IGListKit/Example/IGListKitExamples/ViewControllers/LoadMoreViewController.swift
Valeriy Van c9ca112eef Applies trailing block syntax.
Summary:
Applies trailing block syntax.

- [x] All tests pass. Demo project builds and runs.
- [ ] I added tests, an experiment, or detailed why my change isn't tested.
- [x] I have reviewed the [contributing guide](https://github.com/Instagram/IGListKit/blob/master/CONTRIBUTING.md)
Closes https://github.com/Instagram/IGListKit/pull/148

Differential Revision: D4111506

Pulled By: rnystrom

fbshipit-source-id: b99f987f25579634a515786533d9ef2f2e4cd6bd
2016-11-01 10:59:21 -07:00

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
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 = NSObject()
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)
}
return objects
}
func listAdapter(_ listAdapter: IGListAdapter, sectionControllerFor object: Any) -> IGListSectionController {
if let obj = object as? NSObject, 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)
}
}
}
}
}