Search results

Customize treeview as accordion in Angular TreeView component

14 Apr 2021 / 2 minutes to read

Accordion is an interface where a list of items can be collapsed or expanded, but only one list can be collapsed or expanded at a time. You can customize the TreeView to make it behave as an accordion. Refer to the following code sample to create an accordion tree.

Source
Preview
app.component.ts
app.module.ts
main.ts
index.css
Copied to clipboard
import { Component, Inject, ViewChild } from '@angular/core';
import { TreeViewComponent, NodeSelectEventArgs } from '@syncfusion/ej2-angular-navigations';
/**
 * TreeView Accordion sample
 */
@Component({
    selector: 'app-container',
    template: `<div id='treeparent'><ejs-treeview id='treeElement' #treevalidate [fields]='field'  (nodeSelected)='nodeSelect($event)' [cssClass]='cssClass'></ejs-treeview></div>`
})
export class AppComponent {

   // Data source for TreeView component
   public continents: Object[] = [
       {
        code: "AF", name: "Africa", countries: [
            { code: "NGA", name: "Nigeria" },
            { code: "EGY", name: "Egypt" },
            { code: "ZAF", name: "South Africa" }
        ]
    },
    {
        code: "AS", name: "Asia", countries: [
            { code: "CHN", name: "China" },
            { code: "IND", name: "India", selected: true },
            { code: "JPN", name: "Japan" }
        ]
    },
    {
        code: "EU", name: "Europe", countries: [
            { code: "DNK", name: "Denmark" },
            { code: "FIN", name: "Finland" },
            { code: "AUT", name: "Austria",
             }
        ]
    },
    {
        code: "NA", name: "North America", countries: [
            { code: "USA", name: "United States of America" },
            { code: "CUB", name: "Cuba" },
            { code: "MEX", name: "Mexico" }
        ]
    },
    {
        code: "OC", name: "Oceania", countries: [
            { code: "AUS", name: "Australia" },
            { code: "NZL", name: "New Zealand" },
            { code: "WSM", name: "Samoa" }
        ]
    }
    ];
    public field:Object ={ dataSource: this.continents,  id: "code", text: "name", child: "countries" };
    public cssClass="accordiontree";

    @ViewChild ('treevalidate') tree: TreeViewComponent;

    public nodeSelect(args: NodeSelectEventArgs): void {
      if (args.node.classList.contains('e-level-1')) {
        this.tree.collapseAll();
        this.tree.expandAll([args.node]);
        this.tree.expandOn = 'none'
      }
    }
}
Copied to clipboard
import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { FormsModule } from '@angular/forms';
import { AppComponent } from './app.component';
import { TreeViewModule } from '@syncfusion/ej2-angular-navigations';
/**
 * Module
 */
@NgModule({
    imports: [
        BrowserModule,FormsModule, TreeViewModule
    ],
    declarations: [AppComponent],
    bootstrap: [AppComponent]
})
export class AppModule { }
Copied to clipboard
import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
import { enableProdMode } from '@angular/core';
import { AppModule } from './app.module';

enableProdMode();
platformBrowserDynamic().bootstrapModule(AppModule);
Copied to clipboard
#container {
    visibility: hidden;
}

#loader {
  color: #008cff;
  height: 40px;
  width: 30%;
  position: absolute;
  top: 45%;
  left: 45%;
}

#wrapper {
    width: 350px;
    margin: 0 auto;
}

#treeparent {
    display: block;
    max-width: 350px;
    max-height: 350px;
    margin: auto;
    overflow: auto;
}
.accordiontree .e-list-item.e-level-1 > .e-fullrow, .accordiontree .e-list-item.e-level-1.e-active > .e-fullrow,  .accordiontree .e-list-item.e-level-1.e-hover > .e-fullrow , .accordiontree .e-list-item.e-level-1 > .e-fullrow, .accordiontree .e-list-item.e-level-1.e-active.e-hover > .e-fullrow {
    background-color: darkslateblue;
    border-color: darkslateblue;
}

.accordiontree .e-list-item.e-level-1 > .e-text-content .e-list-text, .accordiontree .e-list-item.e-level-1.e-active > .e-text-content .e-list-text,  .accordiontree .e-list-item.e-level-1.e-hover > .e-text-content .e-list-text,  .accordiontree .e-list-item.e-level-1.e-active.e-hover > .e-text-content .e-list-text {
    color: white;
    font-size: 16px;
} 
.accordiontree .e-list-item.e-level- .e-icons.e-icon-collapsible, .accordiontree .e-list-item.e-level-1 .e-icons.e-icon-collapsible,.accordiontree .e-list-item.e-level-1 .e-icon-expandable {
    display: none
}

.accordiontree .e-list-item.e-level-2 > .e-fullrow, .accordiontree .e-list-item.e-level-2.e-active > .e-fullrow,  .accordiontree .e-list-item.e-level-2.e-hover > .e-fullrow , .accordiontree .e-list-item.e-level-2 > .e-fullrow, .accordiontree .e-list-item.e-level-2.e-active.e-hover > .e-fullrow {
    background-color: white;
    border-color: white;
}

.accordiontree .e-list-item.e-level-2 > .e-text-content .e-list-text, .accordiontree .e-list-item.e-level-2.e-active > .e-text-content .e-list-text,  .accordiontree .e-list-item.e-level-2.e-hover > .e-text-content .e-list-text,  .accordiontree .e-list-item.e-level-2.e-active.e-hover > .e-text-content .e-list-text {
    color: blue;
    font-size: 14px;
}