For draw image to canvas
_drawImage("my_canvas","my_image");
For create text to canvas
_drawText("my_canvas","Lamhot Simamora");
For draw line to canvas
_drawLine("my_canvas",30,12,40,60);
For draw circle to canvas
_drawCircle("my_canvas",100,100,100,100);
For clear canvas
_clearCanvas("my_canvas");