Box
Map
Vue

nodes

Allows you to bind the collection of diagram nodes to a data source. For more information, see the Data Binding section.

Type:

Object

Default Value: null

autoLayout

Specifies an auto-layout algorithm that the UI component uses to build a diagram.

Type:

String

|

Object

Default Value: 'auto'
Accepted Values: 'auto' | 'off' | 'tree' | 'layered'

The layout property is in effect when a diagram is bound to a data source using the nodes property.

View Demo

See Also

autoSizeEnabled

Specifies whether or not a shape size is automatically changed to fit the text when the UI component is bound to a data source.

Type:

Boolean

Default Value: true

NOTE
If the widthExpr and heightExpr properties are specified, the autosize feature is disabled. The UI component displays shapes based on the provided sizes.

containerChildrenExpr

Specifies the name of a data source field or an expression that returns a container's nested items.

Type:

String

|

Function

Function parameters:
data: any

The current node's data object.

value: any

A container's nested items or undefined.

Return Value: any

A container's nested items.

Default Value: undefined

This property is in effect for "verticalContainer" or "horizontalContainer" nodes.

A function assigned to this property should do the following:

  • Return a container's nested items when the value parameter is set to undefined.
  • Save item values to a data storage when the value parameter contains a container's nested items. For instance, assign these values to the obj parameter's field to save a container's nested items in your data source.

You can also use the containerKeyExpr property to provide a container's content.

index.js
data.js
$(function() {
    $("#diagram").dxDiagram({
        nodes: {
            dataSource: new DevExpress.data.ArrayStore({
                key: "this",
                data: orgItems
            }),
            keyExpr: "id",
            parentKeyExpr: "parent_id",
            containerChildrenExpr: "children",
        },

    });
});
var orgItems = [
    {  
        "id":"106",
        "text":"Development",
        "type":"ellipse"
    },
    {  
        "id":"110",
        "text":"ASP.NET Team",
        "type": "horizontalContainer",
        "parent_id": "106",
        "children": [
        {
            "id":"112",
            "text":"Ana\nTrujillo",
            "type":"rectangle",
        },
        {
            "id":"113",
            "text":"Antonio\nMoreno",
            "type":"rectangle",
        }]
    }
];

Diagram - Container

containerKeyExpr

Specifies the name of a data source field or an expression that returns a key of a node's parent container node.

Type:

String

|

Function

Function parameters:
data: any

The current node's data object.

value: any

A node's parent container node or undefined.

Return Value: any

A node's parent container node.

Default Value: 'containerKey'

A function assigned to this property should do the following:

  • Return a node's parent container node when the value parameter is set to undefined.
  • Save a container node value to a data storage when the value parameter contains a node's parent container node. For instance, assign this value to the obj parameter's field to save a node's parent container node in your data source.

The parent container node must be of the "verticalContainer" or "horizontalContainer" type.

You can also use the containerChildrenExpr property to provide a container's content.

index.js
data.js
$(function() {
    $("#diagram").dxDiagram({
        nodes: {
            dataSource: new DevExpress.data.ArrayStore({
                key: "this",
                data: orgItems
            }),
            keyExpr: "id",
            parentKeyExpr: "parent_id",
            containerKeyExpr: "team",
        },

    });
});
var orgItems = [
    {  
        "id":"106",
        "text":"Development",
        "type":"ellipse"
    },
    {  
        "id":"110",
        "text":"ASP.NET Team",
        "type": "horizontalContainer",
        "parent_id": "106",
    },
    {  
        "id":"112",
        "text":"Ana\nTrujillo",
        "type":"rectangle",
        "team": "110"
    },
    {  
        "id":"113",
        "text":"Antonio\nMoreno",
        "type":"rectangle",
        "team": "110"
    },
];

Diagram - Container

customDataExpr

Specifies the name of a data source field or an expression that returns a node's custom data.

Type:

String

|

Function

Function parameters:
data: any

The current node's data object.

value: any

A node's new custom data or undefined.

Return Value: any

A node's custom data.

