Data source binding and custom menu items in Angular Menu component
27 Apr 202419 minutes to read
Data binding
The Menu supports data source bindings such as array of JavaScript objects
that can be structured as either hierarchical
or self-referential
data.
Hierarchical data
The Menu can be populated with hierarchical data source by assigning it to the items
property, and the fields with corresponding keys can be mapped to the fields
property.
JSON data
The Menu can generate its menu items through an array of complex data source by mapping fields from the fields
property.
import { NgModule } from '@angular/core'
import { BrowserModule } from '@angular/platform-browser'
import { MenuModule } from '@syncfusion/ej2-angular-navigations'
import { Component } from '@angular/core';
import { enableRipple } from '@syncfusion/ej2-base';
import { FieldSettingsModel } from '@syncfusion/ej2-angular-navigations';
// Import an array of JSON data from datasource.ts
import { dataSource } from './datasource';
enableRipple(true);
@Component({
imports: [ MenuModule],
standalone: true,
selector: 'app-root',
template: `<div class="e-section-control">
<ejs-menu [items]="data" [fields]='menuFields'></ejs-menu></div>`
})
export class AppComponent {
public menuFields: FieldSettingsModel = {
text: ['continent', 'country', 'language'],
children: ['countries', 'languages']
};
public data: { [key: string]: Object }[] = dataSource;
}
import { bootstrapApplication } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import 'zone.js';
bootstrapApplication(AppComponent).catch((err) => console.error(err));
Data Service
In application level, remote data binding can be achieved using DataManager
.
To create Menu, assign items property with resultant data from callback
function.
The following example displays five employees’ FirstName from Employees table and ShipName details from Orders table of the Northwind
Data Service.
import { NgModule } from '@angular/core'
import { BrowserModule } from '@angular/platform-browser'
import { MenuModule } from '@syncfusion/ej2-angular-navigations'
import { Component, OnInit } from '@angular/core';
import { enableRipple } from '@syncfusion/ej2-base';
import { DataManager, Query, ODataV4Adaptor, ReturnOption } from '@syncfusion/ej2-data';
import { FieldSettingsModel } from '@syncfusion/ej2-angular-navigations';
enableRipple(true);
@Component({
imports: [ MenuModule],
standalone: true,
selector: 'app-root',
template: `<div class="e-section-control">
<ejs-menu *ngIf='menuItems' [items]='menuItems' [fields]='menuFields'></ejs-menu></div>`
})
export class AppComponent implements OnInit {
private SERVICE_URI: string = 'https://services.odata.org/V4/Northwind/Northwind.svc/';
// Menu fields definition.
public menuFields: FieldSettingsModel = {
text: ['FirstName', 'ShipName'],
children: ['Orders']
};
public menuItems?: { [key: string]: Object }[];
public ngOnInit(): void {
// Getting remote data using DataManager.
new DataManager({ url: this.SERVICE_URI, adaptor: new ODataV4Adaptor(), crossDomain: true })
.executeQuery(
new Query().from('Employees').take(5).hierarchy(
new Query()
.foreignKey('EmployeeID')
.from('Orders').take(13),
function () {
return [1, 2, 3, 4, 5]
}
))
.then((e: ReturnOption) => {
//Assign result data to menu items
this.menuItems = e.result as { [key: string]: Object }[];
const loaderElement = document.getElementById('loader') as HTMLElement;
if (loaderElement) {
loaderElement.style.display = "none";
}
});
}
}
import { bootstrapApplication } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import 'zone.js';
bootstrapApplication(AppComponent).catch((err) => console.error(err));
Self-referential data
Menu can be populated from self-referential data structure that contains array of JSON objects with parentId
mapping.
You can directly assign self-referential data to the items
property, and map all the field members with corresponding keys from self-referential data to fields property.
To render the root level nodes, specify the parentId
as null or no need to specify the parentId
in data source.
In the following example, the id, pId, and text columns from self-referential data have been mapped to the itemId
, parentId
, and text
fields, respectively.
