How to access the child component from parent component with View Child Angular ? 96

 How to access the child component from parent component with View Child Angular ?

Here's a detailed response explaining how to access a child component from a parent component using ViewChild in Angular:

Steps:

1. Import necessary modules:
   Import the ViewChild decorator and the component type of your child component in your parent component's TypeScript file.
   TypeScript
   import { Component, ViewChild } from '@angular/core';
   import { MyChildComponent } from './my-child.component';
   
   

2. Declare a template reference variable:
   In your parent component's template, add a reference variable using the # symbol to the element representing the child component.
   HTML
   <app-my-child #childComponent></app-my-child>
   
   

3. Use @ViewChild decorator:
   In your parent component's TypeScript class, decorate a property with @ViewChild() and associate it with the reference variable name from step 2. Specify the child component type as the template.
   TypeScript
   @ViewChild('childComponent') childComponent: MyChildComponent;
   
   

4. Access the child component:
   Once the view has been initialized (usually inside lifecycle hooks like ngAfterViewInit), you can access the child component instance through the childComponent property and call its methods or access its properties.
   TypeScript
   ngAfterViewInit() {
     this.childComponent.someMethod(); // Call method on child component
     console.log(this.childComponent.someProperty); // Access property of child component
   }
   
   

Example:

Let's say you have a parent component ParentComponent and a child component MyChildComponent. You want to call a method incrementCounter on the child component from the parent.

HTML

<app-my-child #childComponent></app-my-child>

@Component({ /* ... */ })
export class ParentComponent {
  @ViewChild('childComponent') childComponent: MyChildComponent;

  ngAfterViewInit() {
    this.childComponent.incrementCounter();
  }
}

@Component({ /* ... */ })
export class MyChildComponent {
  counter = 0;

  incrementCounter() {
    this.counter++;
  }
}

Additional considerations:

• Accessing the child component before the view is initialized will result in undefined.

• Use @ViewChildren to access an array of child components if you need to interact with multiple instances.

• Consider using template reference variables for simpler scenarios or when you don't need direct access to the component instance.

• Prioritize data binding over ViewChild whenever possible for better component-driven development and encapsulation.

By following these steps and understanding the key points, you can effectively use ViewChild to access and interact with child components from parent components in your Angular applications.