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iOS Swift Basics (retired) Collections Modifying an Array

Ray Scales
Ray Scales
613 Points
Posted by Ray Scales
Ray Scales
613 Points

Is there something wrong with the checking software? Why is the following syntax returning an error message?

The following syntax: todo.insert("Learn iOS", atIndex: 1) is returning the following error message which reads "Your 'todo' variable has the wrong value in it." I was told to insert "Learn iOS" element in the second position.

arrays.swift 
var todo = ["Learn Swift", "Build App", "Deploy App"]
todo += ["Debug App", "Fix Bugs"]
todo.removeAtIndex(3)
let item = ["Deploy App"]
todo.insert("Learn iOS", atIndex: 1)

1 Answer

Stone Preston
Stone Preston
42,016 Points
Stone Preston
Stone Preston
42,016 Points

your code for task 2 is incorrect. task 2 states Now that we have to fix bugs in our app we cannot deploy it. Please remove the third item ("Deploy App") and assign it to a constant named item.

you have 

todo.removeAtIndex(3)
let item = ["Deploy App"]

however this removes the 4th item (index 3) instead of the third item (index 2). you also assigned item an array, however its supposed to just be the item that was removed from the array (a String)

according to the documentation, swift arrays have a method called removeAtIndex:

removeAtIndex(_:)

Removes the element at the given index and returns it.

so we can remove the item and assign that item that was removed to a constant in one step:

var todo = ["Learn Swift", "Build App", "Deploy App"]
// task 1
todo.append ("Debug App")
todo.append ("Fix Bugs")
// task 2
let item = todo.removeAtIndex(2)
// task 3
todo.insert("Learn iOS", atIndex:1)