import { NgModule } from '@angular/core'
import { BrowserModule } from '@angular/platform-browser'
import { MenuModule } from '@syncfusion/ej2-angular-navigations'
import { Component } from '@angular/core';
import { enableRipple } from '@syncfusion/ej2-base';
import { FieldSettingsModel } from '@syncfusion/ej2-angular-navigations';
enableRipple(true);
@Component({
imports: [ MenuModule],
standalone: true,
selector: 'app-root',
template: `<div class="e-section-control">
<ejs-menu [items]='data' [fields]='menuFields'></ejs-menu>
</div>`
})
export class AppComponent {
//Menu datasource
public data: { [key: string]: Object }[] = [
{ id: 'parent1', text: 'Events' },
{ id: 'parent2', text: 'Movies' },
{ id: 'parent3', text: 'Directory' },
{ id: 'parent4', text: 'Queries', pId: null as any },
{ id: 'parent5', text: 'Services', pId: null as any },
{ id: 'parent6', text: 'Conferences', pId: 'parent1' },
{ id: 'parent7', text: 'Music', pId: 'parent1' },
{ id: 'parent8', text: 'Workshops', pId: 'parent1' },
{ id: 'parent9', text: 'Now Showing', pId: 'parent2' },
{ id: 'parent10', text: 'Coming Soon', pId: 'parent2' },
{ id: 'parent10', text: 'Media Gallery', pId: 'parent3' },
{ id: 'parent11', text: 'Newsletters', pId: 'parent3' },
{ id: 'parent12', text: 'Our Policy', pId: 'parent4' },
{ id: 'parent13', text: 'Site Map', pId: 'parent4' },
{ id: 'parent14', text: 'Pop', pId: 'parent7' },
{ id: 'parent15', text: 'Folk', pId: 'parent7' },
{ id: 'parent16', text: 'Classical', pId: 'parent7' }
];
//Menu fields definition
public menuFields: FieldSettingsModel = {
itemId: 'id',
text: 'text',
parentId: 'pId'
};
}
import { bootstrapApplication } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import 'zone.js';
bootstrapApplication(AppComponent).catch((err) => console.error(err));
Custom menu items
The Menu can be customized using Essential JS2 Template engine to render the elements.
To customize menu items in your application, set your customized template string to the template
property.
In the following example, the menu has been rendered with customized menu items.
import { NgModule } from '@angular/core'
import { BrowserModule } from '@angular/platform-browser'
import { MenuModule } from '@syncfusion/ej2-angular-navigations'
import { ButtonModule } from '@syncfusion/ej2-angular-buttons'
import { Component, Inject } from '@angular/core';
import { FieldSettingsModel } from '@syncfusion/ej2-angular-navigations';
import { enableRipple } from '@syncfusion/ej2-base';
enableRipple(false);
@Component({
imports: [ MenuModule, ButtonModule],
providers: [
{ provide: 'sourceFiles', useValue: {files: []
standalone: true,
selector: 'app-root',
styleUrls: ['./template.css'],
template: `<div class="e-section-control">
<div id="menuTemplate" class="menu-section">
<div class="menu-control">
<ejs-menu [items]='dataSource' [fields]='menuFields' [animationSettings]="animation" cssClass="e-template-menu">
<ng-template #template let-dataSource="">
<div *ngIf="dataSource.value" style="width:100%;display:flex;justify-content:space-between;">
<img *ngIf="dataSource.url" class="e-avatar e-avatar-small"
src="src/images/platforms/.png" />
<span style="width:100%;"></span>
<span *ngIf="dataSource.count" class='e-badge e-badge-success'></span>
</div>
<div *ngIf="dataSource.about" tabindex="0" class="e-card">
<div class="e-card-header">
<div class="e-card-header-caption">
<div class="e-card-header-title">About Us</div>
</div>
</div>
<div class="e-card-content">
</div>
<div class="e-card-actions">
<button class="e-btn e-outline" style="pointer-events: auto;">
Read More
</button>
</div>
</div>
</ng-template>
</ejs-menu>
</div>
</div>
</div>`
})
export class AppComponent {
animation: any;
constructor(@Inject('sourceFiles') public sourceFiles: any) {
sourceFiles.files = ['template.css'];
}
//Template datasource
public dataSource: { [key: string]: Object }[] = [
{
category: 'Products',
options: [
{ value: 'JavaScript', url: 'https://ej2.syncfusion.com/angular/documentation/../../../../../menu/images/javascript' },
{ value: 'Angular', url: '../../../../../../menu/images/angular' },
{ value: 'ASP.NET Core', url: '../../../../../../menu/images/core' },
{ value: 'ASP.NET MVC', url: '../../../../../../menu/images/mvc' }
]
},
{
category: 'Services',
options: [
{ value: 'Application Development', count: '1200+' },
{ value: 'Maintenance & Support', count: '3700+' },
{ value: 'Quality Assurance' },
{ value: 'Cloud Integration', count: '900+' }
]
},
{
category: 'About Us',
options: [
{
id: 'about',
about: {
value: "We are on a mission to provide world-class best software solutions for web, mobile and desktop platforms. Around 900+ applications are desgined and delivered to our customers to make digital & strengthen their businesses."
}
}
]
},
{ category: 'Careers' },
{ category: 'Sign In' }
];
// Menu fields definition
public menuFields: object = {
text: ['category', 'value'],
children: ['options']
};
}
import { bootstrapApplication } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import 'zone.js';
bootstrapApplication(AppComponent).catch((err) => console.error(err));
To prevent sub menu closing, set
args.cancel
totrue
inbeforeClose
event.