How to validate signature pad empty or not in android? -

how validate signature pad empty or not in android?

how can check if signature blank, i.e. pixels transparent?

i must avoid x-y loop on every pixel.

//globally private boolean issignatured = false;  //oncreate msignaturepad.setonsignedlistener(new signaturepad.onsignedlistener() { @override public void onsigned() {    //event triggered when pad signed     issignatured = true; }  @override public void onclear() {    //event triggered when pad cleared } });  //in on click if(issignatured){     //do next process }else{     //intimate sign }