java - Blur TextView on click, Android -

i trying blur out textview, when button clicked. far code looks likes this:

 @override     public void onclick(view v) {         float radius = pdf.gettextsize() / 3;         blurmaskfilter filter = new blurmaskfilter(radius, blurmaskfilter.blur.normal);         if (v==pause){             if (paused){                 paused=false;                 pdf.getpaint().setmaskfilter(null);             }             else{                 paused=true;                 pdf.getpaint().setmaskfilter(filter);             }         }     } 

what doing wrong?

just set

 pdf.setlayertype(view.layer_type_software, null); 

befor line: pdf.getpaint().setmaskfilter(filter);