Styjun

Is there a way to change the OverlayContainer?

I have created a tooltip component, but sometimes I want to attach the overlay to a specific element (by default the overlay is attached to the document body).

Here is how I am creating the overlay:

 private initOverlay(): void 
 const positionStrategy = this.overlayPositionBuilder
 .flexibleConnectedTo(this.elementRef)
 .withPositions([this.resolvedConfig]);

 this.overlayRef = this.overlay.create(positionStrategy);
 

And this is how I am attaching a template to it:

 show(): void 
 this.overlayRef.attach(new TemplatePortal(this.tpl, this.viewContainerRef));
 

Please reference this stackblitz example.

looks like you can accomplish this by extending the
OverlayContainer class via the following in app.module.ts

provide: OverlayContainer, useFactory: () => new AppOverlayContainer()

Stackblitz

https://stackblitz.com/edit/angular-material2-issue-ansnt5?file=app%2Fapp.module.ts

This GitHub comment also provides an example of how to package this in a directive

GitHub comment

https://github.com/angular/material2/issues/7349#issuecomment-337513040

Revision 3/22/19 working directive example

Extend the OverlayContainer class via cdk-overlay-container.ts

Stub the class in app.module.ts

 providers: [
 provide: OverlayContainer, useClass: CdkOverlayContainer ,
 ]

In your cdk-overlay-container.ts you are preventing the default _createContainer() from working, and providing your own custom public method myCreateContainer to replace it.

You are essentially creating an empty div here, adding a custom class to it my-custom-overlay-container-class and appending it to the
div the directive is attached to, then passing that container to the
private variable _containerElement in the true OverlayContainer
class.

/**
* Create overlay container and append to ElementRef from directive
*/ 
public myCreateContainer(element: HTMLElement): void 
 let container = document.createElement('div');
 container.classList.add('my-custom-overlay-container-class');

 element.appendChild(container);
 this._containerElement = container;
 
 /**
 * Prevent creation of the HTML element, use custom method above
 */
 protected _createContainer(): void 
 return;
 

Then in your cdk-overlay-container.directive.ts your are calling myCreateContainer() and passing the ElementRef as an argument.

 this.cdkOverlayContainer['myCreateContainer'](this.elementReference.nativeElement);

Then in your HTML assign the directive where you want it to show up.

<div myCdkOverlayContainer 

Stackblitz

https://stackblitz.com/edit/angular-material2-issue-6nzwws?embed=1&file=app/app.component.html