Change sub menu position in Angular Menu component

6 Sep 20224 minutes to read

The submenu position can be changed by using the beforeOpen event. Assign the top and left position where you want to open the submenu to the beforeOpen event arguments args.top and args.left respectively.

In the below sample, the sub menu opens above the parent menu item.

import { Component } from '@angular/core';
import { enableRipple, closest } from '@syncfusion/ej2-base';
import { MenuItemModel, BeforeOpenCloseMenuEventArgs } from '@syncfusion/ej2-angular-navigations';

enableRipple(true);

@Component({
    selector: 'app-root',
    template: `<!-- To Render Menu. -->
            <ejs-menu [items]='menuItems' (beforeOpen)='onBeforeOpen($event)'></ejs-menu>`
})

export class AppComponent {
    menuItems: MenuItemModel[] = [
    {
        text: 'File',
        items: [
            { text: 'Open' },
            { text: 'Save' },
            { text: 'Exit' }
        ]
    },
    {
        text: 'Edit',
        items: [
            { text: 'Cut' },
            { text: 'Copy' },
            { text: 'Paste' }
        ]
    },
    {
        text: 'View',
        items: [
            { text: 'Toolbar' },
            { text: 'Sidebar' }
        ]
    },
    {
        text: 'Tools',
        items: [
            { text: 'Spelling & Grammar' },
            { text: 'Customize' },
            { text: 'Options' }
        ]
    },
    { text: 'Go' },
    { text: 'Help' }];

    onBeforeOpen(args: BeforeOpenCloseMenuEventArgs): void {
        // Getting parent menu item element offset
        let relativeOffset: ClientRect = closest(args.event.target as Element, '.e-menu-item').getBoundingClientRect();
        // Getting sub menu wrapper element using closest method
        let subMenuEle: HTMLElement = closest(args.element, '.e-menu-wrapper') as HTMLElement;
        subMenuEle.style.display = 'block';
        args.top = (relativeOffset.top - subMenuEle.getBoundingClientRect().height) + pageYOffset;
        args.left = relativeOffset.left + pageXOffset;
        subMenuEle.style.display = '';
    }
}
import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { MenuModule } from '@syncfusion/ej2-angular-navigations';

import { AppComponent } from './app.component';

@NgModule({
    imports: [BrowserModule, MenuModule],
    declarations: [AppComponent],
    bootstrap: [AppComponent]
})
export class AppModule { }
import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
import { enableProdMode } from '@angular/core';
import { AppModule } from './app.module';

enableProdMode();
platformBrowserDynamic().bootstrapModule(AppModule);

For custom positioning, set both top and left position in the beforeOpen event.