英文:
Swift: Computed Property - call function when value changed
问题
我需要一个变量来保留对对象数组的选定索引。
每当此索引更改时，我需要进行函数调用。
我曾认为计算属性是解决方法，但我遇到了递归问题。
var selectedIndex: Int = 0
{
get
{
return self.selectedIndex
}
set
{
self.selectedIndex = newValue
self.delegate?.updatedValue()
}
}
我该如何修复这个问题？
英文:
I have need of a variable that retains the selected index into an array of objects.
I need to make a function call whenever this index changes.
I had thought that computed properties were the way to go but I'm having problems with recursion
var selectedIndex : Int = 0
{
get
{
return self.selectedIndex
}
set
{
self.selectedIndex = newValue
self.delegate?.updatedValue()
}
}
How can I fix this?
答案1
得分: 2
只需要为存储属性添加一个 didSet。
var selectedIndex : Int = 0 {
didSet {
self.delegate?.updatedValue()
}
}
英文:
You just need to add a didSet to the stored property.
var selectedIndex : Int = 0 {
didSet {
self.delegate?.updatedValue()
}
}
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