iOS国家城市选择器 读取本地json文件

最近在做的产品有这么个需求，读取本地json文件中的国家和城市信息，显示到pickerview上，在网上查了一下，发现没有什么合适的可用资源，所以就自己写了一个简单的DEMO。

效果图：

读取本地json的方法如下：

+ (NSMutableArray *)getCityData{    NSArray *jsonArray = [[NSArray alloc]init];    NSData *fileData = [[NSData alloc]init];    NSUserDefaults *UD = [NSUserDefaults standardUserDefaults];    if ([UD objectForKey:@"city"] == nil) {        NSString *path;        path = [[NSBundle mainBundle] pathForResource:@"zh_CN" ofType:@"json"];        fileData = [NSData dataWithContentsOfFile:path];                [UD setObject:fileData forKey:@"city"];        [UD synchronize];    }    else {        fileData = [UD objectForKey:@"city"];    }    NSMutableArray *array = [[NSMutableArray alloc]initWithCapacity:0];    jsonArray = [NSJSONSerialization JSONObjectWithData:fileData options:NSJSONReadingMutableLeaves error:nil];    for (NSDictionary *dict in jsonArray) {        [array addObject:dict];    }        return array;}

citypicker主要代码如下：

//返回显示的列数- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView{    if (pickerView == self.cityPicker) {        return 3;    }    else        return 1;}//返回当前列显示的行数- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component{        if (component == 0) {        return [YMUtils getCityData].count;    }    else if (component == 1) {        NSArray *array = [YMUtils getCityData][row1][@"children"];        if ((NSNull*)array != [NSNull null]) {            return array.count;        }        return 0;    }    else {        NSArray *array = [YMUtils getCityData][row1][@"children"];        if ((NSNull*)array != [NSNull null]) {            NSArray *array1 = [YMUtils getCityData][row1][@"children"][row2][@"children"];            if ((NSNull*)array1 != [NSNull null]) {                return array1.count;            }            return 0;        }        return 0;    }}//设置当前行的内容- (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component{        if(component == 0) {        return [YMUtils getCityData][row][@"name"];    }    else if (component == 1) {        return [YMUtils getCityData][row1][@"children"][row][@"name"];    }    else if (component == 3) {        return [YMUtils getCityData][row1][@"children"][row2][@"children"][row][@"name"];    }    return nil;    }//选择的行数- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component {    if (component == 0) {        row1 = row;        row2 = 0;        row3 = 0;        [self.cityPicker reloadComponent:1];        [self.cityPicker reloadComponent:2];            }    else if (component == 1){        row2 = row;        row3 = 0;        [self.cityPicker reloadComponent:2];            }    else {        row3 = row;    }    NSInteger cityRow1 = [self.cityPicker selectedRowInComponent:0];    NSInteger cityRow2 = [self.cityPicker selectedRowInComponent:1];    NSInteger cityRow3 = [self.cityPicker selectedRowInComponent:2];    NSMutableString *str = [[NSMutableString alloc]init];    [str appendString:[YMUtils getCityData][cityRow1][@"name"]];    NSArray *array = [YMUtils getCityData][cityRow1][@"children"];    if ((NSNull*)array != [NSNull null]) {        [str appendString:[YMUtils getCityData][cityRow1][@"children"][cityRow2][@"name"]];        NSArray *array1 = [YMUtils getCityData][cityRow1][@"children"][cityRow2][@"children"];        if ((NSNull*)array1 != [NSNull null]) {            [str appendString:[YMUtils getCityData][cityRow1][@"children"][cityRow2][@"children"][cityRow3][@"name"]];        }    }    self.cityLabel.text = str;}//每行显示的文字样式- (UIView *)pickerView:(UIPickerView *)pickerView viewForRow:(NSInteger)row forComponent:(NSInteger)component reusingView:(UIView *)view{        UILabel *titleLabel = [[UILabel alloc] initWithFrame:CGRectMake(0, 0, 107, 30)];    titleLabel.textAlignment = NSTextAlignmentCenter;    titleLabel.font = [UIFont systemFontOfSize:14];    titleLabel.backgroundColor = [UIColor clearColor];    if (component == 0) {        titleLabel.text = [YMUtils getCityData][row][@"name"];    }    else if (component == 1) {        titleLabel.text = [YMUtils getCityData][row1][@"children"][row][@"name"];    }    else {        titleLabel.text = [YMUtils getCityData][row1][@"children"][row2][@"children"][row][@"name"];    }    return titleLabel;    }

DEMO的下载地址：http://download.csdn.net/detail/u011918080/8200985