Angular – Lazy Loading & Dynamic Rendering with ViewContainerRef / ngComponentOutlet

Angular provides several ways to dynamically render components, and one popular method is using ViewContainerRef and ngComponentOutlet. This allows for lazy loading of components and dynamic rendering based on certain conditions.

Lazy Loading

Lazy loading is a technique used to defer the loading of certain components until they are actually needed. This can provide a performance boost by only loading what is necessary at the time. ViewContainerRef is a class provided by Angular that allows for dynamic rendering of components within a view. It acts as a container for the components and provides methods for adding, removing, and manipulating them.

Dynamic Rendering

With ViewContainerRef and ngComponentOutlet, you can dynamically render components based on conditions such as user actions, API responses, or other parts of the application state. This allows for a more flexible and dynamic user interface, as components can be added or removed based on the current context.

Using ViewContainerRef / ngComponentOutlet

To use ViewContainerRef and ngComponentOutlet, you would typically create a directive that contains the logic for dynamically rendering components. This directive would then be added to the HTML template where you want the dynamic rendering to occur.

“`html

“`

In the component class, you would use ViewChild to get a reference to the ng-container element and then use ViewContainerRef methods to add or remove components based on the application logic.

“`javascript
import { Component, ViewChild, ViewContainerRef } from ‘@angular/core’;

@Component({
selector: ‘app-dynamic-rendering’,
template: “
})
export class DynamicRenderingComponent {
@ViewChild(‘container’, { read: ViewContainerRef }) container: ViewContainerRef;

// Use container methods to add or remove components
}
“`

Conclusion

ViewContainerRef and ngComponentOutlet provide a powerful way to achieve lazy loading and dynamic rendering of components in Angular. By using these techniques, you can create a more flexible and responsive user interface that only loads what is necessary at the time. This can lead to better performance and a more seamless user experience.