Default Value: undefined

This property links custom data from a data source to a diagram node. The node contains the linked data copied from the data source. Changes in the data are reflected in the diagram history. You can use the UI to undo and redo these changes.

A function assigned to this property should do the following:

  • Return a node's new custom data when the value parameter is set to undefined.
  • Save a new custom data value to a data storage when the value parameter contains a node's custom data. For instance, assign this value to the obj parameter's field to save a node's custom data in your data source.
jQuery
index.js
data.js
$(() => {
    const store = new DevExpress.data.ArrayStore({
        key: 'ID',
        data: employees,
    });
    $('#diagram').dxDiagram({
        nodes: {
            dataSource: store,
            customDataExpr(obj, value) {
                if (value === undefined)
                    return {
                        Full_Name: obj.Full_Name,
                        Prefix: obj.Prefix,
                        Title: obj.Title,
                    };
                obj.Full_Name = value.Full_Name;
                obj.Prefix = value.Prefix;
                obj.Title = value.Title;
                return null;
            },
            // ...
    });
});
const employees = [
    {
        ID: 1,
        Head_ID: 0,
        Full_Name: 'John Heart',
        Prefix: 'Mr.',
        Title: 'CEO',
    }, 
    {
        ID: 2,
        Head_ID: 1,
        Full_Name: 'Samantha Bright',
        Prefix: 'Dr.',
        Title: 'COO',
    },
    // ... 
}];
Angular
app.component.html
app.module.ts
app.service.ts
<dx-diagram #diagram id="diagram">
    <dxo-nodes
        [dataSource]="dataSource"
        [customDataExpr]="itemCustomDataExpr"
    >
    </dxo-nodes>
</dx-diagram>
import { DxDiagramModule, DxDiagramComponent } from 'devextreme-angular';
import ArrayStore from 'devextreme/data/array_store';
import { Service } from './app.service';

@Component({
    selector: 'app-root',
    templateUrl: 'app/app.component.html',
    styleUrls: ['app/app.component.css'],
    providers: [Service],
})

export class AppComponent {
    dataSource: ArrayStore;

    constructor(service: Service) {
        this.dataSource = new ArrayStore({
            key: 'ID',
            data: service.getEmployees(),
        });
    }

    itemCustomDataExpr(obj, value) {
        if (value === undefined)
            return {
                Full_Name: obj.Full_Name,
                Prefix: obj.Prefix,
                Title: obj.Title,
            };
        obj.Full_Name = value.Full_Name;
        obj.Prefix = value.Prefix;
        obj.Title = value.Title;
    }
}
import { Injectable } from '@angular/core';

export class Employee {
    ID: number;
    Head_ID: number;
    Full_Name: string;
    Prefix: string;
    Title: string;
    }

const employees: Employee[] = [
    {
        ID: 1,
        Head_ID: undefined,
        Full_Name: 'John Heart',
        Prefix: 'Mr.',
        Title: 'CEO',
    },
    {
        ID: 2,
        Head_ID: 1,
        Full_Name: 'Samantha Bright',
        Prefix: 'Dr.',
        Title: 'COO',
    },
    // ...
];

@Injectable()
export class Service {
    getEmployees() {
        return employees;
    }
}
Vue
App.vue
data.js
<template>
    <DxDiagram
        id="diagram"
        ref="diagram"
    >
        <DxNodes
            :data-source="dataSource"
            :custom-data-expr="itemCustomDataExpr"
        />
    </DxDiagram>
</template>
<script>
    import {
        DxDiagram, DxNodes,
    } from 'devextreme-vue/diagram';
    import ArrayStore from 'devextreme/data/array_store';
    import service from './data.js';
    export default {
        components: {
            DxDiagram, DxNodes
        },
        data() {
            return {
                dataSource: new ArrayStore({
                    key: 'ID',
                    data: service.getEmployees(),
                }),
            };
        },
        methods: {
            itemCustomDataExpr(obj, value) {
                if (value === undefined) 
                    return {
                        Full_Name: obj.Full_Name,
                        Prefix: obj.Prefix,
                        Title: obj.Title,
                    };
                obj.Full_Name = value.Full_Name;
                obj.Prefix = value.Prefix;
                obj.Title = value.Title;
                return null;
                },
        },
    };
</script>
const employees = [
    {
        ID: 1,
        Head_ID: 0,
        Full_Name: 'John Heart',
        Prefix: 'Mr.',
        Title: 'CEO',
    },
    {
        ID: 2,
        Head_ID: 1,
        Full_Name: 'Samantha Bright',
        Prefix: 'Dr.',
        Title: 'COO',
    },
    // ...
];

