Angular 16 is the biggest release since the initial rollout of Angular, and it changes everything: Bye bye zones, change-detection, life-cycle, children-selectors, Rx and what not.
Recorded webinar based on these slides given by Yaron Biton, Misterbit Coding-Academy’s CTO, can be found at: https://www.youtube.com/watch?v=92K1fgPbku8
Coding-Academy offers advanced web-techs training and software development services: Top-rated Full-stack courses for Angular, React, Vue, Node, Modern architectures, etc. | Available top-notch on-demand-coders trough Misterbit technological solutions | Coding-Academy Bootcamp: Hundreds of employed full-stack developers every year | Anything web, end to end projects | Tech companies and startups | Consulting to management and dev teams | Workshops for managers and leaders.
Http Service will help us fetch external data, post to it, etc. We need to import the http module to make use of the http service. Let us consider an example to understand how to make use of the http service.
In this comprehensive guide, Angular is described as a one-stop solution for front-end development. Learn everything there is to know about Angular, including how it works, why, and the benefits.
Presentation about new Angular 9.
It gives introduction about angular framework.
Provides information about why we use angular,
additional features and fixes from old versions. It will clearly explain how to create a new angular project and how to use angular commands and their usages.
It will also explain about the key components like angular architecture, routing, dependency injection etc.,
Http Service will help us fetch external data, post to it, etc. We need to import the http module to make use of the http service. Let us consider an example to understand how to make use of the http service.
In this comprehensive guide, Angular is described as a one-stop solution for front-end development. Learn everything there is to know about Angular, including how it works, why, and the benefits.
Presentation about new Angular 9.
It gives introduction about angular framework.
Provides information about why we use angular,
additional features and fixes from old versions. It will clearly explain how to create a new angular project and how to use angular commands and their usages.
It will also explain about the key components like angular architecture, routing, dependency injection etc.,
As presented at DevDuck #6 - JavaScript meetup for developers (www.devduck.pl)
----
Looking for a company to build your app? - Check us out at www.brainhub.eu
Introduction to angular with a simple but complete projectJadson Santos
A simple front end project with angular. Its show how to create your first components, include bootstrap templates, create routes and build the project to production.
Angular 14: What's new! explore in-depth the features of Angular 14 and learn how to get started with it. Angular 14 has been released with several significant features.
The Lifecycle Hooks makes every complex state management easier and simpler, so let's explore the Lifecycle Hooks of Angular to fine-tune the behavior of our components.
AngularJS is a structural framework for dynamic web apps. It lets you use HTML as your template language and lets you extend HTML's syntax to express your application's components clearly and succinctly. AngularJS's data binding and dependency injection eliminate much of the code you would otherwise have to write. And it all happens within the browser, making it an ideal partner with any server technology.
NgRx is a framework for building reactive applications in Angular with the Management of States. NgRx is inspired by the Redux pattern - unifying the events in your application and deriving state using RxJS.
At a high level, NgRx stores a single state and uses actions to express state changes. It makes Angular development easier by simplifying the application’s state in objects and enforcing unidirectional data flow.
It is established with 5 main components - Store, Actions, Reducers, Selectors, and Effects.
Components are the most basic UI building block of an Angular app. An Angular app contains a tree of Angular components.
Angular components are a subset of directives, always associated with a template. Unlike other directives, only one component can be instantiated per an element in a template.
A component must belong to an NgModule in order for it to be available to another component or application. To make it a member of an NgModule, list it in the declarations field of the NgModule metadata.
A directive is a custom HTML element that is used to extend the power of HTML. Angular 2 has the following directives that get called as part of the BrowserModule module.
ngif
ngFor
If you view the app.module.ts file, you will see the following code and the BrowserModule module defined. By defining this module, you will have access to the 2 directives.
This Edureka "Angular Directives" tutorial will help you to learn about different directives in Angular 2. Below are the topics covered in this tutorial:
1) Why we need Angular Directive?
2) What is Angular Directive?
