change annotations text box coordinates from relative to absolute

i am making a gui, in which, i have to move my textboxes according to slider. for that, i need to convert the position coordinates of the text box from relative to absolute.. how to do it? or any other way of doing it, without using text boxes? this can also function well if i open the figure window in full screen mode by default. how to do it? maxfig(f,1) didnt work. or probably i might not be using a correct syntax in that case.. Please Help.