c# - slider event not firing windows 8.1 and windows phone 8.1 -

i building simple media player using mediaelement in windows 8.1 . working fine(play ,pause,player progress). using timer show progess of media in slider. problem there no event dragging thumb of slider. have tried manipulationsompleted,dragenter,pointerpressed events. none of events firing. please tell em how can control position of mediaelment using slider thumb dragging.

thanks..