3) Types of Angular Directive
4) Built-in Angular Directives
5) Working with Custom Angular Directives
Subscribe to our channel to get updates. Check our complete Angular playlist here: https://goo.gl/09KsDC
Probabilmente il framework javascript più atteso di sempre, evoluzione di uno dei framework più longevi ed usati nello sviluppo front end. Si vedranno alcune delle novità introdotte e delle scelte radicali fatte da Google per la nuova versione di Angular
As presented at DevDuck #6 - JavaScript meetup for developers (www.devduck.pl)
----
Looking for a company to build your app? - Check us out at www.brainhub.eu
Introduction to angular with a simple but complete projectJadson Santos
A simple front end project with angular. Its show how to create your first components, include bootstrap templates, create routes and build the project to production.
Angular 14: What's new! explore in-depth the features of Angular 14 and learn how to get started with it. Angular 14 has been released with several significant features.
The Lifecycle Hooks makes every complex state management easier and simpler, so let's explore the Lifecycle Hooks of Angular to fine-tune the behavior of our components.
AngularJS is a structural framework for dynamic web apps. It lets you use HTML as your template language and lets you extend HTML's syntax to express your application's components clearly and succinctly. AngularJS's data binding and dependency injection eliminate much of the code you would otherwise have to write. And it all happens within the browser, making it an ideal partner with any server technology.
NgRx is a framework for building reactive applications in Angular with the Management of States. NgRx is inspired by the Redux pattern - unifying the events in your application and deriving state using RxJS.
At a high level, NgRx stores a single state and uses actions to express state changes. It makes Angular development easier by simplifying the application’s state in objects and enforcing unidirectional data flow.
It is established with 5 main components - Store, Actions, Reducers, Selectors, and Effects.
Components are the most basic UI building block of an Angular app. An Angular app contains a tree of Angular components.
Angular components are a subset of directives, always associated with a template. Unlike other directives, only one component can be instantiated per an element in a template.
A component must belong to an NgModule in order for it to be available to another component or application. To make it a member of an NgModule, list it in the declarations field of the NgModule metadata.
A directive is a custom HTML element that is used to extend the power of HTML. Angular 2 has the following directives that get called as part of the BrowserModule module.
ngif
ngFor
If you view the app.module.ts file, you will see the following code and the BrowserModule module defined. By defining this module, you will have access to the 2 directives.
This Edureka "Angular Directives" tutorial will help you to learn about different directives in Angular 2. Below are the topics covered in this tutorial:
1) Why we need Angular Directive?
2) What is Angular Directive?
3) Types of Angular Directive
4) Built-in Angular Directives
5) Working with Custom Angular Directives
Subscribe to our channel to get updates. Check our complete Angular playlist here: https://goo.gl/09KsDC
Probabilmente il framework javascript più atteso di sempre, evoluzione di uno dei framework più longevi ed usati nello sviluppo front end. Si vedranno alcune delle novità introdotte e delle scelte radicali fatte da Google per la nuova versione di Angular
Slides of a talk of a seminars series I gave at WebRatio in January 2014.
I implemented many best practices and advices in this presentation in a generic app template available here: https://github.com/iivanoo/cordovaboilerplate
In this talk, I'm presenting an alternative approach to thinking about UI and navigation on iOS - one that is declarative and that I find easy to reason about in a big application. I did live coding and the link is on the last slide. Enjoy!
Taming event-driven software via formal verificationAdaCore
Event-driven software can be found everywhere, from low-level drivers, to software that controls and coordinates complex subcomponents, and even in GUIs. Typically, event-driven software is characterised as consisting of a number of stateful components that communicate by sending messages to each other. Event-driven software is notoriously difficult to test. There are often many different sequences of events, and because the exact order of the events will affect the state of the system, it can be easy for bugs to lurk in obscure un-tested sequences of events. Even worse, reproducing these bugs can be difficult due to the need to reproduce the exact sequence of events that led to the issue.
Formal verification is one method of solving this: rather than writing tests to check each of the different possible sequences of events, automated formal verification could be used to verify that the software is correct no matter what sequence of events is observed. In this talk, we will look at what capabilities are required to ensure that this will be successful, including what it means for event-driven software to be correct, and how to ensure that the verification can scale to industrial-sized software projects.
An introduction to the complex single page web application framework known as AngularJs. An attempt to overview the high-level aspects of the framework, and to supply references for further exploration.
