Canvas responsive media screen min-width - FabricJS

Question

I trying adjust canvas for each resolution, so I first using css and put medias screens for each resolution.

@media screen and (min-width: 320px) {
  #c {   -webkit-transform : scale(0.38);
-webkit-transform-origin : 0 0; }

https://jsfiddle.net/qj3oyzs8/

It work for me, but all object not drag, resize or rotable properly. One solution is apply zoomOut and zoomIn, eg:

http://jsfiddle.net/Q3TMA/662/

Now I need help for know How capture resolution for open correctly canvas scale in the browser

---

EDIT

function screencan() {
   var widthscrencan = (window.innerWidth > 0) ? window.innerWidth : screen.width;

/*

In if has to have the same scale the css
@media screen and (min-width: 320px) {
  #c {   -webkit-transform : scale(0.38);
-webkit-transform-origin : 0 0; }
}


*/
    if(widthscrencan <= 360 ) {
           // Zoom Out


 function zoomOut() {
        // TODO limit max cavas zoom out

        canvasScale = canvasScale / SCALE_FACTOR;

        canvas.setHeight(canvas.getHeight() * (1 / SCALE_FACTOR));
        canvas.setWidth(canvas.getWidth() * (1 / SCALE_FACTOR));

        var objects = canvas.getObjects();
        for (var i in objects) {
            var scaleX = objects[i].scaleX;
            var scaleY = objects[i].scaleY;
            var left = objects[i].left;
            var top = objects[i].top;

            var tempScaleX = scaleX * (1 / SCALE_FACTOR);
            var tempScaleY = scaleY * (1 / SCALE_FACTOR);
            var tempLeft = left * (1 / SCALE_FACTOR);
            var tempTop = top * (1 / SCALE_FACTOR);

            objects[i].scaleX = tempScaleX;
            objects[i].scaleY = tempScaleY;
            objects[i].left = tempLeft;
            objects[i].top = tempTop;

            objects[i].setCoords();
        }

        canvas.renderAll();        
    }

    }               
 }
 window.onload = screencan;

It not work

Thanks for any help

Answer 1

Happy !!! I got it :D

The only problem is that for a new resizing the browser move. It will be necessary to refresh the page, because window.onload = zoomIn;

Solution! I removed queryes screen of the css and:

widthscrencan = (window.innerWidth > 0) ? window.innerWidth : screen.width; // capture width screen onload
canvasScale = 1; //global  

   if (widthscrencan <=360){ 

      function zoomIn() {
          var SCALE_FACTOR = .37;
          canvasScale = canvasScale * SCALE_FACTOR;

      canvas.setHeight(canvas.getHeight() * SCALE_FACTOR);
      canvas.setWidth(canvas.getWidth() * SCALE_FACTOR);

      var objects = canvas.getObjects();
      for (var i in objects) {
          var scaleX = objects[i].scaleX;
          var scaleY = objects[i].scaleY;
          var left = objects[i].left;
          var top = objects[i].top;

          var tempScaleX = scaleX * SCALE_FACTOR;
          var tempScaleY = scaleY * SCALE_FACTOR;
          var tempLeft = left * SCALE_FACTOR;
          var tempTop = top * SCALE_FACTOR;

          objects[i].scaleX = tempScaleX;
          objects[i].scaleY = tempScaleY;
          objects[i].left = tempLeft;
          objects[i].top = tempTop;

          objects[i].setCoords();
      }


      canvas.renderAll();
      alert(widthscrencan+' function 360'); 

  }

   window.onload = zoomIn;
 }






   if ((widthscrencan >=361) || (widthscrencan ==768)){ 

            function zoomIn768() {
          var SCALE_FACTOR = .45;
          canvasScale = canvasScale * SCALE_FACTOR;

          canvas.setHeight(canvas.getHeight() * SCALE_FACTOR);
          canvas.setWidth(canvas.getWidth() * SCALE_FACTOR);

          var objects = canvas.getObjects();
          for (var i in objects) {
              var scaleX = objects[i].scaleX;
              var scaleY = objects[i].scaleY;
              var left = objects[i].left;
              var top = objects[i].top;

              var tempScaleX = scaleX * SCALE_FACTOR;
              var tempScaleY = scaleY * SCALE_FACTOR;
              var tempLeft = left * SCALE_FACTOR;
              var tempTop = top * SCALE_FACTOR;

              objects[i].scaleX = tempScaleX;
              objects[i].scaleY = tempScaleY;
              objects[i].left = tempLeft;
              objects[i].top = tempTop;

              objects[i].setCoords();
          }


          canvas.renderAll();
          alert(widthscrencan+' function 768'); 


