NetNewsWire/Evergreen/BatchUpdate.swift

64 lines
1.0 KiB
Swift

//
// BatchUpdates.swift
// DataModel
//
// Created by Brent Simmons on 9/12/16.
// Copyright © 2016 Ranchero Software, LLC. All rights reserved.
//
import Foundation
public typealias BatchUpdateBlock = () -> Void
public extension Notification.Name {
public static let BatchUpdateDidPerform = Notification.Name(rawValue: "BatchUpdateDidPerform")
}
final class BatchUpdate {
private var count = 0
var isPerforming: Bool {
get {
return count > 0
}
}
func perform(_ batchUpdateBlock: BatchUpdateBlock) {
incrementCount()
batchUpdateBlock()
decrementCount()
}
}
private extension BatchUpdate {
func incrementCount() {
count = count + 1
}
func decrementCount() {
count = count - 1
if count < 1 {
if count < 0 {
assertionFailure("Batch updates count should never be below 0.")
count = 0
}
count = 0
postBatchUpdateDidPerform()
}
}
func postBatchUpdateDidPerform() {
NotificationCenter.default.post(name: .BatchUpdateDidPerform, object: nil, userInfo: nil)
}
}