[Scripting Question] Animating a picture

[Izanagi987]

Hi Guys, i have a little problem with animating a Pokeball for my Starter Selection Screen.
I am working with a spritesheet with 4 frames and woud like the Pokeball to animate when it is selected. I am working with the Advanced Starter Selection Script by shiney.
I also looked into the Xtransceiver script by KleinStudios but cant really seem to figure out hov animating the parts work.
My script looks like this:

  @sprites["ball_1"]=IconSprite.new(0,0,@viewport)
  @sprites["ball_1"].setBitmap("Graphics/Pictures/StarterSelection/ball1")
  @sprites["ball_1"].src_rect.width = @sprites["ball_1"].bitmap.width/4
  @sprites["ball_1"].src_rect.height = @sprites["ball_1"].bitmap.height
  @sprites["ball_1"].x=146
  @sprites["ball_1"].y=163
  @sprites["ball_1"].opacity=0
  @ballcount=0

 def openscene
   @sprites["bg"].opacity=255
   @sprites["bag"].opacity=255
   @sprites["ball_1"].opacity=255
   @sprites["ball_2"].opacity=255
   @sprites["ball_3"].opacity=255
   @sprites["select"].opacity=255
   pbWait(1)
   self.update
   self.gettinginput
   self.input_action
 end
 def update
   @ballcount+=1
   if select=1
    if @ballcount==8
     @sprites["ball_1"].src_rect.x = @sprites["ball_1"].src_rect.width
    elsif @ballcount==16
     @sprites["ball_1"].src_rect.x = @sprites["ball_1"].src_rect.width*2
    elsif @ballcount==24
     @sprites["ball_1"].src_rect.x = @sprites["ball_1"].src_rect.width*3
    elsif @ballcount==32
     @sprites["ball_1"].src_rect.x = @sprites["ball_1"].src_rect.width*4
    elsif @ballcount==48 
     @sprites["ball_1"].src_rect.width
     @ballcount=0
    end
   end
 end

I only copied the relevant blocks to make the reading easier. I will also attach an image of the ball sprite sheet.
Would really appreciate some help even if its just a hint as to which sections i should look into.

 

[Izanagi987]

Has anyone got an idea? Really struggling with that part...