HTML5 Canvas Mobile Scrolling and Native Events with Konva

By default Konva will prevent default behaviour off all pointer interactions with a stage.
That will prevent unexpected scrolling of a page when you are trying to drag&drop a shape on a mobile device.

But in some cases you may want to keep default behaviour of browser events. In that case you may set preventDefault property of a shape to false.

Instructions: if you are on mobile device try to scroll a page by each rectangle.
Green - should prevent default behaviour (no page scrolling).
Red - will keep default behaviour (scrolling should work).

Konva Mobile Scrolling Demoview raw

<!DOCTYPE html>
<html>
  <head>
    <script src="https://unpkg.com/[email protected]/konva.min.js"></script>
    <meta charset="utf-8" />
    <title>Konva Mobile Scrolling and Native Events Demo</title>
    <style>
      body {
        margin: 0;
        padding: 0;
        overflow: hidden;
        background-color: #f0f0f0;
      }
    </style>
  </head>
  <body>
    <div id="container"></div>
    <script>
      var width = window.innerWidth;
      var height = window.innerHeight;

      var stage = new Konva.Stage({
        container: 'container',
        width: width,
        height: height,
      });

      var layer = new Konva.Layer();

      var defaultBehaviourRect = new Konva.Rect({
        width: 100,
        height: 100,
        fill: 'green',
      });
      layer.add(defaultBehaviourRect);

      var noPreventDefaultRect = new Konva.Rect({
        x: 200,
        y: 50,
        width: 100,
        height: 100,
        fill: 'red',
        preventDefault: false,
      });

      layer.add(noPreventDefaultRect);

      // add the layer to the stage
      stage.add(layer);
    </script>
  </body>
</html>

Enjoying Konva? Please consider to support the project.