What is AngularJS?
AngularJS is an open-source, client-side JavaScript MVC (Module-View-Controller) framework to develop a dynamic web application. AngularJS was originally started by Google as a project in 2010 to encounter challenges in developing single-page applications. But now, it is an open-source framework. AngularJS is entirely based on JavaScript and HTML and, so there is no need to learn another syntax or language for it.
Some of the Basic Features and Advantages of AngularJS:
- Supported by Google
- Open-source JavaScript MVC framework.
- No need to learn another scripting language. It’s just pure JavaScript and HTML.
- Built-in attributes (directives) make HTML dynamic.
- Supports separation of concerns by using MVC (Module-View-Controller) design pattern.
- Easy to extend and customize.
- Easy to Unit test.
- REST friendly.
- Supports Single Page Application.
- Uses Dependency Injection.
- Tips to Optimize AngularJS Performance
There are numerous built-in tools to optimize AngularJS, but the performance issue still shows some loopholes in the framework. When working with AngularJS, if you don’t have a huge infrastructure like Google and any other technology giant company, then you need to take some preventative measures or adopt the best practices to enhance AngularJS performance to amplify the application.
Before going further towards the tips to boost the performance of AngularJS, it is recommended to always keep some room to enhance the performance, despite being satisfied with the current position and not looking out of the box.
Here are the following tips to elevate the performance of AngularJS:
- Use of ‘scope.$evalAsync’ in AngularJS
While the digest cycle is already in operation and running, and you try to start it manually, then you are definitely going to get an error in it. Therefore, to avert yourself from this kind of situation, use “scope.$evalAsync” in the place of $apply, to initiate the digest cycle manually without an error.
The code queues up the operation to be performed at the end of the current cycle without blowing up the current or new one. It will restrain you from getting errors and increase the lag time of the digest cycle. - Limit your Watchers to enhance AngularJS
By implementing data-binding at any time you can generate more $$watchers and $scopes, which will enlarge the digest cycle. Too many $$watchers can widen the lag time, therefore they favor using it in a limited way and avoid using it as much as possible.
As we understand in the above-given point, the small digest cycle will result in an enhanced AngularJS performance. Accordingly, make sure to limit your watchers and prevent long digest cycles. - Limited DOM Access
The access to DOM is quite costly, so always try to keep the DOM tree as small as possible. If it is attainable, then don’t try to alter the DOM and don’t set an inline style to avoid the reflow of JavaScript.
Limited use of DOM can boost the performance of AngularJS and minimize the expenses too. - Careful Observation of Digest Cycle to improve AngularJS
The digest cycle is considered the best indicator of AngularJS application performance. The cycle helps to check and monitor the changes in the variable while working on a loop. Therefore, try to maintain the digest cycle shorter to make your application run fast and smoothly.
It will boost the performance of the application and deliver good results from the customers. A fair-performing application will automatically attract more users and give a boost to the market. - Use the Chrome DevTools Profiler and Timeline
Chrome’s both the DevTools Profiler and Timeline can help in finding the blockage situations and perform as a guide to improve the efforts. Both the tools work productively to optimize AngularJS web and application performance.
Chrome Developer Tools and Chrome DevTools are web authoring and debugging built into the browser. They provide access to applications and web browsers and help programmers for deeper access. These tools allow programmers to perform diverse tasks stretch from testing the viewport on the mobile device to the editing of the website or even measure the performance of the whole website or an individual asset also. - Avoid ‘ng-repeat’ to enhance AngularJS Development
Too much use of the ‘ng-repeat’ directive can extremely affect the overall performance of the web application. Yet, to reduce its effect, there are other alternatives present. For instance, in the place of using ‘ng-repeat’ to render the global navigation, developers can create their own by using the ‘$interpolate’. It is a provider to furnish the template against an object before converting it into a DOM node. - Use Lodash to boost AngularJS
The Lodash tool in AngularJS helps developers to write the application’s logic quickly and improve the built-in AngularJS methods and optimize the application’s performance. However, suppose the Lodash is not used in the already existing web application to boost its performance. In that case, the developers can rewrite the process with the help of native JavaScript.
