Rails combine 4 arrays and sort the resulting array by “created_at”

Question

So I am trying to combine 4 arrays of different items and then sort those arrays by the column "created_at" as in newest first. So the resulting array should be an array of all those items sorted so that the newest item is the first no matter what type they are. I can sort it so that the newest item but it sorts through each type of item and then start sorting the other type.

Example: the types are shirts and pants. I upload a shirt at 10:00pm and then a pant at 10:15pm and then again a shirt at 10:30pm. The array should be like (shirt(10:30), pant(10:15), shirt(10:00)) but instead I get a (shirt(10:00), shirt(10:30), pant(10:15))

Here is my code:

@tops = Top.first(15)
@bottoms = Bottom.first(15)
@footwears = Footwear.first(15)
@accs = Accessory.first(15)

@tempItems = []
@temp = []
@temp = @tempItems + @tops 
@temp = @temp + @bottoms 
@temp = @temp + @footwears 
@temp = @temp + @accs

@temp.sort_by{ |temp| - temp.created_at.to_i}
@itemss = @temp.first(15)

Answer 1

You need to assign the sorted array back to @temp

...

@temp =  @temp.sort_by{ |temp| - temp.created_at.to_i}

Answer 2

You can reduce the confusion by getting rid of unnecessary assignment code:

fifteen= [Top, Bottom, FootWear, Accessory].
  flat_map{ |c| c.first(15) }.
  sort_by{ |e| -e.created_at.to_i }.
  first(15)