Slider value.

I have defined a slider in an application (in the Application Builder). I want it to control the time paramater (t) for which some plots will be shown. I have defined a method with a few lines like

Integer ind;
ind = app.form("form1").formObject("slider1").getValue();

The method getValue() is not valid (I wrote just "from the heart", I'm looking for the correct one).

I only need to GET the value of the slider (the step, in my case there are 20 in total) and use it to set the time value and update the plots. Thanks in advance.