export default {
    getEmployees() {
        return employees;
    },
};
React
App.js
data.js
import React from 'react';
import Diagram, { Nodes } from 'devextreme-react/diagram';
import ArrayStore from 'devextreme/data/array_store';
import service from './data.js';

class App extends React.Component {
    constructor(props) {
        super(props);
        this.dataSource = new ArrayStore({
            key: 'ID',
            data: this.employees,
        });
    }

    itemCustomDataExpr(obj, value) {
        if (value === undefined)
            return {
                Full_Name: obj.Full_Name,
                Prefix: obj.Prefix,
                Title: obj.Title,
            };
        obj.Full_Name = value.Full_Name;
        obj.Prefix = value.Prefix;
        obj.Title = value.Title;
        return null;
    }

    render() {
        return (
        <Diagram id="diagram">
            <Nodes 
                dataSource={this.dataSource} 
                customDataExpr={this.itemCustomDataExpr}>
            </Nodes>
        </Diagram>
        );
    }
}
export default App;
const employees = [
    {
        ID: 1,
        Head_ID: 0,
        Full_Name: 'John Heart',
        Prefix: 'Mr.',
        Title: 'CEO',
    }, 
    {
        ID: 2,
        Head_ID: 1,
        Full_Name: 'Samantha Bright',
        Prefix: 'Dr.',
        Title: 'COO',
    },
    // ...
];

export default {
    getEmployees() {
        return employees;
    },
};

View Demo

dataSource

Binds the nodes collection to the specified data. For more information, see the Data Binding section.

Default Value: null

The Diagram UI component creates a shape for every node in the collection.

heightExpr

Specifies the name of a data source field or an expression that returns a node's height.

Type:

String

|

Function

Function parameters:
data: any

The current node's data object.

value: any

A node's new height or undefined.

Return Value: any

A node's height.

Default Value: undefined

A function assigned to this property should do the following:

  • Return a node's new height when the value parameter is set to undefined.
  • Save a new height value to a data storage when the value parameter contains a node's height. For instance, assign this value to the obj parameter's field to save a node's height in your data source.

The units property specifies the measurement unit.

jQuery
index.js
data.js
$(() => {
    $('#diagram').dxDiagram({
        nodes: {
            dataSource: new DevExpress.data.ArrayStore({
                key: 'id',
                data: orgItems,
            }),
            heightExpr: itemHeightExpr,
            // ...
        },
    });

    function itemHeightExpr(obj, value) {
        if (value === undefined)
            obj.height = value;
        else
            return obj.height || (obj.type === 'group' && 1) || 0.75;
        return null;
    }
});
const orgItems = [
    {
        id: '106',
        name: 'Development',
        type: 'group',
        height: 2,
    },
    {
        id: '112',
        name: 'Ana\nTrujillo',
        level: 'senior',
    },
    // ... 
];
Angular
app.component.html
app.module.ts
app.service.ts
<dx-diagram #diagram id="diagram">
    <dxo-nodes
        [dataSource]="orgItemsDataSource"
        keyExpr="ID"
        [heightExpr]="itemHeightExpr"
    >
    </dxo-nodes>
</dx-diagram>
import { DxDiagramModule, DxDiagramComponent } from 'devextreme-angular';
import ArrayStore from 'devextreme/data/array_store';
import { Service } from './app.service';

