Java 8 Convert a simple List to Map

import java.util.function.*; import java.util.*; public class Main { public static void main(String[] args) { List<Integer> newList = new ArrayList<Integer>(); newList.add(1); newList.add(2); newList.add(3); newList.add(4); Map<Integer,String> formMap = new LinkedHashMap<Integer,String>(); Function<Integer,Map<Integer,String>> myFunc = i->{ if(i%2==0) { formMap.put(i,”even”); } return formMap; }; Map<Integer,String> newMap = newList.stream().map(i->myFunc.apply(i)).collect(Collectors.toMap( entry -> entry.getKey(), // keyMapper entry -> entry.getValue(), // valueMapper (first, second)…

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React Navigation – undefined is not an object (evaluating ‘this.navigation.navigate’)

I am following this tutorial to implement a switch navigator for user authentication: https://snack.expo.io/@react-navigation/auth-flow-v3. However, this.navigation.navigate appears to undefined when I try to navigate to the next screen. undefined is not an object (evaluating ‘this.props.navigation.navigate’) I am using expo for my app, and I’ve already looked at the solutions posted to a similar question at…

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