var favorite = ["swim","hamburgers","dogs"];
var itemIndex = 0;
fixScreen();
onEvent("next", "click", function( ) {
    itemIndex++;
    if (itemIndex > (favorite.length - 1)) {
      itemIndex = 0;
    }
    fixScreen();

});
onEvent("last", "click", function( ) {
    itemIndex--;
    if (itemIndex < 0) {
      itemIndex = favorite.length -1 ;
    }
    fixScreen();

});
onEvent("add", "click", function( ) {
  var idkw = getText("text_input1");
  insertItem(favorite, itemIndex, idkw);
  fixScreen();
});


function fixScreen() {
  setText("text_area1", favorite[itemIndex]);
  setText("page", (itemIndex + 1)+ " of " + favorite.length);
}