Angular is a powerful JavaScript framework for building web applications, but as your application grows, it can become slow and difficult to manage. Angular performance tuning is an important part of ensuring that your Angular app runs smoothly and efficiently.
In this article, we will explore some tips and tricks for optimising the performance of your Angular application, including techniques for improving the load time, reducing the size of your application, and reducing the number of unnecessary DOM updates. Whether you’re a seasoned Angular developer or just getting started, these tips and tricks will help you improve the performance of your application and ensure that it runs smoothly for your users.
So, let’s begin with the primary techniques for easy angular app performance tuning.
Tips for Angular Performance Tuning
There are various tips through which you can easily improve the performance of your angular app. However, we have picked six best angular app optimization tips for you. Here they are:
- Using AoT Compilation
- Using OnPush Change Detection Strategy
- Use pure pipes
- Using TrackBy on ngFor
- Code Splitting
- Improving page load
Let’s learn about each of them in detail.
Using AoT Compilation
One important tip for improving the performance of your Angular application is to use Ahead-of-Time (AoT) compilation. AoT is a technique that pre-compiles your Angular components and templates at build time, rather than compiling them at runtime. This can significantly improve the load time of your application, as the browser does not need to spend time compiling the templates and components when the application is first loaded.
AoT also helps to reduce the size of your application by inlining the templates and component factories in the JavaScript code. This reduces the number of network requests needed to load the application, and reduces the overall size of the application, which can help to improve the load time.
To enable AoT compilation in your Angular application, you need to use the Angular CLI to build your application with the “–aot” flag. This will enable AoT compilation for your application, and the resulting build will be optimised for performance. Additionally, you can use tools like the “ngc” compiler directly, which is the command line tool that Angular CLI uses for AoT compilation.
Use OnPush Change Detection Strategy
The OnPush change detection strategy is a way to improve the performance of an Angular application by only checking for changes in a component when an input property changes or an event is emitted. This is opposed to the default “OnPush” strategy, which checks for changes in a component and all of its child components every time there is a change detection cycle.
To use the OnPush strategy, you need to import the ChangeDetectorRef module and set the changeDetection property of your component’s @Component decorator to ChangeDetectionStrategy.OnPush.
OnPush is a powerful strategy that can improve the performance of your application, but it can also make it more complex. Be sure to test your application thoroughly after implementing this strategy to ensure that it is working as expected.
Use pure pipes
A pure pipe in Angular is a pipe that only runs when there is a change in the input value or the parameters passed to the pipe. This can improve the performance of an Angular application because it reduces the number of times a pipe is run.
To create a pure pipe in Angular, you need to add the pure: true property to the @Pipe decorator of your pipe.
It is important to note that when you create a pure pipe, Angular will only re-run the pipe when the input value or parameters passed to the pipe change. If the pipe relies on other data or state that is not passed as input, the pipe may not produce the correct output.
It’s also worth noting that, if you have a pure pipe inside a component which uses OnPush change detection strategy, it would only execute the pipe when an Input or an event emitted, which can further boost the performance of your application.
Keep in mind that, if you are using a pure pipe with a complex function, it could have a negative impact on the performance of your application because the pipe will not execute until the input value changes. In such cases, it’s better to use impure pipes.
Using TrackBy on ngFor
trackBy is a feature in Angular that allows you to specify a unique identifier for each item in an ngFor loop. This can improve the performance of an Angular application by reducing the number of DOM elements that need to be created and destroyed when the collection changes.
To use trackBy in an ngFor loop, you need to pass a function as the value of the trackBy attribute. The function should take in the index of the current item and the item itself, and return a unique identifier for that item.
<div *ngFor=”let item of items; trackBy: trackByFn”>{{ item.name }}</div>
trackByFn(index: number, item: any) {
return item.id;
}
In this example, the trackByFn function is returning the unique identifier of each item as its id property.
Code Splitting
Code splitting is a technique used to improve the performance of Angular applications by reducing the initial load time of the application. It involves breaking up the application’s code into smaller, more manageable chunks that can be loaded on demand as the user navigates through the application.
This allows the application to load only the code that is needed for the current page, rather than loading all of the code at once, which can significantly improve the initial load time of the application. This technique can be implemented using the Angular Router module and the loadChildren property.
Improving page load
There are several ways to improve the page load of an Angular application, some of which include:
- Code splitting: As mentioned before, code splitting is a technique that involves breaking up the application’s code into smaller chunks that can be loaded on demand. This can significantly improve the initial load time of the application.
- Lazy loading: Lazy loading is a technique that involves loading modules only when they are needed. This can also help improve the initial load time of the application by reducing the amount of code that needs to be loaded on the initial load.
- Optimising images: Optimising images by compressing them and using the appropriate image format can also help improve the page load by reducing the size of the images that need to be downloaded.
- Use of browser caching: Enabling browser caching can also help improve the page load by allowing the browser to store resources locally, so that they don’t have to be downloaded again.
Final Words
In conclusion, Angular is a powerful and versatile framework that can be used to build complex, high-performance web applications. However, as with any framework, there are certain best practices and techniques that can be used to optimise the performance of an Angular application. By utilising techniques such as code splitting, lazy loading, etc., developers can significantly improve the load time and overall performance of their Angular applications.
Smarsh Infotech, a popular IT services outsourcing company can be your future application development partner. If you are planning to develop your business on digital platforms, we can help you in any manner we can. Let’s connect and discuss your project ideas.
Also Read: The New Angular 14: Read all about it