@Component({
    selector: 'app-root',
    templateUrl: 'app/app.component.html',
    styleUrls: ['app/app.component.css'],
    providers: [Service],
})

export class AppComponent {
    orgItemsDataSource: ArrayStore;

    constructor(service: Service) {
        this.orgItemsDataSource = new ArrayStore({
            key: 'ID',
            data: service.getOrgItems(),
        });
    }

    itemHeightExpr(obj, value) {
        if (value === undefined)
            obj.Height = value;
        else 
            return obj.Height || (obj.Type === 'group' && 1) || 0.75;
    }
}
import { Injectable } from '@angular/core';

export class OrgItem {
    ID: string;
    Name: string;
    Type?: string;
    Level?: string;
    Height?: string;
}

const orgItems: OrgItem[] = [
    {
        ID: '106',
        Name: 'Development',
        Type: 'group',
        Height: '2',
    },
    {
        ID: '112',
        Name: 'Ana\nTrujillo',
        Level: 'senior',
    },
    // ...
];

@Injectable()
export class Service {
    getOrgItems() {
        return orgItems;
    }
}
Vue
App.vue
data.js
<template>
    <DxDiagram
        id="diagram"
        ref="diagram"
    >
        <DxNodes
            :data-source="orgItemsDataSource"
            :height-expr="itemHeightExpr"
        />
    </DxDiagram>
</template>
<script>
    import {
        DxDiagram, DxNodes,
    } from 'devextreme-vue/diagram';
    import ArrayStore from 'devextreme/data/array_store';
    import service from './data.js';
    export default {
        components: {
            DxDiagram, DxNodes
        },
        data() {
            return {
                orgItemsDataSource: new ArrayStore({
                    key: 'id',
                    data: service.getOrgItems(),
                }),
            };
        },
        methods: {
            itemHeightExpr(obj, value) {
                if (value === undefined)
                    obj.height = value;
                else
                    return obj.height || (obj.type === 'group' && 1) || 0.75;
                return null;
            },
        },
    };
</script>
const orgItems = [
    {
        id: '106',
        name: 'Development',
        type: 'group',
        height: '2'',
    },
    {
        id: '112',
        name: 'Ana\nTrujillo',
        level: 'senior',
    },
    // ...
];

export default {
    getOrgItems() {
        return orgItems;
    },
};
React
App.js
data.js
import React from 'react';
import Diagram, { Nodes } from 'devextreme-react/diagram';
import ArrayStore from 'devextreme/data/array_store';
import service from './data.js';

class App extends React.Component {
    constructor(props) {
        super(props);
        this.orgItemsDataSource = new ArrayStore({
            key: 'id',
            data: service.getOrgItems(),
        });
    }

    render() {
        return (
        <Diagram id="diagram">
            <Nodes dataSource={this.orgItemsDataSource}
                heightExpr={this.itemHeightExpr}
            />
        </Diagram>
        );
    }

    itemHeightExpr(obj, value) {
        if (value === undefined)
            obj.height = value;
        else
            return obj.height || (obj.type === 'group' && 1) || 0.75;
        return null;
    }
}

export default App;
const orgItems = [
    {
        id: '106',
        name: 'Development',
        type: 'group',
        height: '2',
    },
    {
        id: '112',
        name: 'Ana\nTrujillo',
        level: 'senior',
    },
    // ...
];

export default {
    getOrgItems() {
        return orgItems;
    },
};

imageUrlExpr

Specifies the name of a data source field or an expression that returns an image URL or Base64 encoded image for a node.

Type:

String

|

Function

Function parameters:
data: any

The current node's data object.

value: any

An image URL or Base64 encoded image for a node or undefined.

Return Value: any

An image URL or Base64 encoded image for a node.

Default Value: undefined

This property is in effect for nodes of the "cardWithImageOnLeft", "cardWithImageOnTop", or "cardWithImageOnRight" type.

