Executing a function within an Angular 2/4 component

When attempting to use a method of a component in another, I encountered an error message stating "No provider for xxComponent". How can this be resolved?

import { FoldersService } from '../../_services/folders.service';
import { Component, OnInit, ViewChild } from '@angular/core';

@Component({
  selector: 'app-folder-create',
  templateUrl: './folder-create.component.html',
})
export class FolderCreateComponent implements OnInit {
   constructor(
    private http: Http,
    private folderService: FoldersService,
  ) { }

  ngOnInit() { }

  saveFolder() {

  }
}

-- Class FolderEditComponent 
   import { FolderCreateComponent } from '../folder-create/folder-create.component';
@Component({
  selector: 'app-folder-edit',
  templateUrl: './folder-edit.component.html',
  styleUrls: ['./folder-edit.component.css'],
})
export class FolderEditComponent implements OnInit {
   constructor(
    private http: Http,
    private folderService: FoldersService,
    private folderCreate: FolderCreateComponent
  ) { }

  ngOnInit() { }

  // How can I call the saveFolder() method of the FolderCreateComponent component here?

  // Attempted solution:
  folderCreate.saveFolder(); // Resulted in error: ERROR Error: Uncaught (in promise): Error: No provider for FolderCreateComponent!

}

What is the correct way to call the saveFolder() method of the FolderCreateComponent component within the FolderEditComponent component?

Answer №1

Scenario 1 - If you need to call a method of a child component from the parent component, follow these steps:

@ViewChild(ChildComponent) childComponent: ChildComponent;

childComponent.methodName();

Scenario 2 - If you want to call a method of the parent component from within a child component:

In the constructor of the child component, use dependency injection as shown below:

constructor(@Inject(forwardRef(() => ParentComponent)) private _parent: ParentComponent){}

Then simply call the parent method using this._parent.methodName().

Answer №2

Include the necessary Providers for FolderCreateComponent

import { FoldersService } from '../../_services/folders.service';
import { Component, OnInit, ViewChild } from '@angular/core';
import { Http, Response } from '@angular/http';

@Component({
  selector: 'app-folder-create',
  templateUrl: './folder-create.component.html',
  providers: [FoldersService]
})
export class FolderCreateComponent implements OnInit {
   constructor(
    private http: Http,
    private folderService: FoldersService,
  ) { }

  ngOnInit() { }

  saveFolder() {

  }
}

Answer №3

Ensure that you include your service as one of the used providers in your component:

@Component({
  selector: 'app-directory-add',
  templateUrl: './directory-add.component.html',
  providers: [DirectoryService]
})

Furthermore, make sure to import the necessary component using

import {BarComponent} from '/path/to/bar.component';
so that you can utilize a component within another.

Update:

import {DirectoryAddComponent} from 'path/to/component';

export class DirectoryEditComponent implements OnInit {

   constructor(private directoryAdd: DirectoryAddComponent) {
   }

   bar() { this.directoryAdd.saveDirectory(); }
}

Similar questions

If you have not found the answer to your question or you are interested in this topic, then look at other similar questions below or use the search

What are the steps to effectively troubleshoot TypeScript code in Visual Studio 2017?

Currently working on an ASP.NET Core project that heavily utilizes TypeScript. Does Visual Studio support debugging TypeScript code? ...

When I apply flex to the display of .ant-steps-item-icon, the connection between the steps vanishes

I recently utilized ANTD and React to develop a customized component step style, but ran into an issue. Here is the CSS code snippet I used: /* step connector */ .ant-steps-item-title:after { border: solid rgba(65, 64, 66, 0.1) !important; } /* step * ...

Assigning the identical function to multiple buttons in Ionic version 2

I designed an eye icon button for toggling password visibility. However, I have a specific page that needs to serve as the "password recovery" page. In this particular page, there are 3 input fields, each with the same toggle button attached to them... ...

Unable to initiate a new project in Node.js

As I was working on adding a new project in Angular, everything was running smoothly until today. However, when trying to create a new project today, I noticed that the node_modules folder is missing and encountered the following errors: https://i.stack.i ...

