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Learn how to seamlessly connect child components to parent functions in Angular 11 using services and observables. Perfect for managing nested components!
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How to Call Parent Function from Child Component in Angular 11

In Angular development, communication between parent and child components is crucial to creating dynamic and interactive applications. However, challenges arise when dealing with more complex component hierarchies, especially when using intermediary components like tabs. In this guide, we will explore a common problem where a child component needs to call a function in a parent component, particularly in an Angular 11 application. We’ll provide a step-by-step solution using a shared service.

The Problem

You may find yourself in a situation where you have the following structure in your Angular application:

A parent component (e.g., home.component)

A child component (e.g., tasks.component)

An intermediate tabs component that loads the child component in a tab

In this scenario, if the child component (in a tab) wants to communicate with its parent component, the conventional @ Output methods might not work as expected, particularly because the @ Output needs to be directed back to the direct parent component, not through an intermediary.

Example Structure

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In this HTML structure, the onId method in the home.component.ts is meant to get triggered by an event emitted from the child component. However, when you try to call a function in tasks.component, things get complicated.

The Solution: Using a Shared Service

Step 1: Create a Notification Service

To facilitate communication between components, especially when they are nested, we can create a shared service using Angular’s dependency injection. This pattern will help transmit events or values across components seamlessly.

Create notification.service.ts

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Step 2: Register the Service in Module Providers

Make sure to provide this service in your Angular module so it can be injected throughout your application.

Step 3: Modify the Child Component

Now let’s update the tasks.component to utilize the newly created service. The child component will call the taskPlayed method when an action occurs (e.g., when a button is clicked).

Update tasks.component.ts

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Step 4: Handle the Event in the Parent Component

In the parent component, you will need to subscribe to the taskPlayed$ observable to listen for events emitted by the child component.

Update home.component.ts

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Conclusion

By implementing a shared service, you can create a robust communication pathway between child and parent components, even through intermediate components like tab navigators. This approach is both flexible and scalable, allowing you to pass various types of data, such as numbers, objects, or even arrays.

With this solution, you’ll find that your Angular applications become much more interactive and maintainable. Feel free to adapt the service to fit your specific data needs as your application grows!

Now, you can communicate effortlessly between components by using observables, making your application more dynamic and responsive to user actions!