A function assigned to this property should do the following:

  • Return an image URL or Base64 encoded image when the value parameter is set to undefined.
  • Save a new URL or image value to a data storage when the value parameter contains an image URL or Base64 encoded image. For instance, assign this value to the obj parameter's field to save an image URL or Base64 encoded image for a node in your data source.

index.js
data.js
    $(function() {
        $("#diagram").dxDiagram({
            nodes: {
                dataSource: new DevExpress.data.ArrayStore({
                    key: "this",
                    data: orgItems
                }),
                imageUrlExpr: "picture",
            },
            edges: {
                dataSource: new DevExpress.data.ArrayStore({
                    key: "this",
                    data: orgLinks
                })
            },
        });
    });
var orgItems = [
    {  
        "id":"110",
        "text":"ASP.NET\nTeam",
        "type": "ellipse"
    },
    {  
        "id":"112",
        "text":"Ken Samuelson",
        "type": "cardWithImageOnLeft",
        "picture": "images/employees/32.png"
    },
    {  
        "id":"113",
        "text":"Terry Bradley",
        "type": "cardWithImageOnLeft",
        "picture": "images/employees/33.png"
    },
];

var orgLinks = [  
    {  
        "id":"129",
        "from":"110",
        "to":"112",
    },
    {  
        "id":"130",
        "from":"110",
        "to":"113",
    }
];

Diagram - Data Binding Options

itemsExpr

Specifies the name of a data source field or an expression that returns a node's child items.

Type:

String

|

Function

Function parameters:
data: any

The current node's data object.

value: any

A node's child items or undefined.

Return Value: any

A node's child items.

Default Value: undefined

Specify this property when your source data has a hierarchical structure.

A function assigned to this property should do the following:

  • Return a node's child items when the value parameter is set to undefined.
  • Save item values to a data storage when the value parameter contains a node's child items. For instance, assign these values to the obj parameter's field to save a node's child items in your data source.

View Demo

index.js
data.js
$(function() {
    $("#diagram").dxDiagram({
        nodes: {
            dataSource: new DevExpress.data.ArrayStore({
                key: "this",
                data: employees
            }),
            textExpr: "Title",
            itemsExpr: "Items"
        },
    });
});
var employees = [{
    "Full_Name": "John Heart",
    "Title": "CEO",
    "Items": [{
        "Full_Name": "Arthur Miller",
        "Title": "CTO",
        "Items": [{
            "Full_Name": "Brett Wade",
            "Title": "IT Manager",
        }, {
            "Full_Name": "Barb Banks",
            "Title": "Support Manager",
        }]
    }, {
        "Full_Name": "Robert Reagan",
        "Title": "CMO",
        "Items": [{
            "Full_Name": "Ed Holmes",
            "Title": "Sales Manager",
        }]
    }]
}];

keyExpr

Specifies the name of a data source field or an expression that returns node keys.

Type:

String

|

Function

Function parameters:
data: any

The current node's data object.

value: any

A node's new key or undefined.

Return Value: any

A node key.

Default Value: 'id'

A function assigned to this property should do the following:

  • Return a node's new key when the value parameter is set to undefined.
  • Save a new key value to a data storage when the value parameter contains a node's key. For instance, assign this value to the obj parameter's field to save a node's key in your data source.

leftExpr

Specifies the name of a data source field or an expression that returns the x-coordinate of a node's left border.

Type:

String

|

Function

Function parameters:
data: any

The current node's data object.

value: any

The x-coordinate of a node's left border or undefined.

Return Value: any

The x-coordinate of a node's left border.

Default Value: undefined

A function assigned to this property should do the following:

  • Return the x-coordinate of a node's left border when the value parameter is set to undefined.
  • Save the x-coordinate value to a data storage when the value parameter contains the x-coordinate of a node's left border. For instance, assign this value to the obj parameter's field to save the x-coordinate of a node's left border in your data source.

A node's x-coordinate specifies the distance between the left border of a diagram work area and the left border of a shape, in units.

NOTE
Predefined shape coordinates are ignored when the autoLayout.type property is set to layered or tree.

lockedExpr

Specifies the name of a data source field or an expression whose Boolean value indicates whether a node is locked.

