https://github.com/jdisho/Papr/issues/55

This pull makes possible interactively (with gesture) to close detail photo

I did some changes on Coordinator pop function. I made it cancelable (when dispose the observable do not set current controller)

First of all I would like to thank you for this amazing project. Truly your project has become an educational resource for me!

My question is about the SceneCoordinator. I implemented the Coordinator with the same logic without RX, because I don't have the enough confidence to start using RX in projects for production. I have only one missing link to intercept when the View Controllers pop or a tab bar item is changed you make the SceneCoordinator the navigationControllerDelegate and tabBarControllerDelegate. I am wondering what the difference between this:

currentViewController.navigationController?.rx.delegate.setForwardToDelegate(self, retainDelegate: false)
currentViewController.tabBarController?.rx.delegate.setForwardToDelegate(self, retainDelegate: false)

And this code is:

currentViewController.navigationController?.delegate = self
currentViewController.tabBarController?.delegate = self

I'm guessing RX has a fancy way of preventing memory leaks in this case. How can I make my own implementation of setForwardToDelegate? Again thank you very much!

If any of the image requests get an error response, it will crash since binding error. Catch error and return an empty observable or a placeholder image to avoid the crash.

git clone https://github.com/jdisho/Papr.git cd Papr pod install open Papr.xcworkspace

and cmd+R compile failed ? Has anyone encountered this problem ?

Papr/Coodinator/SceneCoodinator.swift

static func actualViewController(for viewController: UIViewController) -> UIViewController {
    var controller = viewController
    if let tabBarController = controller as? UITabBarController {
        guard let selectedViewController = tabBarController.selectedViewController else {
            return tabBarController
        }
        controller = selectedViewController
    }
    if let navigationController = viewController as? UINavigationController {
        return navigationController.viewControllers.first!
    }
    -return viewController  
    +return controller
}

https://github.com/jdisho/Papr/issues/43

@jdisho fixes RxDataSources crashes with a custom UICollectionViewLayout

When image cell sets image we update the PinterestLayout sizes with that size and invalidate the layout

If app is runned from Xcode, it is all ok, otherwise app will do nothing because can't obtain Unsplash Constants from Enviroment Variables. See https://stackoverflow.com/a/14214923 .

Closes issue #96

This PR converts all SVG images added for iOS 13 to support SFSymbols to PDF. This way we can still use them as vector images. For each medium/small size and medium/regular weight an image was set in the assets accordingly.

Known issue while working on PR:

App crashes still on iOS 12.2 in the HomeViewController on line 82:

outputs.isRefreshing
.execute { [weak self] isRefreshing in
    if isRefreshing {
        self?.collectionView.scrollToItem(at: IndexPath(item: 0, section: 0), at: .top, animated: false)
        self?.collectionView.setContentOffset(CGPoint(x: 0.0, y: -(self?.refreshControl.frame.height ?? 0.0)), animated: true)
    } else {
        self?.collectionView.setContentOffset(.zero, animated: true)
    }
}
.bind(to: refreshControl.rx.isRefreshing)
.disposed(by: disposeBag)

Commenting out the isRefreshing code solves the problem as the app crashes on scrolling logic.

Since SVG format is not supported in iOS, the app crashes when it tries to access an image with a given resource name.

static var arrowUpRight: UIImage {
    if #available(iOS 13.0, *) {
        return UIImage(systemName: "arrow.up.right", withConfiguration: symbolConfigurationMedium)!#
    }
    return UIImage(imageLiteralResourceName: "arrow.up.right") // #CRASH
}

We can solve this issue by (I would like to avoid having a dependency for this use case) by converting the SVGs into .png or supporting iOS13 and higher.

Thoughts on this @serjooo (since you closed #89) ?

(This app is not planned to be released, so supporting only the latest iOS version seems fine to me.)

We could add pan gesture recogniser on DetailsScreen and dismiss the photo interactively

https://github.com/HeroTransitions/Hero/wiki/Interactive-Transition

@jdisho wdyt

I will be cool if we could implement parallax images scroll

https://github.com/jdisho/ParallaxScrolling

(images in each cell moves with different speed than the scroll)

I imitated your code. After I press the select button, isLikedByUser is always the initial value.

