Change slider's next and previous button to be previews of upcoming or previous pictures
12:22 25 Jan 2015

I have a slider and I need to change the next and previous button backgrounds to show a preview of the next and previous slide.

I don't know if it's possible without jQuery but since I'm working on an all JavaScript slider I'd very much appreciate a JavaScript solution

This is the HTML


    

And the Javascript

  nrSlide=3;
  function Load(){
    nrShown = 0;
    vect = new Array(nrSlide + 1);
    vect[0] = document.getElementById("slide1");
    vect[0].style.visibility = "visible";
    for (var i = 1; i < nrSlide; i++)
    {
      vect[i] = document.getElementById("slide" + (i+1));
    }
  }
  function next(){
    nrShown++;
    if(nrShown == nrSlide) {
      nrShown=0;
    }
    Effect();
  }
  function prev(){
    nrShown--;
    if(nrShown == -1) {
      nrShown = nrSlide -1;
    }
    Effect();
  }
  // Effect
  function Effect(){
    for (var i=0; i < nrSlide; i++){
      vect[i].style.opacity = "0";
      vect[i].style.visibility = "hidden";
    }
    vect[nrShown].style.opacity = "1";
    vect[nrShown].style.visibility = "visible";
  }
javascript html slider