Solve on Android (Samsung S3) and other 4.1 systems on the phone Cancas scratch music is invalid

 function drawcircle (id,x,y,r) {                 var ca = document.getelementbyid (ID);                 var cans =  Ca.getcontext ("2d");                 cans.globalCompositeOperation =  "Destination-out";                 cans.beginpath ();                 cans.arc (x,y,r,0,math.pi*2);                 //Solution compatible                  ca.style.display =  ' None ';                 ca.offsetHeight;                 ca.style.display =  ' Inherit ';                  //Solution compatible                  cans.fillstyle= "#000 ";                 cans.fill ();             } This will solve

Reference from: http://bbs.csdn.net/topics/390808206

Solve on Android (Samsung S3) and other 4.1 systems on the phone Cancas scratch music is invalid