PostViewCellModel.swift

import Foundation
import RxSwift
import Action
import RealmSwift

protocol PostViewCellModelInput {
    var selectPostAction: Action<Post, Post> { get }
    var unselectPostAction: Action<Post, Post> { get }
}
protocol PostViewCellModelOutput {
    var postData: Observable<Post> { get }
    var isSelected: Observable<Bool> { get }
}
protocol PostViewCellModelType {
    var inputs: PostViewCellModelInput { get }
    var outputs: PostViewCellModelOutput { get }
}

final class PostViewCellModel: PostViewCellModelType, PostViewCellModelInput, PostViewCellModelOutput {
    var inputs: PostViewCellModelInput { return self }
    var outputs: PostViewCellModelOutput { return self }
    
    lazy var selectPostAction: Action<Post, Post> = {
        Action<Post, Post> { [unowned self] post in
            let configuration = Realm.Configuration(deleteRealmIfMigrationNeeded: true)
            let realm = try! Realm(configuration: configuration)
            
            let sharePost = SharePost()
            sharePost.ref = post.ref!
            sharePost.title = post.title
            sharePost.summary = post.summary
            sharePost.url = post.url

            try! realm.write {
                realm.add(sharePost, update: .modified)
            }

            return .just(post)
        }
    }()
    
    lazy var unselectPostAction: Action<Post, Post> = {
        Action<Post, Post> { [unowned self] post in
            let configuration = Realm.Configuration(deleteRealmIfMigrationNeeded: true)
            let realm = try! Realm(configuration: configuration)
            let sharePost = realm.objects(SharePost.self).filter("ref = %@", post.ref!)
            
            if (sharePost.count > 0) {
                try! realm.write {
                    realm.delete(sharePost.first!)
                }
            }
            
            return .just(post)
        }
    }()
 
    var postData: Observable<Post>
    var isSelected: Observable<Bool>
    
    private let service: PostServiceType
    private let cache: Cache
    private let sceneCoordinator: SceneCoordinatorType
    
    init(post: Post, service: PostServiceType = PostService(), cache: Cache = Cache.shared, sceneCoordinator: SceneCoordinatorType = SceneCoordinator.shared) {
        self.service = service
        self.cache = cache
        self.sceneCoordinator = sceneCoordinator
        
        postData = Observable.just(post)
        let cachedPostData = cache.getObject(ofType: Post.self, withId: post.ref ?? "").unwrap()
        
        isSelected = self.postData.merge(with: cachedPostData)
            .map { post in
                let configuration = Realm.Configuration(deleteRealmIfMigrationNeeded: true)
                let realm = try! Realm(configuration: configuration)

                if realm.object(ofType: SharePost.self, forPrimaryKey: post.ref!) != nil {
                    return true
                } else {
                    return false
                }
            }.unwrap()
    }
}

PostViewCell.swift

import Foundation
import UIKit
import RxSwift
import RxCocoa
import RealmSwift

class PostViewCell: UITableViewCell, BindableType, NibIdentifiable & ClassIdentifiable {
    var viewModel: PostViewCellModelType!
    
    @IBOutlet var selectButton: UIButton!
    
    private var disposeBag = DisposeBag()

    func bindViewModel() {
        let inputs = viewModel.inputs
        let outputs = viewModel.outputs
        
        Observable.combineLatest(outputs.isSelected, outputs.postData)
            .bind { [weak self] in
                self?.selectButton.rx.bind(to: $0 ? inputs.unselectPostAction: inputs.selectPostAction, input: $1)
            }
            .disposed(by: disposeBag)

        outputs.isSelected
            .map { $0 ? UIColor.init(red: 210 / 255, green: 233 / 255, blue: 1, alpha: 1) : .clear }
            .bind(to: self.rx.backgroundColor)
            .disposed(by: disposeBag)
    }
}

As @serjooo mentioned:

App crashes still on iOS 12 in the HomeViewController on line 82:

outputs.isRefreshing
.execute { [weak self] isRefreshing in
    if isRefreshing {
        self?.collectionView.scrollToItem(at: IndexPath(item: 0, section: 0), at: .top, animated: false)
        self?.collectionView.setContentOffset(CGPoint(x: 0.0, y: -(self?.refreshControl.frame.height ?? 0.0)), animated: true)
    } else {
        self?.collectionView.setContentOffset(.zero, animated: true)
    }
}
.bind(to: refreshControl.rx.isRefreshing)
.disposed(by: disposeBag)

Commenting out the isRefreshing code solves the problem as the app crashes on scrolling logic.

On the photo detail, swipe left-right to see the prev-next photo. This means that the PhotoDetail.swift should be a UICollectionViewCell instead of a UIViewController.