:UITableViewCellAccessoryDetailDisclosureButton];
    [cell.textLabel setText:[_areaData province:indexPath.row]];
    return cell;
}

# pragma mark -- UITableViewDelegate

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath{

    CityViewController *city = [[[CityViewController alloc] init] autorelease];
    [city setTitle:@"市"];
    [city setAreaData:_areaData];
    [city setIndexForProvince:indexPath.row];
    [self.navigationController pushViewController:city animated:YES];
}

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

@end