Ionic button extension

I would like to extend the component ion-button

to add some methods to my own custom component. So I did:

import {Component, ElementRef, Renderer} from '@angular/core';
import {Button, Config} from "ionic-angular";

@Component({
  selector: '[search-button]',
  templateUrl: 'search-button.component.html',
})
export class SearchButtonComponent extends Button {
  constructor(ionButton: string, config: Config, elementRef: ElementRef, renderer: Renderer) {
    super(ionButton, config, elementRef, renderer);
  }
}

      

        
        
        
      

    

But this is giving me an error ERROR Error: Uncaught (in promise): Error: No provider for String!

.

What's a good way to expand ionic components?