Javascript canvas: Set own color for two different objects (squares) -


i'm real frustrated problem. so, have following simple code:

var canvas = document.getelementbyid('canvasfield'); var ctx = canvas.getcontext('2d');  function square(x, y, sizeofside) {      this.draw = function () {         ctx.beginpath();         ctx.moveto(x,y);         ctx.lineto(x + sizeofside, y);         ctx.lineto(x + sizeofside, y + sizeofside);         ctx.lineto(x, y + sizeofside);         ctx.lineto(x,y);         ctx.closepath();         ctx.stroke();     }      this.setcolor = function (color) {         ctx.fillstyle = color;         ctx.fill();     } }

square object. can draw square , can set fill-color it. next code works fine. 

var square1 = new square(100, 100, 100); var square2 = new square(250, 200, 100); square1.draw(); square1.setcolor('green'); square2.draw(); square2.setcolor('yellow');

https://i.stack.imgur.com/gz50k.png

but if change this: 

var square1 = new square(100, 100, 100); var square2 = new square(250, 200, 100); square1.draw(); square2.draw();  square1.setcolor('green'); square2.setcolor('yellow');

it breaks down:

https://i.stack.imgur.com/qeojl.png

it seems me understand reason. 2 objects have same context. , square2 sets color yellow context , square1 loses color. maybe not right. expected 2 independent objects , i'll able manipulate conditions @ place in code. have no idea next. please help!

demo

var canvas = document.getelementbyid('canvasfield');  var ctx = canvas.getcontext('2d');    function square(x, y, sizeofside) {        this.draw = function () {          ctx.beginpath();          ctx.moveto(x,y);          ctx.lineto(x + sizeofside, y);          ctx.lineto(x + sizeofside, y + sizeofside);          ctx.lineto(x, y + sizeofside);          ctx.lineto(x,y);          ctx.closepath();          ctx.stroke();      }        this.setcolor = function (color) {          this.draw();          ctx.fillstyle = color;          ctx.fill();      }  }    //var square1 = new square(100, 100, 100);  //var square2 = new square(250, 200, 100);  //square1.draw();  //square1.setcolor('green');  //square2.draw();  //square2.setcolor('yellow');    var square1 = new square(100, 100, 100);  var square2 = new square(250, 200, 100);    //square1.draw();  //square2.draw();    square1.setcolor('green');  square2.setcolor('yellow');
canvas {   border : 2px dotted blue;  }
<canvas id='canvasfield' width=500 height=500></canvas>

call draw function of object inside setcolor function. draw square first fill using given color.


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