Type:

String

|

Function

Function parameters:
data: any

The current node's data object.

value: any

A Boolean value that indicates whether a node is locked or undefined.

Return Value: any

A Boolean value that indicates whether a node is locked.

Default Value: undefined

A function assigned to this property should do the following:

  • Return a Boolean value that indicates whether a node is locked when the value parameter is set to undefined.
  • Save a new value to a data storage when the value parameter contains a Boolean value. For instance, assign this value to the obj parameter's field to save a value that indicates whether a node is locked in your data source.

A locked item can not be moved, changed, or deleted. The context menu allows users to lock and unlock an item.

JavaScript
$(function() {
    $("#diagram").dxDiagram({
        nodes: {
            dataSource: new DevExpress.data.ArrayStore({
                key: "this",
                data: orgItems
            }),
            textExpr: "Title",
            parentKeyExpr: "Head_ID",
            lockedExpr: itemLockedExpr,
        },
    });
    function itemLockedExpr(obj, value) {
        if (value === "undefined")
            return obj.type === "group" ? "true" : "false";
        else
            obj.locked = value;
        return null;
    }
});

parentKeyExpr

Specifies the name of a data source field or an expression that returns a parent node key for a node.

Type:

String

|

Function

Function parameters:
data: any

The current node's data object.

value: any

A parent node key for a node or undefined.

Return Value: any

A parent node key for a node.

Default Value: undefined

A function assigned to this property should do the following:

  • Return a parent node key for a node when the value parameter is set to undefined.
  • Save a key value to a data storage when the value parameter contains a parent node key. For instance, assign this value to the obj parameter's field to save a parent node key for a node in your data source.

Specify this property if your source data has a linear structure.

View Demo

styleExpr

Specifies the name of a data source field or an expression that returns a node style.

Type:

String

|

Function

Function parameters:
data: any

The current node's data object.

value: any

A node's new style or undefined.

Return Value: any

A node style.

Default Value: undefined

A data source field assigned to this property should contain in-line style declarations in string format. For instance, "fill: #d9d9d9; stroke: #999999".

A function assigned to this property should do the following:

  • Return a node's new style as a set of CSS rules in JSON format when the value parameter is set to undefined. For instance, {"fill": "#d9d9d9"; "stroke": "#999999"}.
  • Save a new style value to a data storage when the value parameter contains a node's style. For instance, assign this value to the obj parameter's field to save a node's style in your data source.

index.js
$(function() {
    $("#diagram").dxDiagram({
        nodes: {
            styleExpr: itemStyleExpr,
        //...
    });

    function itemStyleExpr(obj) {
        let style = { "stroke": "#444444" };
        if(obj.type === "group")
            style["fill"] = "#f3f3f3";
        return style;
    }
});

View Demo

textExpr

Specifies the name of a data source field or an expression that returns node texts.

Type:

String

|

Function

Function parameters:
data: any

The current node's data object.

value: any

A node's new text or undefined.

Return Value: any

A node text.

Default Value: 'text'

A function assigned to this property should do the following:

  • Return a node's new text when the value parameter is set to undefined.
  • Save a new text value to a data storage when the value parameter contains a node's text. For instance, assign this value to the obj parameter's field to save a node's text in your data source.

textStyleExpr

Specifies the name of a data source field or an expression that returns a node's text style.

Type:

String

|

Function

Function parameters:
data: any

The current node's data object.

value: any

A node's new text style or undefined.

Return Value: any

A node's text style.

Default Value: undefined

A data source field assigned to this property should contain in-line style declarations in string format. For instance, "font-weight: bold; text-decoration: underline".

