swift3 - 转换为Swift3错误

Question

Xcode转换为Swift 3.0语法后，出现以下错误:

error: cannot invoke initializer for type 'Int' with an argument list of type '(qos_class_t)' DispatchQueue.global(priority: Int(DispatchQoS.QoSClass.userInitiated.rawValue)).async { ^

note: overloads for 'Int' exist with these partially matching parameter lists: (Int64), (Word), (UInt8), (Int8), (UInt16), (Int16), (UInt32), (Int32), (UInt64), (UInt), (Int), (Float), (Double), (Float80), (String, radix: Int), (CGFloat), (NSNumber) {DispatchQueue.global(priority: Int(DispatchQoS.QoSClass.userInitiated.rawValue)).async {

转换后的语法:

func searchBar(_ searchBar: UISearchBar, textDidChange searchText: String) {

    if searchText == "" {
        self.filteredSymbols = self.symbols
        self.alphabeticSymbolCollection.reloadData()
    } else {
        DispatchQueue.global(priority: Int(DispatchQoS.QoSClass.userInitiated.rawValue)).async {
            let fs = self.filterContentForSearchText(searchText)
            DispatchQueue.main.async {
                self.filteredSymbols = fs

                self.searchActive = true

                self.alphabeticSymbolCollection.reloadData()
            }
        }
    }

}

转换前的语法:

func searchBar(searchBar: UISearchBar, textDidChange searchText: String) {

    if searchText == "" {
        self.filteredSymbols = self.symbols
        self.alphabeticSymbolCollection.reloadData()
    } else {
        dispatch_async(dispatch_get_global_queue(Int(QOS_CLASS_USER_INITIATED.rawValue), 0)) {
            let fs = self.filterContentForSearchText(searchText)
            dispatch_async(dispatch_get_main_queue()) {
                self.filteredSymbols = fs

                self.searchActive = true

                self.alphabeticSymbolCollection.reloadData()
            }
        }
    }

}

Answer 1

简直就是

DispatchQueue.global(qos: .userInitiated).async { }