Initialize my little module

Hi guys, I have a little problem that is making me crazy... I create my little module but when I try to initialize it at the application start nothing happen... btw it works fine if I call the function by clic on button.

Here is the module:

var width = Ti.Platform.displayCaps.platformWidth - 40;
 
//Dimensione riquadri
var cellWidth = width*0.33;
var cellHeight = width*0.33;
 
//Distanze
var xSpacer = 10;
var ySpacer = 10;
 
//Griglia
var xGrid = 3;
var yGrid = 5;
 
//Colori
var colorSet = ["#D44646","#46D463","#46D4BE","#C2D446","#D446D5","#4575D5","#E39127","#879181","#E291D4"];
 
 
function setGalleryGrid(imageAmount) {
    if(imageAmount > 15) {
        yGrid = Math.ceil(imageAmount/xGrid);
    }
 
    //inizializza
    var tableData = [];
    var cellIndex = 0;
    var colorSetIndex = 0;
 
    for (var y=0; y<yGrid; y++){
        var thisRow = Ti.UI.createTableViewRow({
            className: "grid",
            layout: "horizontal",
            height: cellHeight+(2*ySpacer),
            backgroundSelectedColor:"red"
        });
 
        for (var x=0; x<xGrid; x++){
            var thisView = Ti.UI.createImageView({
                objName:"grid-view",
                objIndex:cellIndex.toString(),
                backgroundColor: colorSet[colorSetIndex],
                //image: "/images/photo.png",
                borderRadius:10,
                left: ySpacer,
                height: cellHeight,
                width: cellWidth
            });
 
            var thisLabel = Ti.UI.createLabel({
                color:"white",
                font:{fontSize:48,fontWeight:'bold'},
                text:cellIndex.toString(),
                touchEnabled:false
            });
 
            thisView.add(thisLabel);
            thisRow.add(thisView);
            cellIndex++;
            colorSetIndex++;
 
            if( colorSetIndex === colorSet.length ){
                colorSetIndex = 0;
            }
        }
        tableData.push(thisRow);
    }
    return tableData;
}
 
module.exports = setGalleryGrid;

function setGrid(pics){
    if(typeof pics == 'undefined') {
        pics = 0;
    }
    var setGalleryGrid = require('JS/onGalleryGrid');
    $.galleryGrid.data = new setGalleryGrid(pics);
};
 
function inizializzaGallery(){
    var width = Ti.Platform.displayCaps.platformWidth;
    var height = 0.95*width;
 
    setGrid();   // <<<--- IT DOESN'T WORK
};
 
inizializzaGallery();  // CALL ON APPLICATION START
 
 
$.settingButton.addEventListener('click',function(e){
    setGrid();   // <<<--- IT WORKS
});

Regards, Matteo