Vue TreeList - Load Panel

The load panel is displayed while the UI component loads data. It consists of a loading indicator and text, both placed on a pane.

DevExtreme HTML5/JavaScript TreeList Widget - Load Panel

The load panel is shown only for remote data sources by default. To show it regardless of the data source type, assign true to the loadPanel.enabled property. Setting the same property to false disables the load panel completely.

jQuery
JavaScript
$(function() {
    $("#treeListContainer").dxTreeList({
        loadPanel: {
            enabled: true
        }
    });
});
Angular
HTML
TypeScript
<dx-tree-list ... >
    <dxo-load-panel
        [enabled]="true">
    </dxo-load-panel>
</dx-tree-list>
import { DxTreeListModule } from "devextreme-angular";
// ...
export class AppComponent {
    // ...
}
@NgModule({
    imports: [
        // ...
        DxTreeListModule
    ],
    // ...
})
Vue
App.vue
<template>
    <DxTreeList ... >
        <DxLoadPanel :enabled="true" />
    </DxTreeList>
</template>

<script>
import 'devextreme/dist/css/dx.light.css';

import DxTreeList, {
    DxLoadPanel
} from 'devextreme-vue/tree-list';

export default {
    components: {
        DxTreeList,
        DxLoadPanel
    },
    // ...
}
</script>
React
App.js
import React from 'react';
import 'devextreme/dist/css/dx.light.css';

import TreeList, {
    LoadPanel
} from 'devextreme-react/tree-list';

export default function App() {
    return (
        <TreeList ... >
            <LoadPanel enabled />
        </TreeList>
    );
}

You can also control the load panel programmatically using the beginCustomLoading(messageText) and endCustomLoading() methods.

jQuery
JavaScript
var treeList = $("#treeListContainer").dxTreeList("instance");
treeList.beginCustomLoading();
// ...
treeList.endCustomLoading();
Angular
TypeScript
import { ..., ViewChild } from "@angular/core";
import { DxTreeListModule, DxTreeListComponent } from "devextreme-angular";
// ...
export class AppComponent {
    @ViewChild(DxTreeListComponent, { static: false }) treeList: DxTreeListComponent;
    // Prior to Angular 8
    // @ViewChild(DxTreeListComponent) treeList: DxTreeListComponent;
    performLongOperation() {
        this.treeList.instance.beginCustomLoading();
        // ...
        this.treeList.instance.endCustomLoading();
    }
}
@NgModule({
    imports: [
        // ...
        DxTreeListModule
    ],
    // ...
})
Vue
App.vue
<template>
    <DxTreeList ref="treeListRefKey">
        <!-- ... -->
    </DxTreeList>
</template>

<script>
import 'devextreme/dist/css/dx.light.css';

import DxTreeList, {
    // ...
} from 'devextreme-vue/tree-list';

const treeListRefKey = "my-tree-list";

export default {
    components: {
        DxTreeList,
        // ...
    },
    data: function() {
        return {
            treeListRefKey
        };
    },
    methods: {
        performLongOperation: function() {
            this.treeList.beginCustomLoading();
            // ...
            this.treeList.endCustomLoading();
        }
    },
    computed: {
        treeList: function() {
            return this.$refs[treeListRefKey].instance;
        }
    }
}
</script>
React
App.js
import React, { useRef, useCallback } from 'react';
import 'devextreme/dist/css/dx.light.css';

import TreeList, {
    // ...
} from 'devextreme-react/tree-list';

export default function App() {
    const treeList = useRef(null);
    const performLongOperation = useCallback(() => {
        treeList.current.instance.beginCustomLoading();
        // ...
        treeList.current.instance.endCustomLoading();
    }, []);

    return (
        <TreeList ref="treeList">
            {/* ... */}
        </TreeList>
    );
}

Since the load panel is a DevExtreme LoadPanel UI component, you can declare any properties of this UI component in the TreeList's loadPanel object. For example, you can change the panel's size with the height and width properties, or employ another loading indicator using the indicatorSrc property.

jQuery
JavaScript
$(function() {
    $("#treeListContainer").dxTreeList({
        loadPanel: {
            height: 100,
            width: 250,
            indicatorSrc: "https://js.devexpress.com/Content/data/loadingIcons/rolling.svg"
        }
    });
});
Angular
HTML
TypeScript
<dx-tree-list ... >
    <dxo-load-panel
        [height]="100"
        [width]="250"
        indicatorSrc="https://js.devexpress.com/Content/data/loadingIcons/rolling.svg">
    </dxo-load-panel>
</dx-tree-list>
import { DxTreeListModule } from "devextreme-angular";
// ...
export class AppComponent {
    // ...
}
@NgModule({
    imports: [
        // ...
        DxTreeListModule
    ],
    // ...
})
Vue
App.vue
<template>
    <DxTreeList ... >
        <DxLoadPanel
            :height="100"
            :width="250"
            indicator-src="https://js.devexpress.com/Content/data/loadingIcons/rolling.svg"
        />
    </DxTreeList>
</template>

<script>
import 'devextreme/dist/css/dx.light.css';

import DxTreeList, {
    DxLoadPanel
} from 'devextreme-vue/tree-list';

export default {
    components: {
        DxTreeList,
        DxLoadPanel
    },
    // ...
}
</script>
React
App.js
import React from 'react';
import 'devextreme/dist/css/dx.light.css';

import TreeList, {
    LoadPanel
} from 'devextreme-react/tree-list';

export default function App() {
    return (
        <TreeList ... >
            <LoadPanel
                height={100}
                width={250}
                indicatorSrc="https://js.devexpress.com/Content/data/loadingIcons/rolling.svg"
            />
        </TreeList>
    );
}
See Also