我怎样才能将默认实现didSet设置为protocol var
我试试,但我有错误
我试试,但我有错误
Extensions may not contain stored properties
protocol MyProtocol {
var contact: MyContact? { get set }
}
extension MyProtocol {
var contact: MyContact? {
didSet {
// some code
}
}
}
解决方法
来自文档：
Extensions can add new computed properties,but they cannot add stored properties,or add property observers to existing properties.
如果要设置联系人的默认值,则必须是计算属性.
extension MyProtocol {
var contact: MyContact? {
return MyContact()
}
}