picker VIew初始化和加载plist数据

实现PickerView的数据初始化

//确定pickerVIew轮子的个数
-(NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView
{
    return 2;
}
//确定pickerView的每个轮子的item数
-(NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component
{
    if (component == 0) {//省份个数
        return [provinceArray count];
    }
    else  //市的个数
    {
        return [cityArray count];
    }
}
//确定每个轮子的每一项显示什么内容
#pragma mark 实现协议UIPickerViewDelegate方法
-(NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component
{
    if (component == 0) {//选择省份名
        return [provinceArray objectAtIndex:row];
    }
    else//选择市名
    {
        return [cityArray objectAtIndex:row];
    }
}

//加载数据plist里面的数据
NSString *plistPath = [[NSBundle mainBundle]pathForResource:@"province" ofType:@"plist"];
//获取属性列表文件中的全部数据
NSDictionary *dict = [[NSDictionary alloc]initWithContentsOfFile:plistPath];
self.pickerData = dict;

//省份名数据
self.pickerProvincesData = [self.pickerData allKeys];

//默认取出第一个省的所有市的数据
NSString *seletedProvince = [self.pickerProvincesData objectAtIndex:0];
self.pickerCitiesData = [self.pickerData objectForKey:seletedProvince];

self.pickerView.dataSource = self;
self.pickerView.delegate = self;