Angular Component Ref

AngularJS is what HTML would have been had it been designed for building web-apps. We have seen the file structure in one of our previous chapters.

Here S What You Should Know When Creating Flexible And Reusable Components In Angular Angular Indepth

Without the ngForm attribute value the reference value of itemForm would be the HTMLFormElement.

Angular component ref. In the code below a template reference variable is created that references the with id test-div. It is based on Tailwind Starter Kit by Creative Tim and it is build with both presentation pages and pages for an admin dashboard. To create a template reference variable locate the HTML element that you want to reference and then tag it like so.

There may be situations where you want to access a directive child component or a DOM element from a parent component class. There is however a difference between a Component and a Directive in that Angular references a Component without specifying the attribute value and a Directive does not change the implicit reference or the element. If we pass objects in the Input decorator then it would be passed as a reference and if we pass primitive types then it would be passed as a value.

It can contain a reference to elements like h1 div etc. The file structure has the app component and it consists of the following files. The reference variable itemNameInput declares a itemNameInput variable on an element.

We can also pass it to a method in the component. It features multiple HTML and Angular elements and it comes with dynamic components for Angular. The ViewChild decorator returns the first element that matches a given directive component or template reference selector.

Its simply a class that wraps native DOM elements in the browser and allows you to work with the DOM by providing the nativeElement object which exposes all the methods and properties of the native elements. Angular ElementRef is a wrapper around a native element inside of a View. Notus Angular is Free and Open Source.

We can summarize this as follows. Private attachChildComponent childComponent. The Template reference variable is a reference to any DOM element component or a directive in the Template.

ViewContainerRef const componentFactory. In the component use it with ViewChild it will be available OnInit. Angular Access template reference variables from component class.

Declarative templates with data-binding MVC dependency injection and great testability story all implemented with pure client-side JavaScript. ViewContainerRef when injected to via DI holds the reference to the host element that hosts the component or directive. This article will introduce you to Angulars ViewChild decorator.

Start typing in the live Stackblitz demo to see the model reflect as we type note were using the username reference exports the reference to the DOM Node. As username is now a reference variable bound to the Angular component we can access it anywhere - which is exactly what Im doing with usernamevalue and logging out the value. Using ViewChild with Directives.

ComponentRef provides access to the Component Instance as well other objects related to this Component Instance and allows you to destroy the Component Instance via the destroy method. That gives you a reference to the child component and the ability to access any of its properties or methods from within the parent template. Major part of the development with Angular 4 is done in the components.

The parent component cannot data bind to the childs start and stop methods nor to its seconds property. Represents an instance of a Component created via a ComponentFactory. When you dynamically create a component using the ViewContainerRefcreateComponent method if the Child Component has changeDetection.

You can place a local variable timer on the tag representing the child component. My-componenthtml export class MyComponent implements OnInit ViewChildtemplateref public templateref. ChangeDetectionStrategyOnPush the Child Component content lifecycle is not triggered.

Alternatively you can take a look at Renderer2 which provides API that can safely be used even when direct access to native elements is. We can use it elsewhere in the template. To declare a reference variable in a template you need to use hash symbol as shown below.

Use templating and data-binding provided by Angular instead. To get started using template reference variables simply create a new Angular component or visit an existing one. Components are basically classes that interact with thehtml file of the component which gets displayed on the browser.

Once we have ViewContainerRef we can use the createEmbeddedView method to add the template to the component. Speed up your web development with a beautiful product made by Creative Tim.

Dynamically Creating Components With Angular By Netanel Basal Netanel Basal