A function assigned to this property should do the following:

  • Return a node's text style as a set of CSS rules in JSON format when the value parameter is set to undefined. For instance, {"font-weight": "bold"; "text-decoration": "underline"}.
  • Save a new style value to a data storage when the value parameter contains a node's text style. For instance, assign this value to the obj parameter's field to save a node's text style in your data source.

index.js
$(function() {
    $("#diagram").dxDiagram({
        nodes: {
            textStyleExpr: itemTextStyleExpr,
        //...
    });

    function itemTextStyleExpr(obj, value) {
        if (value === "undefined") {
            let style = { "font-weight": "bold" };
            if(obj.level === "senior")
                style["text-decoration"] = "underline";
            return style;
        }
        else
            obj.style = value;
    }
});

View Demo

topExpr

Specifies the name of a data source field or an expression that returns the y-coordinate of a node's top border.

Type:

String

|

Function

Function parameters:
data: any

The current node's data object.

value: any

The y-coordinate of a node's top border or undefined.

Return Value: any

The y-coordinate of a node's top border.

Default Value: undefined

A function assigned to this property should do the following:

  • Return the y-coordinate of a node's top border when the value parameter is set to undefined.
  • Save the y-coordinate value to a data storage when the value parameter contains the y-coordinate of a node's top border. For instance, assign this value to the obj parameter's field to save the y-coordinate of a node's top in your data source.

A node's y-coordinate specifies the distance between the top border of a diagram work area and the top border of a shape, in units.

NOTE
Predefined shape coordinates are ignored when the autoLayout.type property is set to layered or tree.

typeExpr

Specifies the name of a data source field or an expression that returns the shape type for a node.

Type:

String

|

Function

Function parameters:
data: any

The current node's data object.

value: any

A node's new shape type or undefined.

Return Value: any

The shape type for a node.

Default Value: 'type'

A function assigned to this property should do the following:

  • Return a node's new shape type when the value parameter is set to undefined.
  • Save a new shape type value to a data storage when the value parameter contains a node's shape type. For instance, assign this value to the obj parameter's field to save a node's shape type in your data source.

The built-in shape types are shown in the Shape Types section.

JavaScript
$(function() {
    $("#diagram").dxDiagram({
        nodes: {
            typeExpr: itemTypeExpr,
            ...
        },
    });

    function itemTypeExpr(obj, value) {
        if(value)
            obj.type = (value === "rectangle") ? undefined : "group";
        else
            return obj.type === "group" ? "ellipse" : "rectangle";
    }
});

widthExpr

Specifies the name of a data source field or an expression that returns a node's width.

Type:

String

|

Function

Function parameters:
data: any

The current node's data object.

value: any

A node's new width or undefined.

Return Value: any

A node's width.

Default Value: undefined

A function assigned to this property should do the following:

  • Return a node's width when the value parameter is set to undefined.
  • Save a new width value to a data storage when the value parameter contains a node's width. For instance, assign this value to the obj parameter's field to save a node's width in your data source.

The units property specifies the measurement unit.

The example below demonstrates how to specify a node's width depending on the node's type:

jQuery
index.js
data.js
$(() => {
    $('#diagram').dxDiagram({
        nodes: {
            dataSource: new DevExpress.data.ArrayStore({
                key: 'id',
                data: orgItems,
            }),
            widthExpr: itemWidthExpr,
            // ...
        },
    });

    function itemWidthExpr(obj, value) {
        if (value === undefined)
            obj.width = value;
        else
            return obj.width || (obj.type === 'group' && 1.5) || 1;
        return null;
    }
});
const orgItems = [
    {
        id: '106',
        name: 'Development',
        type: 'group',
        width: 2,
    },
    {
        id: '112',
        name: 'Ana\nTrujillo',
        level: 'senior',
    },
    // ... 
];
Angular
app.component.html
app.module.ts
app.service.ts
<dx-diagram #diagram id="diagram">
    <dxo-nodes
        [dataSource]="orgItemsDataSource"
        keyExpr="ID"
        [widthExpr]="itemWidthExpr"
    >
    </dxo-nodes>
</dx-diagram>
import { DxDiagramModule, DxDiagramComponent } from 'devextreme-angular';
import ArrayStore from 'devextreme/data/array_store';
import { Service } from './app.service';

