Calling function in Directive

Ionic Framework ionic-v3
1

Hey,
How can I call a function (defined in my HomePage) in a directive?

This is my directive :

import [...]
import { BattlePage } from '../../pages/battle/battle';

@Directive({
  selector: '[absolute-drag]'
})
export class AbsoluteDrag {
    constructor(...) { }

    handlePan(){
        [...]
        // Where I want to call the function
    }
}

This is my Home script :

import { Component, ViewChild, trigger, transition, state, style, animate, keyframes } from '@angular/core';
import { IonicPage, NavController, NavParams } from 'ionic-angular';

@IonicPage()
export class BattlePage {
  constructor(public navCtrl: NavController, public navParams: NavParams) {}

  // The function I want to call
  rollDice( ) { ... }
}

Thank you!