Restrict the drag and drop for particular tree nodes in Vue Treeview component

23 Dec 202419 minutes to read
You can restrict drag and drop operations to allow only dropping files under folders. This can be achieved by using the nodeDragStop and nodeDragging events of the TreeView.
Composition API (~/src/App.vue)
Options API (~/src/App.vue)
<template>
    <div id="app">
        <div class="control_wrapper">
            <ejs-treeview id='treeview' :fields="fields" :allowDragAndDrop='true' :nodeDragStop='dragStop'
                :nodeDragging='nodeDrag'></ejs-treeview>
        </div>
        <div id="display"></div>
    </div>
</template>
<script setup>

import { TreeViewComponent as EjsTreeview } from "@syncfusion/ej2-vue-navigations";

var dataSource = [
    {
        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' },
        ]
    },
];

const fields = { dataSource: dataSource, id: 'nodeId', text: 'nodeText', child: 'nodeChild', iconCss: 'icon', imageUrl: 'image' };

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

const dragStop = (args) => {
    if (args.droppedNode != null && args.droppedNode.getElementsByClassName('folder') && args.droppedNode.getElementsByClassName('folder').length === 0) {
        args.cancel = true;
    }
};

</script>
<style>
@import "../node_modules/@syncfusion/ej2-base/styles/material.css";
@import "../node_modules/@syncfusion/ej2-vue-navigations/styles/material.css";

.control_wrapper {
    display: block;
    max-width: 400px;
    max-height: 320px;
    margin: auto;
    overflow: auto;
    border: 1px solid #dddddd;
    border-radius: 3px;
}

.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>
<template>
    <div id="app">
        <div class="control_wrapper">
            <ejs-treeview id='treeview' :fields="fields" :allowDragAndDrop='true' :nodeDragStop='dragStop'
                :nodeDragging='nodeDrag'></ejs-treeview>
        </div>
        <div id="display"></div>
    </div>
</template>
<script>

import { TreeViewComponent } from "@syncfusion/ej2-vue-navigations";

export default {
    name: "App",
    components: {
        "ejs-treeview": TreeViewComponent
    },
    data() {
        var dataSource = [
            {
                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' },
                ]
            },
        ];
        return {
            fields: { dataSource: dataSource, id: 'nodeId', text: 'nodeText', child: 'nodeChild', iconCss: 'icon', imageUrl: 'image' },
        }
    },
    methods: {

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

        dragStop: function (args) {
            if (args.droppedNode != null && args.droppedNode.getElementsByClassName('folder') && args.droppedNode.getElementsByClassName('folder').length === 0) {
                args.cancel = true;
            }
        }
    }
}
</script>
<style>
@import "../node_modules/@syncfusion/ej2-base/styles/material.css";
@import "../node_modules/@syncfusion/ej2-vue-navigations/styles/material.css";

.control_wrapper {
    display: block;
    max-width: 400px;
    max-height: 320px;
    margin: auto;
    overflow: auto;
    border: 1px solid #dddddd;
    border-radius: 3px;
}

.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>