Discover how to leverage the power of Angular’s mat-menu to create an interactive and seamless context menu experience. In this comprehensive guide, we will show you how to close an opened mat-menu and open it in a new location with a simple right-click. With easy-to-understand instructions and practical examples, you’ll have your context menu running smoothly in no time!
Understanding the Problem
Developers using Angular Material’s mat-menu to emulate a context menu often face a common issue. When they right-click on the page, the menu appears at the mouse location as expected. However, when moving the mouse to another location and right-clicking again, they expect the menu at the original location to close and reopen at the new location. Instead, the menu remains open at the original location, and nothing happens with the new right-click.
To close the opened menu at the original location and open it at a new mouse location, developers often have to left-click first, followed by a right-click. This can be cumbersome and unintuitive for users. So, how can we achieve the desired behavior?
Implementing the Solution
Let’s dive into the code to understand how to achieve the desired functionality. Below is the code for the HomeComponent class, which demonstrates how to create a context menu using mat-menu:
@Component({
selector: 'fl-home',
template:`
Clear all Paths
....
`})
export class HomeComponent {
menuX:number=0
menuY:number=0
@ViewChild(MatMenuTrigger,{static:false}) menu: MatMenuTrigger;
onTriggerContextMenu(event){
event.preventDefault();
this.menuX = event.x - 10;
this.menuY = event.y - 10;
this.menu.closeMenu() // close existing menu first.
this.menu.openMenu()
}
}
As you can see, the ‘onTriggerContextMenu’ function is responsible for closing the existing menu and opening a new one at the new mouse location. However, there’s a small issue that prevents this function from working as intended.
Introducing the ‘hasBackdrop’ Attribute
The issue lies in the backdrop overlay that appears when the menu is opened after a right-click. This invisible overlay covers the entire page, preventing the ‘contextmenu’ event from triggering and stopping ‘onTriggerContextMenu()’ from being called.
To fix this issue, simply add the ‘hasBackdrop’ attribute to the ‘mat-menu’ element and set its value to ‘false’:
By setting ‘hasBackdrop’ to ‘false’, the overlay will not appear, allowing the ‘contextmenu’ event to trigger as expected. However, this also means that the menu won’t close when clicking outside of it. To address this issue, you can implement a custom solution that listens for click events on the page and closes the menu accordingly.
