IGListKit/Examples/Examples-iOS/IGListKitExamples/ViewControllers/LoadMoreViewController.swift
Ryan Nystrom 316fbe2b8b Remove NSObject+IGListDiffable category
Summary: Removing the category entirely (recreated for unit tests and examples). Went through and updated all of Instagram so we don't rely on the category and found a few models that needed cleaning up.

Reviewed By: jessesquires

Differential Revision: D4206552

fbshipit-source-id: ee8147e8872ea19f6c8bd8072df61eed5bffb6f3
2016-11-21 16:59:00 -08:00

84 lines
3 KiB
Swift

/**
Copyright (c) 2016-present, Facebook, Inc. All rights reserved.
The examples provided by Facebook are for non-commercial testing and evaluation
purposes only. Facebook reserves all rights not expressly granted.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
FACEBOOK BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
import UIKit
import IGListKit
final class LoadMoreViewController: UIViewController, IGListAdapterDataSource, UIScrollViewDelegate {
lazy var adapter: IGListAdapter = {
return IGListAdapter(updater: IGListAdapterUpdater(), viewController: self, workingRangeSize: 0)
}()
let collectionView = IGListCollectionView(frame: .zero, collectionViewLayout: UICollectionViewFlowLayout())
lazy var items = Array(0...20)
var loading = false
let spinToken = "spinner"
override func viewDidLoad() {
super.viewDidLoad()
view.addSubview(collectionView)
adapter.collectionView = collectionView
adapter.dataSource = self
adapter.scrollViewDelegate = self
}
override func viewDidLayoutSubviews() {
super.viewDidLayoutSubviews()
collectionView.frame = view.bounds
}
//MARK: IGListAdapterDataSource
func objects(for listAdapter: IGListAdapter) -> [IGListDiffable] {
var objects = items as [IGListDiffable]
if loading {
objects.append(spinToken as IGListDiffable)
}
return objects
}
func listAdapter(_ listAdapter: IGListAdapter, sectionControllerFor object: Any) -> IGListSectionController {
if let obj = object as? String, obj == spinToken {
return spinnerSectionController()
} else {
return LabelSectionController()
}
}
func emptyView(for listAdapter: IGListAdapter) -> UIView? { return nil }
//MARK: UIScrollViewDelegate
func scrollViewWillEndDragging(_ scrollView: UIScrollView, withVelocity velocity: CGPoint, targetContentOffset: UnsafeMutablePointer<CGPoint>) {
let distance = scrollView.contentSize.height - (targetContentOffset.pointee.y + scrollView.bounds.height)
if !loading && distance < 200 {
loading = true
adapter.performUpdates(animated: true, completion: nil)
DispatchQueue.global(qos: .default).async {
// fake background loading task
sleep(2)
DispatchQueue.main.async {
self.loading = false
let itemCount = self.items.count
self.items.append(contentsOf: Array(itemCount..<itemCount + 5))
self.adapter.performUpdates(animated: true, completion: nil)
}
}
}
}
}