Top 7 Angular Best Practices to Organize Your Angular AppKaty Slemon
Learn about Angular best practices to improve the performance of your existing Angular application. Tried and tested clean code checklist for your Angular app.
Modern design is crucial in today's digital environment, and this is especially true for SharePoint intranets. The design of these digital hubs is critical to user engagement and productivity enhancement. They are the cornerstone of internal collaboration and interaction within enterprises.
Climate Science Flows: Enabling Petabyte-Scale Climate Analysis with the Eart...Globus
The Earth System Grid Federation (ESGF) is a global network of data servers that archives and distributes the planet’s largest collection of Earth system model output for thousands of climate and environmental scientists worldwide. Many of these petabyte-scale data archives are located in proximity to large high-performance computing (HPC) or cloud computing resources, but the primary workflow for data users consists of transferring data, and applying computations on a different system. As a part of the ESGF 2.0 US project (funded by the United States Department of Energy Office of Science), we developed pre-defined data workflows, which can be run on-demand, capable of applying many data reduction and data analysis to the large ESGF data archives, transferring only the resultant analysis (ex. visualizations, smaller data files). In this talk, we will showcase a few of these workflows, highlighting how Globus Flows can be used for petabyte-scale climate analysis.
Prosigns: Transforming Business with Tailored Technology SolutionsProsigns
Unlocking Business Potential: Tailored Technology Solutions by Prosigns
Discover how Prosigns, a leading technology solutions provider, partners with businesses to drive innovation and success. Our presentation showcases our comprehensive range of services, including custom software development, web and mobile app development, AI & ML solutions, blockchain integration, DevOps services, and Microsoft Dynamics 365 support.
Custom Software Development: Prosigns specializes in creating bespoke software solutions that cater to your unique business needs. Our team of experts works closely with you to understand your requirements and deliver tailor-made software that enhances efficiency and drives growth.
Web and Mobile App Development: From responsive websites to intuitive mobile applications, Prosigns develops cutting-edge solutions that engage users and deliver seamless experiences across devices.
AI & ML Solutions: Harnessing the power of Artificial Intelligence and Machine Learning, Prosigns provides smart solutions that automate processes, provide valuable insights, and drive informed decision-making.
Blockchain Integration: Prosigns offers comprehensive blockchain solutions, including development, integration, and consulting services, enabling businesses to leverage blockchain technology for enhanced security, transparency, and efficiency.
DevOps Services: Prosigns' DevOps services streamline development and operations processes, ensuring faster and more reliable software delivery through automation and continuous integration.
Microsoft Dynamics 365 Support: Prosigns provides comprehensive support and maintenance services for Microsoft Dynamics 365, ensuring your system is always up-to-date, secure, and running smoothly.
Learn how our collaborative approach and dedication to excellence help businesses achieve their goals and stay ahead in today's digital landscape. From concept to deployment, Prosigns is your trusted partner for transforming ideas into reality and unlocking the full potential of your business.
Join us on a journey of innovation and growth. Let's partner for success with Prosigns.
How Recreation Management Software Can Streamline Your Operations.pptxwottaspaceseo
Recreation management software streamlines operations by automating key tasks such as scheduling, registration, and payment processing, reducing manual workload and errors. It provides centralized management of facilities, classes, and events, ensuring efficient resource allocation and facility usage. The software offers user-friendly online portals for easy access to bookings and program information, enhancing customer experience. Real-time reporting and data analytics deliver insights into attendance and preferences, aiding in strategic decision-making. Additionally, effective communication tools keep participants and staff informed with timely updates. Overall, recreation management software enhances efficiency, improves service delivery, and boosts customer satisfaction.
