13 Mistakes Committed by Angular JS Developers
Have you made any of these mistakes? We take a look at thirteen mistakes made by Angular developers, why they're bad, and what you can do to avoid them.
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1. Keep a Track on the Count of Watchers
Angular creates a watcher for every binding. Evaluation and comparison for previous bindings are done at each digest phase. In the end, the number of watchers comes out to be huge. A few watchers are okay but these watchers start getting troublesome when there are hundreds and thousands of them in the code, eventually slowing down the performance of an application in the browser. The Angular community has a standard global maximum limit of 2,000 watchers, so it's better to keep track of the count of watchers from the very beginning of development. Some developers can write code which counts watchers and thus help in modifying and optimizing the code later.
2. Inability to Use the Available Tools
This is one of the most disappointing circumstances since it becomes necessary to utilize a tool sooner or later. For instance, Firefox and Chrome incorporate uncommon improvement strings that involve investigation, mistake yields, and profiling. With the help of these instruments, a developer can discover the errors quickly and save a lot of time.
3. Not Compartmentalizing Properly
Compartmentalizing your code is the core part of coding in Angular. When you work with MVC, the general concept is that you have a Controller for a View. The controller is your rationale layer, and it's imperative that inside this layer you make compact compartments for each area of your applications. A typical oversight is to put the excessive concept into one controller. On the off chance that you have to separate your layer for your application to make sense, don't take alternate routes. Rather, make smaller sorted out units for your logic layer.
Code organization is one of the most crucial parts of application building. It won't seem of much importance initially but when you have a team of developers working on the same project, it's easier to work on, find errors, and develop smaller parts individually. A well-organized code makes the application adaptable for development, which helps as the organization grows.
4. Falling Back Into jQuery
jQuery is a customary library for handling events and for making DOM manipulations easier. Angular, on the other hand, is a framework that is used for the creation of scalable applications, testing, and development of applications and hence it cannot be utilized in the amplification of HTML documents. Angular possess an ample amount of features and, so, a developer should know about all the available features before involving jQuery in the development. Even if you need DOM manipulations, it doesn't necessarily mean that you have to use jQuery.
5. Improper Use Of Event Handlers
Angular can be perfect specifically when it comes to appending functionality grounded on forecasted data, like boasting a button based on user input. However, this goes against one of the basic principles of the Angular, which is to keep all the logic and display sorted.
6. Don't Forget to Test!
Not testing an application before its release is a common mistake among developers because they don't understand the fact that different environments can introduce bugs.
You don't need to acquire an environment with every operating system, rather you should test your application using popular cross-browser testing tools.
7. Fail to Utilize Batarang
Batarang is an extraordinary Google Chrome extension which is employed for debugging and developing Angular applications. Batarang can be useful when operating on abstracting scopes where arguments are limited. Avoid the common mistake of not utilizing this tool to its full potential.
8. Fixed Scope Binding
Normally, Angular provides its very own scoping rules. The simple use of information sources limited to a model, for example, can prompt a breakdown in the binding system. However, the complexities come down to making sure that the names are fully upgraded. Non-primitives in Angular are passed by references whereas primitives are passed by the value. To bring this problem to an end, the developer needs to assemble their scope objects properly.
9. Forget to Unsubscribe
There are two scenarios where unsubscribing grows into a major risk. First, you ignite the lifecycle hook by yourself if it's a service that you have a subscription to, and second, you stimulate the OnDestroy lifecycle hook if it's in a constituent that you've subscribed to. Keep a check on these to avoid any complications later.
10. Declaring Everything With Anonymous Functions
Be sure to assign your functions and objects accounts for tidy and maintainable code. This kind of well-maintained and documented code is easy to work with and can easily be divided into files. Not just this, such pieces of code have an increased testability. This makes it easy for the developer to maintain the application code and gives more expressibility to the code.
11. Direct Manipulation of the DOM
This is the most common mistake that every new Angular developer commits. Whether it involves rendering SVG or refreshing a web page's heading on a context change, it can be tempting to take the easy way out and makes changes to the DOM directly. Angular developers should never be tempted to alter the DOM directly.
12. Not Using $applyAsync
Because there is a polling method,
$digest(), in Angular, it is just implemented because of the subsisting directives.
$applyAsync aids a lot in maintaining the expressiveness of code inthe next cycle of
$digest(). There is both an automated and manual way to use
13. Declaration of the Same Component in More Than One NgModule
Declaring a component in multiple NgModules is one of the most recurrent mistakes among Angular developers that end up throwing up error on your screen. This error occurs because one needs to mention each component in the scope of its own NgModule. Every component can belong to only one NgModule. In case you want to make use of any component, the current NgModule must know about it.
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