JanC

NSObject *test;
NSArray *someArray = @[ @1, @2, @3 ]; // sample array

[someArray enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
    test = obj;
}];

JanC

NSOperation *operation = [[NSOperation alloc] init];
operation.completionBlock = ^{
    if (operation.isCancelled) {
      // do something
    }
};

JanC

NSOperation *operation = [[NSOperation alloc] init];
__weak typeof(operation) weakOperation = operation;
operation.completionBlock = ^{
    __strong typeof(operation) strongOperation = weakOperation;
    if (strongOperation.isCancelled) {
      // do something
    }
};

JanC

import SwiftUI


/// If _anything_ changes in the `MainView` (e.g. Timer update), its `var body` is re-created and therefore a new instance of `DetailsView(presenter: DetailsViewPresenter())` is created (even if it is already pushed)

/// A new instance of `DetailsViewPresenter` has `isChecked` set to false so the checkbox is unchecked even if view is already presented
struct MainView: View {
    let timer = Timer.publish(every: 1, on: .main, in: .common).autoconnect()
    let formatter:  DateFormatter = {

JanC

import SwiftUI
import Combine

struct MyContentView: View {
    @State var isPresentingModal = false

    // comment this out
     @Environment(\.presentationMode) var presentationMode: Binding<PresentationMode>