Multiple Your Crypto Portfolio with the Innovative Features of Advanced Crypt...Hivelance Technology
Cryptocurrency trading bots are computer programs designed to automate buying, selling, and managing cryptocurrency transactions. These bots utilize advanced algorithms and machine learning techniques to analyze market data, identify trading opportunities, and execute trades on behalf of their users. By automating the decision-making process, crypto trading bots can react to market changes faster than human traders
Hivelance, a leading provider of cryptocurrency trading bot development services, stands out as the premier choice for crypto traders and developers. Hivelance boasts a team of seasoned cryptocurrency experts and software engineers who deeply understand the crypto market and the latest trends in automated trading, Hivelance leverages the latest technologies and tools in the industry, including advanced AI and machine learning algorithms, to create highly efficient and adaptable crypto trading bots
Why React Native as a Strategic Advantage for Startup Innovation.pdfayushiqss
Do you know that React Native is being increasingly adopted by startups as well as big companies in the mobile app development industry? Big names like Facebook, Instagram, and Pinterest have already integrated this robust open-source framework.
In fact, according to a report by Statista, the number of React Native developers has been steadily increasing over the years, reaching an estimated 1.9 million by the end of 2024. This means that the demand for this framework in the job market has been growing making it a valuable skill.
But what makes React Native so popular for mobile application development? It offers excellent cross-platform capabilities among other benefits. This way, with React Native, developers can write code once and run it on both iOS and Android devices thus saving time and resources leading to shorter development cycles hence faster time-to-market for your app.
Let’s take the example of a startup, which wanted to release their app on both iOS and Android at once. Through the use of React Native they managed to create an app and bring it into the market within a very short period. This helped them gain an advantage over their competitors because they had access to a large user base who were able to generate revenue quickly for them.
Field Employee Tracking System| MiTrack App| Best Employee Tracking Solution|...informapgpstrackings
Keep tabs on your field staff effortlessly with Informap Technology Centre LLC. Real-time tracking, task assignment, and smart features for efficient management. Request a live demo today!
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SOCRadar Research Team: Latest Activities of IntelBrokerSOCRadar
The European Union Agency for Law Enforcement Cooperation (Europol) has suffered an alleged data breach after a notorious threat actor claimed to have exfiltrated data from its systems. Infamous data leaker IntelBroker posted on the even more infamous BreachForums hacking forum, saying that Europol suffered a data breach this month.
The alleged breach affected Europol agencies CCSE, EC3, Europol Platform for Experts, Law Enforcement Forum, and SIRIUS. Infiltration of these entities can disrupt ongoing investigations and compromise sensitive intelligence shared among international law enforcement agencies.
However, this is neither the first nor the last activity of IntekBroker. We have compiled for you what happened in the last few days. To track such hacker activities on dark web sources like hacker forums, private Telegram channels, and other hidden platforms where cyber threats often originate, you can check SOCRadar’s Dark Web News.
Stay Informed on Threat Actors’ Activity on the Dark Web with SOCRadar!
Your Digital Assistant.
Making complex approach simple. Straightforward process saves time. No more waiting to connect with people that matter to you. Safety first is not a cliché - Securely protect information in cloud storage to prevent any third party from accessing data.
Would you rather make your visitors feel burdened by making them wait? Or choose VizMan for a stress-free experience? VizMan is an automated visitor management system that works for any industries not limited to factories, societies, government institutes, and warehouses. A new age contactless way of logging information of visitors, employees, packages, and vehicles. VizMan is a digital logbook so it deters unnecessary use of paper or space since there is no requirement of bundles of registers that is left to collect dust in a corner of a room. Visitor’s essential details, helps in scheduling meetings for visitors and employees, and assists in supervising the attendance of the employees. With VizMan, visitors don’t need to wait for hours in long queues. VizMan handles visitors with the value they deserve because we know time is important to you.
Feasible Features
One Subscription, Four Modules – Admin, Employee, Receptionist, and Gatekeeper ensures confidentiality and prevents data from being manipulated
User Friendly – can be easily used on Android, iOS, and Web Interface
Multiple Accessibility – Log in through any device from any place at any time
One app for all industries – a Visitor Management System that works for any organisation.
