Can't add an other view to a slider on android.

Hello,

Why issn't it possible to add another view to a slider view on android? I need to add two images on a slider, on IOS this works just fine but on android it does not work. Here is my code:

var slider = Titanium.UI.createSlider({
        min: info.leftvalue,
        max: info.rightvalue,
        top: 0,
        height: 50,
        width: Titanium.Platform.displayCaps.platformWidth-10,
        thumbImage: "../../images/blank.png",
        leftTrackImage: "../../images/slider-l.png",
        rightTrackImage: "../../images/slider-l.png"
    });
    var leftAnker = Ti.UI.createImageView({
        image: "../../images/vertical-line.png",
        left: (info.leftpos/100)*slider.width+5,
        width: 1,
        height: 30
    });
    slider.add(leftAnker);
    var rightAnker = Ti.UI.createImageView({
        image: "../../images/vertical-line.png",
        left: (info.rightpos/100)*slider.width-5,
        width: 1,
        height: 30
    });
    slider.add(rightAnker);

off course i add this slider to the view.. So my question is: How do i add an image view to a slider view, and can i change the thumbimage on Android?