Restrict the drag and drop for particular tree nodes in EJ2 TypeScript Treeview control

2 May 202312 minutes to read

You can able to restrict to drag and drop files under folder only. These can be achieved by using ‘nodeDragStop’ and ‘nodeDragging’ event of TreeView.

import { enableRipple } from '@syncfusion/ej2-base';
import { TreeView } from '@syncfusion/ej2-navigations';
enableRipple(true);

    // Hierarchical data source for TreeView component
    let hierarchicalData: { [key: string]: Object }[] = [
        {
            nodeId: '01', nodeText: 'Music', icon: 'folder',
            nodeChild: [
                { nodeId: '01-01', nodeText: 'Gouttes.mp3', icon: 'audio' }
            ]
        },
        {
            nodeId: '02', nodeText: 'Videos', icon: 'folder',
            nodeChild: [
                { nodeId: '02-01', nodeText: 'Naturals.mp4', icon: 'video' },
                { nodeId: '02-02', nodeText: 'Wild.mpeg', icon: 'video' },
            ]
        },
        {
            nodeId: '03', nodeText: 'Documents', icon: 'folder',
            nodeChild: [
                { nodeId: '03-01', nodeText: 'Environment Pollution.docx', icon: 'docx' },
                { nodeId: '03-02', nodeText: 'Global Water, Sanitation, & Hygiene.docx', icon: 'docx' },
                { nodeId: '03-03', nodeText: 'Global Warming.ppt', icon: 'ppt' },
                { nodeId: '03-04', nodeText: 'Social Network.pdf', icon: 'pdf' },
                { nodeId: '03-05', nodeText: 'Youth Empowerment.pdf', icon: 'pdf' },
            ]
        },
        {
            nodeId: '04', nodeText: 'Pictures', icon: 'folder', expanded: true,
            nodeChild: [
                {
                    nodeId: '04-01', nodeText: 'Camera Roll', icon: 'folder', expanded: true,
                    nodeChild: [
                        { nodeId: '04-01-01', nodeText: 'WIN_20160726_094117.JPG', image: 'https://ej2.syncfusion.com/demos/src/treeview/images/employees/9.png' },
                        { nodeId: '04-01-02', nodeText: 'WIN_20160726_094118.JPG', image: 'https://ej2.syncfusion.com/demos/src/treeview/images/employees/3.png' },
                    ]
                },
                { nodeId: '04-02', nodeText: 'Wind.jpg', icon: 'images' },
                { nodeId: '04-03', nodeText: 'Stone.jpg', icon: 'images' },
            ]
        },
        {
            nodeId: '05', nodeText: 'Downloads', icon: 'folder',
            nodeChild: [
                { nodeId: '05-01', nodeText: 'UI-Guide.pdf', icon: 'pdf' },
                { nodeId: '05-02', nodeText: 'Tutorials.zip', icon: 'zip' },
                { nodeId: '05-03', nodeText: 'Game.exe', icon: 'exe' },
                { nodeId: '05-04', nodeText: 'TypeScript.7z', icon: 'zip' },
            ]
        },
    ];

    // Render the TreeView with image icons
    let treeObj: TreeView = new TreeView({
        fields: { dataSource: hierarchicalData, id: 'nodeId', text: 'nodeText', child: 'nodeChild', iconCss: 'icon', imageUrl: 'image' },
        sortOrder: 'Ascending',
        allowDragAndDrop: true,
        nodeDragStop: dragStop,
        nodeDragging: nodeDrag
    });
    treeObj.appendTo('#tree');

function nodeDrag(args: DragAndDropEventArgs): void {
    if (args.droppedNode != null && args.droppedNode.getElementsByClassName('folder') && args.droppedNode.getElementsByClassName('folder').length === 0)      {
        args.dropIndicator = 'e-no-drop';
    }
}

function dragStop(args: DragAndDropEventArgs): void {
    if (args.droppedNode != null && args.droppedNode.getElementsByClassName('folder') && args.droppedNode.getElementsByClassName('folder').length === 0) {
        args.cancel = true;
    }
}
<!DOCTYPE html>
<html lang="en">

<head>
    <title>Essential JS 2 for TreeView </title>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <meta name="description" content="Essential JS 2 for TreeView UI Control" />
    <meta name="author" content="Syncfusion" />
    <link href="index.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/24.2.3/ej2-base/styles/material.css" rel="stylesheet" />
    <link href="https://cdn.syncfusion.com/ej2/24.2.3/ej2-navigations/styles/material.css" rel="stylesheet" />
    <script src="https://cdnjs.cloudflare.com/ajax/libs/systemjs/0.19.38/system.js"></script>
    <script src="systemjs.config.js"></script>
<script src="https://cdn.syncfusion.com/ej2/syncfusion-helper.js" type ="text/javascript"></script>
</head>

<body>
    <div id='loader'>Loading....</div>
    <div id='container'>
        <div id='treeparent'>
            <div id="tree"></div>
        </div>
    </div>
    <style>
        .e-treeview .e-list-img {
            width: 25px;
            height: 25px;
        }

        /* Loading sprite image for TreeView */
        .e-treeview .e-list-icon {
            background-repeat: no-repeat;
            background-image: url(https://ej2.syncfusion.com/demos/src/treeview/images/icons/file_icons.png);
            height: 20px;
        }

            /* Specify the icon positions based upon class name */
            .e-treeview .e-list-icon.folder {
                background-position: -10px -552px;
            }

            .e-treeview .e-list-icon.docx {
                background-position: -10px -20px;
            }

            .e-treeview .e-list-icon.ppt {
                background-position: -10px -48px;
            }

            .e-treeview .e-list-icon.pdf {
                background-position: -10px -104px;
            }

            .e-treeview .e-list-icon.images {
                background-position: -10px -132px;
            }

            .e-treeview .e-list-icon.zip {
                background-position: -10px -188px;
            }

            .e-treeview .e-list-icon.audio {
                background-position: -10px -244px;
            }

            .e-treeview .e-list-icon.video {
                background-position: -10px -272px;
            }

            .e-treeview .e-list-icon.exe {
                background-position: -10px -412px;
            }
    </style>
</body>

</html>