        }
          window.onload = zoomIn768;
    }

   if ((widthscrencan >=769) || (widthscrencan ==992)){ 

            function zoomIn992() {
          var SCALE_FACTOR = .5;
          canvasScale = canvasScale * SCALE_FACTOR;

          canvas.setHeight(canvas.getHeight() * SCALE_FACTOR);
          canvas.setWidth(canvas.getWidth() * SCALE_FACTOR);

          var objects = canvas.getObjects();
          for (var i in objects) {
              var scaleX = objects[i].scaleX;
              var scaleY = objects[i].scaleY;
              var left = objects[i].left;
              var top = objects[i].top;

              var tempScaleX = scaleX * SCALE_FACTOR;
              var tempScaleY = scaleY * SCALE_FACTOR;
              var tempLeft = left * SCALE_FACTOR;
              var tempTop = top * SCALE_FACTOR;

              objects[i].scaleX = tempScaleX;
              objects[i].scaleY = tempScaleY;
              objects[i].left = tempLeft;
              objects[i].top = tempTop;

              objects[i].setCoords();
          }


          canvas.renderAll();
          alert(widthscrencan+' function 992'); 


        }
          window.onload = zoomIn992;
    }

      if ((widthscrencan >=993) || (widthscrencan ==1200)){ 

            function zoomIn1200() {
          var SCALE_FACTOR = .9;
          canvasScale = canvasScale * SCALE_FACTOR;

          canvas.setHeight(canvas.getHeight() * SCALE_FACTOR);
          canvas.setWidth(canvas.getWidth() * SCALE_FACTOR);

          var objects = canvas.getObjects();
          for (var i in objects) {
              var scaleX = objects[i].scaleX;
              var scaleY = objects[i].scaleY;
              var left = objects[i].left;
              var top = objects[i].top;

              var tempScaleX = scaleX * SCALE_FACTOR;
              var tempScaleY = scaleY * SCALE_FACTOR;
              var tempLeft = left * SCALE_FACTOR;
              var tempTop = top * SCALE_FACTOR;

              objects[i].scaleX = tempScaleX;
              objects[i].scaleY = tempScaleY;
              objects[i].left = tempLeft;
              objects[i].top = tempTop;

              objects[i].setCoords();
          }


          canvas.renderAll();
          alert(widthscrencan+' function 1200'); 


        }
          window.onload = zoomIn1200;
    }


      if (widthscrencan >=1300){ 

            function zoomIn1300() {
          var SCALE_FACTOR = 1.01;
          canvasScale = canvasScale * SCALE_FACTOR;

          canvas.setHeight(canvas.getHeight() * SCALE_FACTOR);
          canvas.setWidth(canvas.getWidth() * SCALE_FACTOR);

          var objects = canvas.getObjects();
          for (var i in objects) {
              var scaleX = objects[i].scaleX;
              var scaleY = objects[i].scaleY;
              var left = objects[i].left;
              var top = objects[i].top;

              var tempScaleX = scaleX * SCALE_FACTOR;
              var tempScaleY = scaleY * SCALE_FACTOR;
              var tempLeft = left * SCALE_FACTOR;
              var tempTop = top * SCALE_FACTOR;

              objects[i].scaleX = tempScaleX;
              objects[i].scaleY = tempScaleY;
              objects[i].left = tempLeft;
              objects[i].top = tempTop;

              objects[i].setCoords();
          }


          canvas.renderAll();
          alert(widthscrencan+' function 1300'); 


        }
          window.onload = zoomIn1300;
    }

Answer 2

Instead Of Using OR operation I used AND Operation and it worked perfect for me
here is the modified code of yours

Thanks. :)

