vue-konva

v3.1.2

Published

2 months ago

Vue binding to canvas element via Konva framework

Downloads

126,608

0High
0Medium
0Low

lavrton

rafaesc92

vue konva canvas

Vue Konva

ReactKonva Logo

Vue Konva is a JavaScript library for drawing complex canvas graphics using Vue.

It provides declarative and reactive bindings to the Konva Framework.

All vue-konva components correspond to Konva components of the same name with the prefix 'v-'. All the parameters available for Konva objects can add as config in the prop for corresponding vue-konva components.

Core shapes are: v-rect, v-circle, v-ellipse, v-line, v-image, v-text, v-text-path, v-star, v-label, v-path, v-regular-polygon. Also you can create custom shape.

To get more info about Konva you can read Konva Overview.

Documentation / live edit

See Tutorials page

Quick Start

Vue.js version 2.4+ is required.

1 Install via npm

vue@3:

npm install vue-konva konva --save

vue@2:

npm install vue-konva@2 konva --save

2 Import and use VueKonva

vue@3:

import { createApp } from 'vue';
import App from './App.vue';
import VueKonva from 'vue-konva';

const app = createApp(App);
app.use(VueKonva);
app.mount('#app');

vue@2:

import Vue from 'vue';
import VueKonva from 'vue-konva';

Vue.use(VueKonva);

3 Reference in your component templates

<template>
  <v-stage :config="configKonva">
    <v-layer>
      <v-circle :config="configCircle"></v-circle>
    </v-layer>
  </v-stage>
</template>

<script>
export default {
  data() {
    return {
      configKonva: {
        width: 200,
        height: 200
      },
      configCircle: {
        x: 100,
        y: 100,
        radius: 70,
        fill: "red",
        stroke: "black",
        strokeWidth: 4
      }
    };
  }
};

</script>

Or use a CDN

<html>
  <head>
    <meta charset="utf-8" />
    <meta
      name="viewport"
      content="width=device-width, initial-scale=1, shrink-to-fit=no"
    />
    <meta http-equiv="x-ua-compatible" content="ie=edge" />
  </head>
  <body>
    <div id="app">
      <v-stage ref="stage" :config="configKonva">
        <v-layer ref="layer">
          <v-circle :config="configCircle"></v-circle>
        </v-layer>
      </v-stage>
    </div>
    <!--1. Link Vue Javascript & Konva-->
    <script src="https://unpkg.com/vue/dist/vue.js"></script>
    <script src="https://unpkg.com/konva/konva.js"></script>
    <!--2. Link VueKonva Javascript -->
    <script src="https://unpkg.com/vue-konva/umd/vue-konva.min.js"></script>
    <script>
      // 3. Create the Vue instance
      new Vue({
        el: '#app',
        data: {
          configKonva: {
            width: 200,
            height: 200,
          },
          configCircle: {
            x: 100,
            y: 100,
            radius: 70,
            fill: 'red',
            stroke: 'black',
            strokeWidth: 4,
          },
        },
      });
    </script>
  </body>
</html>

Core API

Getting reference to Konva objects

You can use ref feature from vue.

<template>
  <v-stage ref="stage">
    <v-layer ref="layer">
      <v-rect ref="rect" />
    </v-layer>
  </v-stage>
</template>

<script>
  const width = window.innerWidth;
  const height = window.innerHeight;

  export default {
    mounted() {
      const stage = this.$refs.stage.getNode();
      const layer = this.$refs.layer.getNode();
      const rect = this.$refs.rect.getNode();
    },
  };
</script>

Strict mode

By default vue-konva works in "non-strict" mode. If you changed a property manually (or by user action like drag&drop) properties of the node will be not matched with properties passed as config. vue-konva updates ONLY changed properties.

In strict mode vue-konva will update all properties of the nodes to the values that you provided in config, no matter changed they or not.

You should decide what mode is better in your actual use case.

To enable strict mode pass __useStrictMode attribute:

<v-rect :config="{}" __useStrictMode></v-rect>

Configurable prefix

By default vue-konva is using v- prefix for all components.

You can use your own prefix if default one conflicts with some other libs or your components.

import Vue from 'vue';
import VueKonva from 'vue-konva'

Vue.use(VueKonva, { prefix: 'Konva'});

// in template:
<konva-stage ref="stage" :config="stage">

Custom Konva Nodes

By passing a Record<string, new (...args: any) => Node<any>> object to customNodes in options, you can use your own konva node classes in Vue Konva.

import Vue from 'vue';
import VueKonva from 'vue-konva'

class MyRect extends Konva.Rect {
  constructor() {
    super()
    console.log('MyRect')
  }
}

Vue.use(VueKonva, {
    // The keys are used as component names.
    customNodes: { MyRect }
})

// in template:
<v-my-rect />

Change log

The change log can be found on the Releases page.