Stress-free Sign-up
Visitor is registered and checked-in by the Receptionist
Host gets a notification, where they opt to Approve the meeting
Host notifies the Receptionist of the end of the meeting
Visitor is checked-out by the Receptionist
Host enters notes and remarks of the meeting
Customizable Components
Scheduling Meetings – Host can invite visitors for meetings and also approve, reject and reschedule meetings
Single/Bulk invites – Invitations can be sent individually to a visitor or collectively to many visitors
VIP Visitors – Additional security of data for VIP visitors to avoid misuse of information
Courier Management – Keeps a check on deliveries like commodities being delivered in and out of establishments
Alerts & Notifications – Get notified on SMS, email, and application
Parking Management – Manage availability of parking space
Individual log-in – Every user has their own log-in id
Visitor/Meeting Analytics – Evaluate notes and remarks of the meeting stored in the system
Visitor Management System is a secure and user friendly database manager that records, filters, tracks the visitors to your organization.
"Secure Your Premises with VizMan (VMS) – Get It Now"
Experience our free, in-depth three-part Tendenci Platform Corporate Membership Management workshop series! In Session 1 on May 14th, 2024, we began with an Introduction and Setup, mastering the configuration of your Corporate Membership Module settings to establish membership types, applications, and more. Then, on May 16th, 2024, in Session 2, we focused on binding individual members to a Corporate Membership and Corporate Reps, teaching you how to add individual members and assign Corporate Representatives to manage dues, renewals, and associated members. Finally, on May 28th, 2024, in Session 3, we covered questions and concerns, addressing any queries or issues you may have.
For more Tendenci AMS events, check out www.tendenci.com/events
Designing for Privacy in Amazon Web ServicesKrzysztofKkol1
Data privacy is one of the most critical issues that businesses face. This presentation shares insights on the principles and best practices for ensuring the resilience and security of your workload.
Drawing on a real-life project from the HR industry, the various challenges will be demonstrated: data protection, self-healing, business continuity, security, and transparency of data processing. This systematized approach allowed to create a secure AWS cloud infrastructure that not only met strict compliance rules but also exceeded the client's expectations.
We describe the deployment and use of Globus Compute for remote computation. This content is aimed at researchers who wish to compute on remote resources using a unified programming interface, as well as system administrators who will deploy and operate Globus Compute services on their research computing infrastructure.
How to Position Your Globus Data Portal for Success Ten Good PracticesGlobus
Science gateways allow science and engineering communities to access shared data, software, computing services, and instruments. Science gateways have gained a lot of traction in the last twenty years, as evidenced by projects such as the Science Gateways Community Institute (SGCI) and the Center of Excellence on Science Gateways (SGX3) in the US, The Australian Research Data Commons (ARDC) and its platforms in Australia, and the projects around Virtual Research Environments in Europe. A few mature frameworks have evolved with their different strengths and foci and have been taken up by a larger community such as the Globus Data Portal, Hubzero, Tapis, and Galaxy. However, even when gateways are built on successful frameworks, they continue to face the challenges of ongoing maintenance costs and how to meet the ever-expanding needs of the community they serve with enhanced features. It is not uncommon that gateways with compelling use cases are nonetheless unable to get past the prototype phase and become a full production service, or if they do, they don't survive more than a couple of years. While there is no guaranteed pathway to success, it seems likely that for any gateway there is a need for a strong community and/or solid funding streams to create and sustain its success. With over twenty years of examples to draw from, this presentation goes into detail for ten factors common to successful and enduring gateways that effectively serve as best practices for any new or developing gateway.
TROUBLESHOOTING 9 TYPES OF OUTOFMEMORYERRORTier1 app
Even though at surface level ‘java.lang.OutOfMemoryError’ appears as one single error; underlyingly there are 9 types of OutOfMemoryError. Each type of OutOfMemoryError has different causes, diagnosis approaches and solutions. This session equips you with the knowledge, tools, and techniques needed to troubleshoot and conquer OutOfMemoryError in all its forms, ensuring smoother, more efficient Java applications.
top nidhi software solution freedownloadvrstrong314
This presentation emphasizes the importance of data security and legal compliance for Nidhi companies in India. It highlights how online Nidhi software solutions, like Vector Nidhi Software, offer advanced features tailored to these needs. Key aspects include encryption, access controls, and audit trails to ensure data security. The software complies with regulatory guidelines from the MCA and RBI and adheres to Nidhi Rules, 2014. With customizable, user-friendly interfaces and real-time features, these Nidhi software solutions enhance efficiency, support growth, and provide exceptional member services. The presentation concludes with contact information for further inquiries.