@Component({
    selector: 'app-root',
    templateUrl: 'app/app.component.html',
    styleUrls: ['app/app.component.css'],
    providers: [Service],
})

export class AppComponent {
    orgItemsDataSource: ArrayStore;

    constructor(service: Service) {
        this.orgItemsDataSource = new ArrayStore({
            key: 'ID',
            data: service.getOrgItems(),
        });
    }

    itemWidthExpr(obj, value) {
        if (value === undefined) 
            obj.Width = value;
        else 
            return obj.Width || (obj.Type === 'group' && 1.5) || 1;
    }
}
import { Injectable } from '@angular/core';

export class OrgItem {
    ID: string;
    Name: string;
    Type?: string;
    Level?: string;
    Width?: string;
}

const orgItems: OrgItem[] = [
    {
        ID: '106',
        Name: 'Development',
        Type: 'group',
        Width: '2',
    },
    {
        ID: '112',
        Name: 'Ana\nTrujillo',
        Level: 'senior',
    },
    // ...
];

@Injectable()
export class Service {
    getOrgItems() {
        return orgItems;
    }
}
Vue
App.vue
data.js
<template>
    <DxDiagram
        id="diagram"
        ref="diagram"
    >
        <DxNodes
            :data-source="orgItemsDataSource"
            :width-expr="itemWidthExpr"
        />
    </DxDiagram>
</template>
<script>
    import {
        DxDiagram, DxNodes,
    } from 'devextreme-vue/diagram';
    import ArrayStore from 'devextreme/data/array_store';
    import service from './data.js';

    export default {
        components: {
            DxDiagram, DxNodes
        },
        data() {
            return {
                orgItemsDataSource: new ArrayStore({
                    key: 'id',
                    data: service.getOrgItems(),
                }),
            };
        },
        methods: {
            itemWidthExpr(obj, value) {
                if (value === undefined)
                    obj.width = value;
                else
                    return obj.width || (obj.type === 'group' && 1.5) || 1;
                return null;
            },
        },
    };
</script>
const orgItems = [
    {
        id: '106',
        name: 'Development',
        type: 'group',
        width: '2'',
    },
    {
        id: '112',
        name: 'Ana\nTrujillo',
        level: 'senior',
    },
    // ...
];

export default {
    getOrgItems() {
        return orgItems;
    },
};
React
App.js
data.js
import React from 'react';
import Diagram, { Nodes } from 'devextreme-react/diagram';
import ArrayStore from 'devextreme/data/array_store';
import service from './data.js';

class App extends React.Component {
    constructor(props) {
        super(props);
        this.orgItemsDataSource = new ArrayStore({
            key: 'id',
            data: service.getOrgItems(),
        });
    }

    render() {
        return (
        <Diagram id="diagram">
            <Nodes dataSource={this.orgItemsDataSource}
                widthExpr={this.itemWidthExpr}
            />
        </Diagram>
        );
    }

    itemWidthExpr(obj, value) {
        if (value === undefined)
            obj.width = value;
        else
            return obj.width || (obj.type === 'group' && 1.5) || 1;
        return null;
    }
}

export default App;
const orgItems = [
    {
        id: '106',
        name: 'Development',
        type: 'group',
        width: '2',
    },
    {
        id: '112',
        name: 'Ana\nTrujillo',
        level: 'senior',
    },
    // ...
];

export default {
    getOrgItems() {
        return orgItems;
    },
};

View Demo

zIndexExpr

Specifies the name of a data source field or an expression that returns a node's z-index.

Type:

String

|

Function

Function parameters:
data: any

The current node's data object.

value: any

A node's new z-index or undefined.

Return Value: any

A node's z-index.

Default Value: undefined

A function assigned to this property should do the following:

  • Return a node's new z-index when the value parameter is set to undefined.
  • Save a new z-index value to a data storage when the value parameter contains a node's z-index. For instance, assign this value to the obj parameter's field to save a node's z-index in your data source.

The z-index specifies the node stack order. A node with greater stack order is in front of a node with a lower stack order.