Group in Vue Diagram component

18 Dec 202324 minutes to read

Group is used to cluster multiple nodes and connectors into a single element. It acts like a container for its children (nodes, groups, and connectors). Every change made to the group also affects the children. Child elements can be edited individually.

Create group

Add group when initializing diagram

A group can be added to the diagram model through nodes collection. To define an object as group, add the child objects to the children collection of the group. The following code illustrates how to create a group node.

• The padding property of a group node defines the spacing between the group node’s edges and its children.

• While creating group, its child node need to be declared before the group declaration.

• Add a node to the existing group child by using the diagram.group method.

• The group’s diagram.unGroup method is used to define whether the group can be ungrouped or not.

• A group can be added into a child of another group.

app.vue

<template>
    <div id="app">
        <ejs-diagram id="diagram"  :width='width' :height='height' :nodes='nodes' :getNodeDefaults='getNodeDefaults' ></ejs-diagram>
    </div>
</template>
<script>
    import Vue from 'vue';
    import { DiagramPlugin } from '@syncfusion/ej2-vue-diagrams';
    Vue.use(DiagramPlugin);
    let nodes = [{
        id: "rectangle1",
        offsetX: 100,
        offsetY: 100,
        width: 100,
        height: 100,
        annotations: [{
            content: 'rectangle1'
        }]
    },
    {
        id: "rectangle2",
        offsetX: 200,
        offsetY: 200,
        width: 100,
        height: 100,
        annotations: [{
            content: 'rectangle2'
        }]
    },
    {
        id: "rectangle3",
        offsetX: 400,
        offsetY: 300,
        width: 100,
        height: 100,
        style: {
            fill: 'darkCyan',
            strokeWidth: 2
        },
        annotations: [{
            content: 'rectangle2'
        }]
    }
    // Grouping node 1 and node 2 into a single group
    {
        id: 'group',
        children: ['rectangle1', 'rectangle2'],
        padding:{left:10,right:10,top:10,bottom:10}
    }
]
export default {
    name: 'app'
    data() {
        return {
            width: "100%",
            height: "350px",
            nodes: nodes,
            getNodeDefaults: (node) => {
                node.height = 100;
                node.width = 100;
                node.style.fill = '#6BA5D7';
                node.style.strokeColor = 'white';
                return node;
            },
        }
    }
    mounted: function() {
        let diagramInstance: Diagram;
        let diagramObj: any = document.getElementById("diagram");
        diagramInstance = diagramObj.ej2_instances[0];
        diagramInstance.selectAll();
        // Adding the third node into the existing group
        diagramInstance.group();
    }
}
</script>
<style>
    @import "../../node_modules/@syncfusion/ej2-vue-diagrams/styles/material.css";
</style>

The following code illustrates how a ungroup at runtime.

app.vue

<template>
    <div id="app">
        <ejs-diagram id="diagram"  :width='width' :height='height' :nodes='nodes' :getNodeDefaults='getNodeDefaults' ></ejs-diagram>
    </div>
</template>
<script>
    import Vue from 'vue';
    import { DiagramPlugin } from '@syncfusion/ej2-vue-diagrams';
    Vue.use(DiagramPlugin);
    let nodes = [{
        id: "rectangle1",
        offsetX: 100,
        offsetY: 100,
        width: 100,
        height: 100,
        annotations: [{
            content: 'rectangle1'
        }]
    }, {
        id: "rectangle2",
        offsetX: 200,
        offsetY: 200,
        width: 100,
        height: 100,
        annotations: [{
            content: 'rectangle2'
        }]
    },
    {
        id: 'group',
        children: ['rectangle1', 'rectangle2']
    },
]
export default {
    name: 'app'
    data() {
        return {
            width: "100%",
            height: "350px",
            nodes: nodes,
            getNodeDefaults: (node) => {
                node.height = 100;
                node.width = 100;
                node.style.fill = '#6BA5D7';
                node.style.strokeColor = 'white';
                return node;
            },
        }
    }
    mounted: function() {
        let diagramInstance: Diagram;
        let diagramObj: any = document.getElementById("diagram");
        diagramInstance = diagramObj.ej2_instances[0];
        diagramInstance.selectAll();
        // Ungroup the selected group into nodes
        diagramInstance.unGroup();
    }
}
</script>
<style>
    @import "../../node_modules/@syncfusion/ej2-vue-diagrams/styles/material.css";
</style>

Add group at runtime

A group node can be added at runtime by using the client-side method diagram.add.

