vue-cytoscape

Cytoscape, now in vue

Usage

Add it to your project:

yarn add vue-cytoscape

then import the plugin in your main Vue instance:

import VueCytoscape from 'vue-cytoscape'
import 'vue-cytoscape/dist/vue-cytoscape.css'
...
Vue.use(VueCytoscape)

After this, you use cytoscape as a normal vue component:

<cytoscape :config="config"/>

The config property is the part of the object passed to the cytoscape function without the container property. For example:

const config = {
  elements: [
    { // node a
      data: { id: 'a' }
    }, { // node b
      data: { id: 'b' }
    }, { // edge ab
      data: { id: 'ab', source: 'a', target: 'b' }
    }
  ],
  style: [
    {
      selector: 'node',
      style: {
        'background-color': '#666',
        'label': 'data(id)'
      }
    }, {
      selector: 'edge',
      style: {
        'width': 3,
        'line-color': '#ccc',
        'target-arrow-color': '#ccc',
        'target-arrow-shape': 'triangle'
      }
    }
  ],
  layout: {
    name: 'grid',
    rows: 1
  }
}

For more information please read cytoscape documentation. This library is in a very early stage and suggestions and help are welcomed. If you have any issue please feel free to use the Issues page.

Reactivity

Starting with version 1.2 it is possible to have a more vue-like experience. You can add elements to a cytoscape instance by adding cy-elements components as children of the cytoscape component:

<template>
  <cytoscape :config="config">
    <cy-element
      v-for="def in elements"
      :key="`${def.data.id}`"
      :definition="def"
    />
  </cytoscape>
</template>
<script>
export default {
  data () {
    return {
      elements: [{
          data: { id: 'a' },  position: { x: 589, y: 182 }
        },
        ...
      ]
    }
  }
}
</script>

You can check the ChildrenElementsExample.vue in the github repository for a full example.

How this works

This section is safe to ommit. Nevertheless the way the previous vue-like behaviour is implemented is the following:

• A CyElement is a component that renders an empty div, if you inspect the DOM you will see that vue actually renders them.
• In the created and destroyed lifecycle method of a CyElement component a cytoscape element is added/removed accordingly.
• In the updated method, the correspondent element is first removed from cytoscape and then added back.

Cytoscape events

You can register listeners to the usual cytoscape events directly in the component itself:

<template>
  ...
  <cytoscape :config="config" v-on:mousedown="onCyMouseDown" />
  ...
<template>
<script>
...
export default {
  ...
  methods: {
    onCyMouseDown (event) {
      // this will be called `onmousedown` over cytoscape
    }
  },
  ...
}
</script>

The event is the same event dispatched by cytoscape, see events in cytoscape.

Accesing cytoscape instance

The installation registrate a global cytoscape component and a store object this.$cytoscape. Accessing this.$cytoscape.instance returns a promise to the cytoscape instance. You can access this for example to catch mouse events (although the method of the previous section is preferred) or to perform any action, using the same approach as using vanilla cytoscape. Accessing the store object allows you to add/delete/... objects in cytoscape. For example:

<template>
  <cytoscape :config="config" style="width: 100%; height: 600px"/>
</template>
<script>
// initial config
const config = {
  elements: [],
  style: [ {
    selector: 'node',
    style: {
      ...
    }
    ...
  }],
  layout: {
    ...
  }
}

export default {
...
  methods: {
    // you can call this method somewhere to trigger the update of the cytoscape canvas content
    cyUpdate () {
      // new nodes and edges
      const cynodes = [...]
      const cylinks = [...]
      // update the cytoscape instance
      this.$cytoscape.instance.then(cy => {
        // remove all elements
        cy.remove(cy.elements())
        // add the new ones
        cy.add(cynodes)
        cy.add(cylinks)
        // inside the cytoscape callback we lose the component this, we can use `that` instead if needed
        const that = this
        // click and double click (simulated) over the nodes
        cy.on('tap', 'node', function (event) {
          const data = event.target.data()
          // if you are using vuex you can dispatch your events this way
          that.$store.dispatch('sectors/select', { data })
        })
      })
    }
  }
}
</script>

Internal lifecycle hooks and cytoscape extensions

Many features of cytoscape come as external dependencies or extensions. To use an extension you can use the following life cycle hooks:

• preConfig if defined, it will be called with the cytoscape constructor function before creating the cytoscape instance.
• afterCreate if defined, it will be called after the creation of the cytoscape instance with this instance as argument.

For example, in the following code we register and configure the contextMenus extension:

<template>
  <div id="holder">
    <cytoscape :config="config" :preConfig="preConfig" :afterCreated="afterCreated"/>
  </div>
</template>
<script>
...
import jquery from 'jquery'
import contextMenus from 'cytoscape-context-menus'
import 'cytoscape-context-menus/cytoscape-context-menus.css'

export default {
  ...,
  methods: {
    preConfig (cytoscape) {
      // it can be used both ways
      contextMenus(cytoscape, jquery)
      // cytoscape.use(contextMenus, jquery)
    },
    afterCreated (cy) {
      // demo your core ext
      cy.contextMenus({
        menuItems: [
          {
            id: 'remove',
            content: 'remove',
            tooltipText: 'remove',
            image: {src: 'remove.svg', width: 12, height: 12, x: 6, y: 4},
            selector: 'node, edge',
            onClickFunction: function (event) {
              var target = event.target || event.cyTarget
              target.remove()
            },
            hasTrailingDivider: true
          },
          {
            id: 'hide',
            content: 'hide',
            tooltipText: 'hide',
            selector: '*',
            onClickFunction: function (event) {
              var target = event.target || event.cyTarget
              target.hide()
            },
            disabled: false
          }
        ]
      })
    },..
  },
  ...
}
</script>

For additional details check the ContextMenusExample.vue and CtxMenuExample.vue in the src folder. Notice that these example correspond to different extensions.

Another example, using the cola layout extension can be found in LayoutExtensionsExample.vue.

Changelog

v0.2

• cytoscape events can now be listened in through the component.
• graph elements can be added as children of the cytoscape component.

v0.1

• support for cytoscape interaction via global instance.
• preConfig and afterCreated lifecycle hooks provided, support for cytoscape plugins.