Birds

//All images in this app come from Code.organd are
//Creative Commons free to use 
var namesList = getColumn("100 Birds of the World", "Name");
var colorsList = getColumn("100 Birds of the World", "Primary Color");
var birdImageList = getColumn("100 Birds of the World", "Image of Bird");
var index = 0;

//Filtered Lists
var filternameList = [];
var filterbirdImageList = [];

onEvent("colorDropDown", "click", function( ) {
  var color = getText("colorDropDown");
  createFilteredList(color);
});

onEvent("leftButton", "click", function( ) {
  index = index - 1;
  updatescreen();
});

onEvent("rightButton", "click", function( ) {
  index = index + 1;
  updatescreen();
});

function createFilteredList(color) {
filterbirdImageList = [];
filternameList = [];
  for (var i = 0; i < colorsList.length; i++) {
    if (color == colorsList[i]) {
      appendItem(filterbirdImageList, birdImageList[i]);
      appendItem(filternameList, namesList[i]);
    }
  }
console.log(filternameList); 
updatescreen();
}

function updatescreen(){
  if (index > 0 && index < filternameList.length){
    setImageURL("birdImage", filterbirdImageList[index]);
    setText("nameLabel", filternameList[index]);
  } else {
    index = 0;
    setImageURL("birdImage", filterbirdImageList[index]);
    setText("nameLabel", filternameList[index]);
  }
}

//forgot to call the function "updatescreen"