The following code illustrates how a group node is added at runtime.

app.vue

<template>
    <div id="app">
        <ejs-diagram id="diagram"  :width='width' :height='height' :nodes='nodes' :getNodeDefaults='getNodeDefaults'></ejs-diagram>
    </div>
</template>
<script>
    import Vue from 'vue';
    import { DiagramPlugin,NodeModel } from '@syncfusion/ej2-vue-diagrams';
    Vue.use(DiagramPlugin);
    let nodes = [{
    id: "rectangle1",
    offsetX: 100,
    offsetY: 100,
    width: 100,
    height: 100,
    annotations: [{
        content: 'rectangle1'
    }]
},
{
    id: "rectangle2",
    offsetX: 200,
    offsetY: 200,
    width: 100,
    height: 100,
    annotations: [{
        content: 'rectangle2'
    }]
}];
let group: NodeModel = {
    id: 'group2',
    children: ['rectangle1', 'rectangle2']
};
export default {
    name: 'app'
    data() {
        return {
            width: "100%",
            height: "350px",
            nodes: nodes,
            getNodeDefaults: (node) => {
                node.height = 100;
                node.width = 100;
                node.style.fill = '#6BA5D7';
                node.style.strokeColor = 'white';
                return node;
            },
        }
    }
    mounted: function() {
        let diagramInstance: Diagram;
        let diagramObj: any = document.getElementById("diagram");
        diagramInstance = diagramObj.ej2_instances[0];
        diagramInstance.selectAll();
        // Add the group into the diagram
        diagramInstance.add(group);
    }
}
</script>
<style>
    @import "../../node_modules/@syncfusion/ej2-vue-diagrams/styles/material.css";
</style>

Add children To group at runtime

A childNode can be added to the specified Group at runtime by utilizing the client-side method diagramInstance.addChildToGroup.

This functionality is achieved by passing the group and existing children as arguments to the method.

The following code illustrates how a child node and a group node can be passed as arguments to the method and executed at runtime.

diagramInstance.addChildToGroup(groupNode, childNode);

Remove children from group at runtime

A specific child from a group node can be removed at runtime by utilizing the client-side method diagramInstance.removeChildFromGroup .

This functionality is achieved by passing the group and its children as arguments to the method.

The following code illustrates how a child node is removed from a group at runtime.

diagramInstance.removeChildFromGroup (groupNode, childNode);

app.vue

<template>
    <div id="app">
        <button @click="addChild">addChild</button>
        <button @click="removeChild">removeChild</button>
        <ejs-diagram id="diagram"  :width='width' :height='height' :nodes='nodes'></ejs-diagram>
    </div>
</template>
<script>
    import Vue from 'vue';
    import { DiagramPlugin } from '@syncfusion/ej2-vue-diagrams';
    Vue.use(DiagramPlugin);
    let diagramInstance;
    let node = {
        id: 'node1', width: 150, height: 100, offsetX: 100, offsetY: 100, annotations: [{ content: 'Node1' }]
    };
    let node2 = {
        id: 'node2', width: 80, height: 130, offsetX: 200, offsetY: 200, annotations: [{ content: 'Node2' }]
    };
    let group = {
        id: 'group1', children: ['node1', 'node2']
    };
    let node3 = {
        id: 'node3', width: 100, height: 100, offsetX: 300, offsetY: 300, annotations: [{ content: 'Node3' }]
    };
export default {
    name: 'app',
    data() {
        return {
            width: "100%",
            height: "450px",
            nodes: [node,node2,node3,group],
        }
    },   
    mounted: function() {
        let diagramObj = document.getElementById("diagram");
        diagramInstance = diagramObj.ej2_instances[0];
    },
    methods: {
        addChild: function () {
            diagramInstance.addChildToGroup(group, 'node3');
        },
        removeChild: function () {
            diagramInstance.removeChildFromGroup(group, 'node3');
        },

    },
}
</script>
<style>
    @import "../../node_modules/@syncfusion/ej2-vue-diagrams/styles/material.css";
</style>

Container

Containers are used to automatically measure and arrange the size and position of the child elements in a predefined manner. There are two types of containers available.