 var canvas = new fabric.Canvas('c'); canvas.backgroundColor = "#Ffaafa"; var widthscrencan = (window.innerWidth > 0) ? window.innerWidth : screen.width; // capture width screen onload var canvasScale = 1; //global var SCALE_FACTOR = 1.2; window.onload = function () { var text = new fabric.Text('Text Here', { left: 100, top: 50 }); canvas.add(text); if (widthscrencan <=360){ zoomIn(); } else if ((widthscrencan >=361) && (widthscrencan <= 768)){ zoomIn768(); } else if ((widthscrencan >=769) && (widthscrencan <= 992)){ zoomIn992(); } else if ((widthscrencan >=993) && (widthscrencan <= 1200)){ zoomIn1200(); } else if (widthscrencan >=1300){ zoomIn1300(); } }; function zoomIn() { var SCALE_FACTOR = .37; canvasScale = canvasScale * SCALE_FACTOR; canvas.setHeight(canvas.getHeight() * SCALE_FACTOR); canvas.setWidth(canvas.getWidth() * SCALE_FACTOR); var objects = canvas.getObjects(); for (var i in objects) { var scaleX = objects[i].scaleX; var scaleY = objects[i].scaleY; var left = objects[i].left; var top = objects[i].top; var tempScaleX = scaleX * SCALE_FACTOR; var tempScaleY = scaleY * SCALE_FACTOR; var tempLeft = left * SCALE_FACTOR; var tempTop = top * SCALE_FACTOR; objects[i].scaleX = tempScaleX; objects[i].scaleY = tempScaleY; objects[i].left = tempLeft; objects[i].top = tempTop; objects[i].setCoords(); } canvas.renderAll(); alert('Display Area Width : '+widthscrencan+'px Function Called zoomIn'); } function zoomIn768() { var SCALE_FACTOR = .45; canvasScale = canvasScale * SCALE_FACTOR; canvas.setHeight(canvas.getHeight() * SCALE_FACTOR); canvas.setWidth(canvas.getWidth() * SCALE_FACTOR); var objects = canvas.getObjects(); for (var i in objects) { var scaleX = objects[i].scaleX; var scaleY = objects[i].scaleY; var left = objects[i].left; var top = objects[i].top; var tempScaleX = scaleX * SCALE_FACTOR; var tempScaleY = scaleY * SCALE_FACTOR; var tempLeft = left * SCALE_FACTOR; var tempTop = top * SCALE_FACTOR; objects[i].scaleX = tempScaleX; objects[i].scaleY = tempScaleY; objects[i].left = tempLeft; objects[i].top = tempTop; objects[i].setCoords(); } canvas.renderAll(); alert('Display Area Width : '+widthscrencan+'px Function Called zoomIn768'); } function zoomIn992() { var SCALE_FACTOR = .5; canvasScale = canvasScale * SCALE_FACTOR; canvas.setHeight(canvas.getHeight() * SCALE_FACTOR); canvas.setWidth(canvas.getWidth() * SCALE_FACTOR); var objects = canvas.getObjects(); for (var i in objects) { var scaleX = objects[i].scaleX; var scaleY = objects[i].scaleY; var left = objects[i].left; var top = objects[i].top; var tempScaleX = scaleX * SCALE_FACTOR; var tempScaleY = scaleY * SCALE_FACTOR; var tempLeft = left * SCALE_FACTOR; var tempTop = top * SCALE_FACTOR; objects[i].scaleX = tempScaleX; objects[i].scaleY = tempScaleY; objects[i].left = tempLeft; objects[i].top = tempTop; objects[i].setCoords(); } canvas.renderAll(); alert('Display Area Width : '+widthscrencan+'px Function Called zoomIn992'); } function zoomIn1200() { var SCALE_FACTOR = .9; canvasScale = canvasScale * SCALE_FACTOR; canvas.setHeight(canvas.getHeight() * SCALE_FACTOR); canvas.setWidth(canvas.getWidth() * SCALE_FACTOR); var objects = canvas.getObjects(); for (var i in objects) { var scaleX = objects[i].scaleX; var scaleY = objects[i].scaleY; var left = objects[i].left; var top = objects[i].top; var tempScaleX = scaleX * SCALE_FACTOR; var tempScaleY = scaleY * SCALE_FACTOR; var tempLeft = left * SCALE_FACTOR; var tempTop = top * SCALE_FACTOR; objects[i].scaleX = tempScaleX; objects[i].scaleY = tempScaleY; objects[i].left = tempLeft; objects[i].top = tempTop; objects[i].setCoords(); } canvas.renderAll(); alert('Display Area Width : '+widthscrencan+'px Function Called zoomIn1200'); } function zoomIn1300() { var SCALE_FACTOR = 1.01; canvasScale = canvasScale * SCALE_FACTOR; canvas.setHeight(canvas.getHeight() * SCALE_FACTOR); canvas.setWidth(canvas.getWidth() * SCALE_FACTOR); var objects = canvas.getObjects(); for (var i in objects) { var scaleX = objects[i].scaleX; var scaleY = objects[i].scaleY; var left = objects[i].left; var top = objects[i].top; var tempScaleX = scaleX * SCALE_FACTOR; var tempScaleY = scaleY * SCALE_FACTOR; var tempLeft = left * SCALE_FACTOR; var tempTop = top * SCALE_FACTOR; objects[i].scaleX = tempScaleX; objects[i].scaleY = tempScaleY; objects[i].left = tempLeft; objects[i].top = tempTop; objects[i].setCoords(); } canvas.renderAll(); alert('Display Area Width : '+widthscrencan+'px Function Called zoomIn1300'); }

 <canvas id="c" width="800" height="550"></canvas> <script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script> <script src="http://cdnjs.cloudflare.com/ajax/libs/fabric.js/3.6.1/fabric.min.js"></script>