Cfrgtkky

I have a very weird array and I am not sure what I am missing, something very simple I am sure. Here is my code, This code loops a struct with arrays of objects and variables and attempts to find the objects which category = 1, when this is true, it sends the array of objects into another array. Everything works fine, until I try to copy the array into the sorted array, more comments in code. I am trying to sort a tableView when the user clicks a certain category, the 4 possible categories are 1,30,31,32 (don't ask why)

var courses = [Course]()

var sortedCourses = [Course]()

@objc func catOthersButtonObj(_ sender: UIButton){ //<- needs `@objc`

    var count = 0

    let courseCount = courses.count

    let otherCat = 1



    // set count to loop the number of detected arrays

    // this category looks for the number 1



    print("courseCount = " + String(courseCount)) // to debug if courseCount is accurate, it is

    //let noOfCat = courses.categories.count



    while (count < courseCount)

    {



        print("count = " + String(count)) // to debug if count is increasing every loop, it is

        let totalNoCat = (courses[count].categories?.count)!

        var catCount = 0



        // while entering a loop of arrays of objects, it searches for the array "categories" and sets totalNoCat = number of categories, this is neccesary because one object can have many categories

        // catCount is used to loop through the number of detect categories



        if (totalNoCat == 0)

        {

            break

        }



        // If no categories is detected, next array



        while (catCount < totalNoCat)

        {

            print("totalNoCat = " + String(totalNoCat))

            print("catCount = " + String(catCount))



            // debug, check if totalNoCat is detected

            // debug, catCount if number of categories is detected and added

            if (courses[count].categories?[catCount] == otherCat)

            {

                print("category Detected = " + String((courses[count].categories?[catCount])!))

                // see if category is 1, when it is 1, this is triggered, so its working fine

                let currentNoSortedCourses = sortedCourses.count

                print("currentNoSortedCourses = " + String(currentNoSortedCourses))

                // check the number of sorted array, this is to add array into the next array

                // if there is 0 number of sorted arrays, then sorted[0] should be course[detectarray category = 0 array]

                //print(courses[count]) checks if courses[count] has data, it does

                sortedCourses[currentNoSortedCourses] = courses[count] //where the error is

                //here it is sortedCourses[0] = courses[7] ( 7 is which the array detected the correct category

                break

            }

            catCount = catCount + 1

            print("Category Detected = " + String((courses[count].categories?[catCount - 1])!))



            //debug, if category not 1, show what it is



        }

        count = count + 1

    }



}

Print results



courseCount = 50

count = 0

totalNoCat = 2

catCount = 0

Category Detected = 31

totalNoCat = 2

catCount = 1

Category Detected = 30

count = 1

totalNoCat = 2

catCount = 0

Category Detected = 31

totalNoCat = 2

catCount = 1

Category Detected = 30

count = 2

totalNoCat = 1

catCount = 0

Category Detected = 30

count = 3

totalNoCat = 2

catCount = 0

Category Detected = 32

totalNoCat = 2

catCount = 1

Category Detected = 30

count = 4

totalNoCat = 2

catCount = 0

Category Detected = 32

totalNoCat = 2

catCount = 1

Category Detected = 30

count = 5

totalNoCat = 1

catCount = 0

Category Detected = 32

count = 6

totalNoCat = 2

catCount = 0

Category Detected = 32

totalNoCat = 2

catCount = 1

Category Detected = 30

count = 7

totalNoCat = 1

catCount = 0

category Detected = 1

currentNoSortedCourses = 0

Without going much into the structure of the code and how it can be written in a more "Swifty" way, I can see the problem is that this is not a good way to append to an array in Swift.

            let currentNoSortedCourses = sortedCourses.count

            sortedCourses[currentNoSortedCourses] = courses[count]

This is accessing an index that is out of bounds and causes a crash. To append to an array in Swift use append method.

        sortedCourses.append(courses[count])

Whilst I'm here I might as well tell you that a better way (one liner) to solve your problem probably be something like this

    sortedCourses = courses.filter { $0.categories.contains(1) }