Angular2 call function from another component

Question

I have two components: NgbdAlertCloseable and AlertCtrl. Also I have AppComponent as parent component. What I want is to click a button in AlertCtrl component and create the alert on NgdbAlertCloseable component.

addSuccess() function adds an alert to the view and it worked well while I call it inside of its component. However, I tried to use an EventEmitter to call this function from another component (as suggested here: https://stackoverflow.com/a/37587862/5291422) but it gives this error:

ORIGINAL EXCEPTION: TypeError: self._NgbdAlertCloseable_2_4.addSuccess is not a function

Here are my files:

ngbd-alert-closeable.component.ts

import { Input, Component } from '@angular/core';

@Component({
  selector: 'ngbd-alert-closeable',
  templateUrl: './app/alert-closeable.html'
})
export class NgbdAlertCloseable {

  @Input()
  public alerts: Array<IAlert> = [];

  private backup: Array<IAlert>;

  private index: number; 

  constructor() {
    this.index = 1;
  }

  public closeAlert(alert: IAlert) {
    const index: number = this.alerts.indexOf(alert);
    this.alerts.splice(index, 1);
  }

  public static addSuccess(alert: IAlert) {
    this.alerts.push({
      id: this.index,
      type: 'success',
      message: 'This is an success alert',
    });
    this.index += 1;
  }

  public addInfo(alert: IAlert) {
    this.alerts.push({
      id: this.index,
      type: 'info',
      message: 'This is an info alert',
    });
    this.index += 1;
  }

}

interface IAlert {
  id: number;
  type: string;
  message: string;
}

alert-ctrl.component.ts

import { EventEmitter, Output, Component } from '@angular/core';
import { NgbdAlertCloseable } from './ngbd-alert-closeable.component';

@Component({
  selector: 'alert-ctrl',
  template: '<button class="btn btn-success" (click)="addSuccessMsg()">Add</button>'
})

export class AlertCtrl {
    @Output() msgEvent = new EventEmitter(); 
    public addSuccessMsg(){
        this.msgEvent.emit(null);
    }
}

app.component.ts

import { Component } from '@angular/core';

@Component({
  selector: 'my-app',
  template: '<div class="col-sm-4"><alert-ctrl (msgEvent)="ngbdalertcloseable.addSuccess()"></alert-ctrl><ngbd-alert-closeable #ngbdalertcloseable></ngbd-alert-closeable>'
})

export class AppComponent { }

Am I using it wrong? How can I fix that?

score 1 · Answer 1 · answered Oct 14 '16 at 01:16

Check that the addSuccess function is static and is using non static properties.

Should be:

 public addSuccess(alert: IAlert) {
    this.alerts.push({
      id: this.index,
      type: 'success',
      message: 'This is an success alert',
    });
    this.index += 1;
 }

And in your view you must pass the IAlert value in this example we'll send that value when we call msgEvent.emit(IAlert).

import { Component } from '@angular/core';

@Component({
  selector: 'my-app',
  template: '<div class="col-sm-4"><alert-ctrl (msgEvent)="ngbdalertcloseable.addSuccess($event)"></alert-ctrl><ngbd-alert-closeable #ngbdalertcloseable></ngbd-alert-closeable>'
})

export class AppComponent { }

Then you must send that IAlert, I'll change your AlertCtrl just for demo purpose.

import { EventEmitter, Output, Component } from '@angular/core';
import { NgbdAlertCloseable } from './ngbd-alert-closeable.component';

@Component({
  selector: 'alert-ctrl',
  template: '<button class="btn btn-success" (click)="addSuccessMsg()">Add</button>'
})

export class AlertCtrl {

    currentAlert:IAlert = {id: 0, type: 'success', message: 'This is an success alert'};

    @Output() msgEvent = new EventEmitter<IAlert>(); 
    public addSuccessMsg(){
        this.msgEvent.emit(this.currentAlert);
    }
}

Good luck and happy coding!

Angular2 call function from another component

1 Answers1