HTML5 Canvas Cancel Event Bubble Propagation with Konva

To cancel event bubble propagation with Konva, we can set the cancelBubble property of the Event object to true.

Instructions: Click on the circle to observe that only the circle event binding is handled because the event propagation was canceled when the circle event was triggered, therefore preventing the event object from bubbling upwards.

Vanilla

import Konva from 'konva';

const stage = new Konva.Stage({
  container: 'container',
  width: window.innerWidth,
  height: window.innerHeight,
});

const layer = new Konva.Layer();
stage.add(layer);

const circle = new Konva.Circle({
  x: stage.width() / 2,
  y: stage.height() / 2,
  radius: 70,
  fill: 'red',
  stroke: 'black',
  strokeWidth: 4,
});

circle.on('click', function (evt) {
  alert('You clicked on the circle');
  // stop event bubble
  evt.cancelBubble = true;
});

layer.on('click', function () {
  alert('You clicked on the layer');
});

layer.add(circle);

React

import { Stage, Layer, Circle } from 'react-konva';

const App = () => {
  const handleCircleClick = (e) => {
    alert('You clicked on the circle');
    // stop event bubble
    e.cancelBubble = true;
  };

  const handleLayerClick = () => {
    alert('You clicked on the layer');
  };

  return (
    <Stage width={window.innerWidth} height={window.innerHeight}>
      <Layer onClick={handleLayerClick}>
        <Circle
          x={window.innerWidth / 2}
          y={window.innerHeight / 2}
          radius={70}
          fill="red"
          stroke="black"
          strokeWidth={4}
          onClick={handleCircleClick}
        />
      </Layer>
    </Stage>
  );
};

export default App;

Vue

<template>
  <v-stage :config="stageSize">
    <v-layer @click="handleLayerClick">
      <v-circle
        :config="circleConfig"
        @click="handleCircleClick"
      />
    </v-layer>
  </v-stage>
</template>

<script setup>
const stageSize = {
  width: window.innerWidth,
  height: window.innerHeight
};

const circleConfig = {
  x: window.innerWidth / 2,
  y: window.innerHeight / 2,
  radius: 70,
  fill: 'red',
  stroke: 'black',
  strokeWidth: 4
};

const handleCircleClick = (e) => {
  alert('You clicked on the circle');
  // stop event bubble
  e.cancelBubble = true;
};

const handleLayerClick = () => {
  alert('You clicked on the layer');
};
</script>