Steps to prevent subfolder imports in my npm package

My npm package is built using: typescript webpack webpack.config: {... entry: './src/index.ts } library tree: - package.json - src - - index.ts - - ...all_my_code... I have all my library functionality and types exported from the index.ts file. T ...

Which is more suitable to implement in Angular 2: <page type="list"> or <listpage>?

As I embark on my journey with Angular2, my goal is to develop a dynamic todo-list web application. The user interface will consist of two pages, or components, that slide in and out using JavaScript. The first page will display all the todos in a vertica ...

What are the drawbacks of introducing a dependency within the constructor?

I'm struggling to understand why breaking the rules is considered bad. import {DepClass} from './di-import' // <- some dependency imports here class DI1 { dep1: DepClass constructor(){ this.dep1 = new DepClass() // ...

"Sending the selected pass selector as a parameter to the dispatched action is causing a typing

When a selector changes its value, I want to trigger an action. To achieve this, I passed the selector with a subscription instead of passing an observable. selectedSchedulingsOnPopup$ = this.store.pipe(select(selectSchedulingsByBranch)); this.store.disp ...

Creating a Higher Order Component with TypeScript using React's useContext API

Looking to convert this .js code snippet into Typescript. import React from 'react'; const FirebaseContext = React.createContext(null) export const withFirebase = Component => props => ( <FirebaseContext.Consumer> {fire ...

What is the best way to deactivate an <a> tag in React after it has been clicked?

Is there a way to deactivate the anchor tag below in React once it has been clicked? The onClick function is not functioning on the anchor tag. <td align="left"> <input type="file" accept=".csv,.xlsx,.xls" ...

Using Typescript (Angular) for consistent md5 hashing

Attempting to generate an identifier that is produced in the back-end, on the front-end (not the most recommended practice, I understand). The identifier is formed by an Md5 hash of multiple strings concatenated together dynamically. In order to achieve th ...

Inform the component of an error detected in the Angular service

In Angular versions prior to 8, it was possible to subscribe to both success and error Observables from the component object. This allowed the component to perform one action if the service operation completed successfully, and a different action if ther ...

Console.log is displaying array as [object Object] when utilizing Typescript

When working with an object in typescript called "obj," I encountered a strange behavior. Initially, when I ran the console.log(obj); command, the output in the terminal console was displayed as [object Object]. However, after wrapping it in JSON.stringify ...

What is causing the "excessive stack depth" error in this JSX code?

Exploring Next.js' TypeScript (4.2.3) functionality, I am utilizing it to compile the React component provided below. const Component = (): JSX.Element => { const categories = ['Fruit', 'Vegetables']; return ( <ul> ...

Having trouble declaring custom pipes in Angular

A new pipe named 'shortend.pipe.ts' has been created within the app folder. import { PipeTransform } from "@angular/core"; export class ShortendPipe implements PipeTransform { transform(value: any, ...args: any[]) { return ...

Implementing serialization and deserialization functionality in Typescript for classes containing nested maps

I am currently facing a challenge in transforming Typescript code into NodeJS, specifically dealing with classes that contain Map fields of objects. I have been experimenting with the class-transformer package for serialization and deserialization (to JSON ...

Steps for exporting various elements from a .vue file

In my Vue project, I am incorporating TypeScript along with Vue. There is a specific scenario where I need to export multiple items from my .vue file. Here's an example of what I want to achieve: // FooBar.vue <template> ... </template& ...

NextJS: Build error - TypeScript package not detected

I'm facing an issue while setting up my NextJS application in TypeScript on my hosting server. On my local machine, everything works fine when I run next build. However, on the server, I'm encountering this error: > next build It seems that T ...

Issue encountered while running the 'yarn install' command in a React project: 'The system does not recognize the term 'yarn'

When attempting to run the 'yarn install' command in my React project, I'm running into a problem. Even though I have Yarn installed globally (npm install --global yarn), I keep getting an error when trying to use any Yarn command in the ter ...

Utilizing TypeScript to parse a JSON document

As a complete beginner in learning TypeScript, I am exploring how to parse JSON data on a web page and understand the underlying process. Despite searching extensively online, I have yet to find a solution. Here is my current code: var a = fetch("places ...