Fit image

Hi guys! How do I fit any image on any resolution device? I tried to use width 100% in imageview, but was larger than the screen. my code:

function Image(){
    WindoOptions = {
        fullscreen : true,
        modal : false,
        navBarHidden : true
    };
 
    var win = Ti.UI.createWindow(WindoOptions);
 
    var images = [];
    var image_url = null;tra
    var image_view = null;
    var container_view = null;
    var activityIndicator = Ti.UI.createActivityIndicator({
        message : "Carregando..."
    });
    win.add(activityIndicator);
    activityIndicator.show();
    var getData = function (){
        var xhr = Ti.Network.createHTTPClient();
 
 
        xhr.onload = function(){
            var tn = JSON.parse(this.responseText);
            for(i=0; i < tn.length; i++){
                container_view = Ti.UI.createView({backgroundColor: "red",});
                image_url= tn[i].foto;
                elWidth = tn[i].size[0] > Ti.Platform.displayCaps.platformWidth ? Ti.Platform.displayCaps.platformWidth : tn[i].size[0];
                image_view = Ti.UI.createImageView({
                    image:image_url,
                    backgroundColor: "blue",
                    width: tn[i].size[0],
                    height : "auto",
                });
 
                container_view.add(image_view);
                images.push(container_view);
            }
 
 
 
            var imageGallery = Titanium.UI.createScrollableView({
                views:images,
                height : Titanium.Platform.displayCaps.platformHeight - 40,
                backgroundColor: "white",
                width : Titanium.Platform.displayCaps.platformWidth,
                contentWidth: Ti.UI.FILL,
                maxZoomScale : 2,
                minZoomScale : 0,
 
            });
 
                win.add(imageGallery);
            activityIndicator.hide();
            return win.open({
                activityEnterAnimation: Ti.Android.R.anim.slide_in_left,
                activityExitAnimation: Ti.Android.R.anim.slide_out_right
           });
 
        }
        xhr.open('GET',"http://localhost/arquivo.json");
        xhr.setRequestHeader('Content-Type', 'application/json');
        xhr.send();
 
 
 
 
    }
    return getData();
 
}
 
module.exports = Image;