This tool empowers developers to enhance the performance of AngularJS web applications, apart from that they can write the process on their own. It is one of the effective tools for AngularJS development. - Use ‘ng-switch’ or ‘ng-if’ rather than ‘ng-show’
The directive ‘ng-show’ simply toggles the CSS display on or off for a certain element.
To remove an element from the DOM, the developers must use ‘ng-switch or ‘ng-if’. It is another superb tip to optimize AngularJS web applications.
- Use $filter to enhance AngularJS
AngularJS development in a web application runs the DOM (Document Object Model) filter twice during each digest cycle. During the first DOM filter run, it detects changes, while in the second run, it updates the values that have changed. However, to make this whole cycle process a time saver, the $filter provider permits pre-process data before it is sent to the View and, after that, bounces the DOM parsing process completely.
It is an amazing tool to optimize the speed of the web application and the AngularJS development process to save time and improve the application’s overall effectiveness and efficiency. - Disable Comment Directives and CSS Class
While building a directive, the developers can assign it to be used as an attribute, comments, element, or CSS class. However, if you don’t need comment directives and CSS classes, it can disable them to optimize the AngularJS application’s performance. - Employ ‘$cacheFactory’ to Optimize AngularJS
If the developer needs to store the data that may possibly be required and calculated after a period of time, then prefer to use the ‘$cacheFactory’ directive. - Disable Data Debugging
The Protractor and Batarang tools rely on data binding and scopes with which AngularJS attaches to DOM elements. Therefore, after completing debugging, aim to disable the extra data so that it doesn’t lower the application performance.
Disabling the data debugging boosts the performance of AngularJS and increases the performance of the web application also. - Use ‘console.time’
While facing and struggling with an issue in debugging, ‘console.time’ tool in Chrome DevTools is a magnificent option and tool for calculating the execution time and accumulating other performance benchmarks.
It is a superb and very helpful tool in managing issues while debugging and calculating different performance benchmarks to optimize AngularJS development. - Use ‘ng-model’
Debouncing inputs by using directive ‘ng-model’ can play a crucial role in controlling the digest cycle.
For Example, implementing ng-model-options=”{debounce:200}” can guarantee that the digest cycle doesn’t run more than once in every 20ms. It is a noteworthy tool to limit the digest cycle and ultimately optimize the performance of the AngularJS development. - Use ‘$watchCollection’
While using $watchCollection, a maximum of up to two parameters is a great choice, but three or more than three parameters are like a crowd and create disorder. The addition of a third parameter drives AngularJS to go through intense checking and ends up in the requirement of a lot of resources in use.
The developers can do excellent work with having around the ‘$watchCollection’. It works as a third parameter for $watch. In spite of that, it checks the first layer of each object’s properties so that it won’t slow down the overall speed and efficiency of the AngularJS web applications. - Use Pure Pipes to Optimize AngularJS
AngularJS uses pipes to show model values on the UI (User Interface) in a slightly different format. For Example, ‘date | shortdate’. Here, the short date filter will convert date objects in a small format like ‘DD/MM/YYYY’. Pipes are used for slicing and dicing the data for display purposes. The Pipes are classified into two sections, i.e., “Pure Pipe” and “Impure Pipe”.
The difference between Pure pipe and Impure Pipe is that Impure Pipe can deliver multiple-output for a similar input over time. However, the Pure Pipes perform a function that can produce similar output for the same input data.
AngularJS has some in-built pipes, and all of them are pure in nature. Therefore, when it is preferred to binding evaluation, each time Angular evaluates an expression and then applies the pipe over it (if it exists). - Infinite Pagination or Scrolling
It is a very effective and brilliant enhancing strategy as if everything stops performing or fails, then it will work. You can reduce the number of looped elements by implementing the Infinite Pagination or Scrolling technique. To serve this motive, AngularJS has a directive called ‘ngInfiniteScroll’. - Inelastic Scoping
In this tip, JavaScript garbage collectors will free up the memory that is getting absorbed uselessly and periodically to fasten the process. It will help provide the required resources for the upcoming functions and speed up the application’s work. It is a widespread and easy way to boost AngularJS performance.