Canvas

• The canvas panel supports absolute positioning and provides the least layout functionality to its contained diagram elements.

• Canvas allows you to position its contained elements by using the margin and alignment properties.

• Rendering alone possible in canvas container.

• It allows elements to be either vertically or horizontally aligned.

• Child can be defined with the collection canvas.children property.

• Basic element can be defined with the collection of basicElements.

Stack

• Stack panel is used to arrange its children in a single line or stack order, either vertically or horizontally.

• It controls spacing by setting margin properties of child and padding properties of group. By default, a stack panel’s orientation is vertical.

The following code illustrates how to add a stack panel.

app.vue

<template>
    <div id="app">
        <ejs-diagram id="diagram"  :width='width' :height='height' :nodes='nodes' :setNodeTemplate='setNodeTemplate' :getNodeDefaults="getNodeDefaults"></ejs-diagram>
    </div>
</template>
<script>
    import Vue from 'vue';
    import { DiagramPlugin, NodeModel,StackPanel,TextElement } from '@syncfusion/ej2-vue-diagrams';
    Vue.use(DiagramPlugin);
    let count = 11;
    function getTextElement(text: string){
        let textElement: TextElement = new TextElement();
        textElement.id = "text" + count;
        textElement.width = 50;
        textElement.height = 20;
        textElement.content = text;
        count++;
        return textElement;
        }
    function addRows(column: StackPanel){
        column.children.push(getTextElement('Row1'));
        column.children.push(getTextElement('Row2'));
        column.children.push(getTextElement('Row3'));
        column.children.push(getTextElement('Row4'));
        }
    let nodes = [
        {
            id: 'node5',
            width: 100,
            height: 100,
            offsetX: 100,
            offsetY: 100,
            style: {
                strokeColor: '#6BA5D7',
                fill: '#6BA5D7'
            },
            annotations: [{
                content: 'Custom Template',
                offset: {
                    y: 1
                },
                verticalAlignment: 'Top'
            }]
        }
    ]
    export default {
        name: 'app'
        data () {
            return {
                width: "100%",
                height: "350px",
                nodes: nodes,
                getNodeDefaults: (node: NodeModel) => {
        node.height = 100;
        node.width = 100;
        node.style.fill = '#6BA5D7';
        node.style.strokeColor = 'white';
        return node;
    },
    setNodeTemplate: (obj: NodeModel, diagram: Diagram): StackPanel => {
        if (obj.id.indexOf('node5') !== -1) {
            // It will be replaced with grid panel
            let table: StackPanel = new StackPanel();
            table.orientation = 'Horizontal';
            table.padding.left
            let column1: StackPanel = new StackPanel();
            column1.children = [];
            column1.children.push(getTextElement('Column1'));
            addRows(column1);
            let column2: StackPanel = new StackPanel();
            column2.children = [];
            column2.children.push(getTextElement('Column2'));
            addRows(column2);
            table.children = [column1, column2];
            return table;
        }
        return null;
    },
            }
        }
    }
</script>
<style>
    @import "../../node_modules/@syncfusion/ej2-vue-diagrams/styles/material.css";
</style>

Difference between a basic group and containers

Group	Container
It arranges the child elements based on the child elements position and size properties.	Each container has a predefined behavior to measure and arrange its child elements. Canvas and stack containers are supported in the diagram.
The Padding, Min, and Max Size properties are not applicable for basic group.	It is applicable for container.
The Children’s margin and alignment properties are not applicable for basic group.	It is applicable for container.

Interaction

You can edit the group and its children at runtime. For more information about how to interact with a group, refer to Edit Groups.

See Also

• How to add annotations to the node
• How to add ports to the node
• How to enable/disable the behavior of the node
• How to add nodes to the symbol palette
• How to create diagram nodes using drawing tools
• How to perform the interaction on the group