2017-02-14 163 views
1

使用MapKit的CLGeocoder()。geocodeAddressString()来获取地址列表的坐标和县信息。只要请求数低于50,一切都可以工作,但超过50就会超出API的限制。由于CLGeocoder调用是异步的,因此我无法轻松地调节/控制调用流(例如,一次调用一个地址)。我如何在“异步世界”中正确执行此操作? (免责声明:我是新来的GCD和异步流量控制的世界,所以我想我可能需要更详细的回应)CLGeocoder geocodeAddressString()达到极限

下面是相关代码:

类属性的方法是在调用CLGeocoder物业公司地址:

func initializeCoordinates() { 

     let addressForCoords = self.address.getAddress() 
     CLGeocoder().geocodeAddressString(addressForCoords, completionHandler: { (placemarks, error) -> Void in 
      if error != nil { 
       print(error!) 
       return 
      } 
      if placemarks!.count > 0 { 
       let placemark = placemarks?[0] 
       let location = placemark?.location 
       self.coordinates = location?.coordinate 

       if let subAdminArea = placemark?.subAdministrativeArea { 
        self.address.county = subAdminArea 
       } 
      } 
     }) 
    } 

,然后在导入所有属性的地址从一个文本框(并使得调用initializeCoordinates方法对每个属性ImportVC部分:

for line in importText { 
     let newAddress = Address() 
     let newHouse = Property() 

     // parse the tab delimited address for each line of input 
     let address = line.components(separatedBy: "\t") 
     if address.count == 4 { 
      newAddress.street = address[0] 
      newAddress.city = address[1] 
      newAddress.state = trimState(state: address[2]) 
      newAddress.zip = address[3] 
      newHouse.address = newAddress 
      newHouse.initializeCoordinates() 
      houses.append(newHouse) 
     } 
    } 

回答

0

我最近遇到了类似的问题。用最后调用自己的递归函数替换你的for循环。然而,诀窍是以0.2秒的延迟来调用自己。我使用0.4来保证安全。这将增加用户的等待时间,但由于API限制,我们没有选择。