2
我不明白为什么我的scopeButtonTitles总是为零。我遵循RayWenderlich的教程，但不同之处在于我的搜索栏中的元素数组应该从数据库加载的范围按钮标题。scopeButtonTitles总是零
但我仔细检查，我的数组装满了，而不是零。 scopeButtonTitles何时设置？也许这是在我的数组被初始化之前？
这里是我的代码：
var bottlesArray: Array<Bottle>!
override func viewDidLoad() {
super.viewDidLoad()
loadBottles() // loads elements from a DB and initialise bottlesArray
}
func filterContentForSearchText(searchText: String, scope: String = "All") {
// Filter the array using the filter method
self.filteredBottles = self.bottlesArray.filter({(bottle: Bottle) -> Bool in
var categoryMatch = (scope == "All") || (bottle.category == scope)
// The two following line put the search string AND the matching string in Lower case and accent tolerent so, for example "Dôle" == "dole" -> true
var lowerCaseNoAccentTitle: String = NSString(data: bottle.title.lowercaseString.dataUsingEncoding(NSASCIIStringEncoding, allowLossyConversion: true)!, encoding: NSUTF8StringEncoding)!
var lowerCaseNoAccentSearchText: String = NSString(data: searchText.lowercaseString.dataUsingEncoding(NSASCIIStringEncoding, allowLossyConversion: true)!, encoding: NSUTF8StringEncoding)!
var stringMatch = lowerCaseNoAccentTitle.rangeOfString(lowerCaseNoAccentSearchText)
return categoryMatch && (stringMatch != nil)
})
}
func searchDisplayController(controller: UISearchDisplayController!, shouldReloadTableForSearchString searchString: String!) -> Bool {
let scopes = self.searchDisplayController!.searchBar.scopeButtonTitles as [String]
let selectedScope = scopes[self.searchDisplayController!.searchBar.selectedScopeButtonIndex] as String
self.filterContentForSearchText(searchString, scope: selectedScope)
return true
}
func searchDisplayController(controller: UISearchDisplayController!,
shouldReloadTableForSearchScope searchOption: Int) -> Bool {
let scope = self.searchDisplayController!.searchBar.scopeButtonTitles as [String]
self.filterContentForSearchText(self.searchDisplayController!.searchBar.text, scope: scope[searchOption])
return true
}
因此，要明确，self.searchDisplayController!.searchBar不是零，但scopeButtonTitles是。如果我手动设置self.searchDisplayController!.searchBar.scopeButtonTitles那么范围栏工作。但在教程中它会自动加载。
我不明白什么时候scopeButtonTitles阵列应该被填充。
这正是你应该问教程的原作者的问题。 –