4. Angular 16
This release has a significant impact
on any Angular team
Let's deep dive into
how to code modern Angular apps
5. • Anything web, end to end projects
• Tech companies and startups
• Consulting to management and dev teams
• Available on demand coders
https://www.misterbit.co.il
6. • Advanced web-techs training: Angular, React,
Vue, Node, Modern architectures, etc.
• Catchup workshops for managers and leaders
• Coding Academy bootcamp
• Advanced selective training - best practices
• Hundreds of employed full-stack developers
every year
https://www.coding-academy.org
7. Angular 16 features
We can (finally) use self-enclosing-tags!
Becomes:
<super-duper-long-component-name [prop]="someVar">
</super-duper-long-component-name>
<super-duper-long-component-name [prop]="someVar"/>
9. Angular 16 features –
Rethinking NgModules
Tooling for standalone components, directives
and pipes
// The schematics convert an existing project
// remove unnecessary NgModules classes,
// and change the bootstrap of the project to use standalone APIs:
ng generate @angular/core:standalone
// new projects as standalone from the start:
ng new --standalone
// Creates a simpler project without any NgModules and with
// generators that produce standalone directives, components, and pipes
// Generate a standalone component
ng generate componenet --standalone cmpName
10. Rethinking the CLI –
(As most modern CLIs )
> ng serve
// Vite development server!
Angular CLI is now Vite!
13. Preface
• On February 2023, Angular's team introduced
Signals to the framework with a simple pull
request.
• Since then, there have been a storm in the Angular
community about its use and benefits
• …and if it’s another rewrite of the framework
14. • In a model-driven web application, one of the main jobs
of the framework is synchronizing changes to the
application's data model and the UI.
• We refer to this mechanism as reactivity, and every
modern web framework has its own reactivity system.
Reactivity with Signals
15. Welcome Signals
• In modern Angular every piece of important data is
wrapped and used as signals
• So, signals become immediately the most basic and
important feature in Angular
16. Signals
• Angular Signals have an initial
value
• When executed, they return the
current value of the signal
quantity_ = signal<number>(1)
selectedCar_ = signal<Car>(null)
userMsg_ = signal({ txt: '', type: '' })
cars_ = signal<Car[]>([])
<h5> Quantity: {{ quantity_() }} </h5>
<user-msg [msg]="userMsg_()"></user-msg>
17. Setting Signal value
The signal function returns a WritableSignal<T>
which allow modifying the value:
// Replace the signal value
const movies_ = signal<Movie[]>([])
movies_.set([{ name: 'Fight club' }])
// Derive a new value
const someCount_ = signal<Number>(0)
someCount_.update(n => n + 1)
// Perform internal mutation of arrays and other objects
movies_.mutate(list => {
list.push({name: 'Aba Ganuv'})
})
18. computed values
computed() creates a memoizing signal, which
calculates its value from some other signals
const counter_ = signal(0)
// Automatically updates when `counter` changes:
const isEven_ = computed(() => counter_() % 2 === 0)
The value of the computed signal is being
recalculated whenever any of it's dependencies
changes.
19. computed() Signal
• The computed() function returns a Signal and not a
WritableSignal, which means it cannot be manually
modified (with set, update, or mutate)
• Instead, it is updated automatically whenever one
of its dependent signals change.
export function computed<T>(
computation: () => T, equal: ValueEqualityFn<T> = defaultEquals): Signal<T>
const moviesCount_ = computed(() => movies_().length)
20. side effect()
effect() schedules and runs a side-effectful function
Signal dependencies of this function are captured,
and the side effect is re-executed whenever any of
its dependencies produces a new value.
const counter_ = signal(0)
effect(() => console.log('The counter is:', counter_()))
// The counter is: 0
counter_.set(1)
// The counter is: 1
Effects do not execute synchronously with the set but are scheduled and resolved by
the framework. The exact timing of effects is unspecified.
21. effect() use cases
Effects are useful in specific situations.
Here are some examples:
• Performing custom rendering to a <canvas>
• Charting library, or other third party UI
library
• Keeping data in sync with window.localStorage
23. effect() registration
• Registering a new effect with the effect() function
requires an "injection context" (access to the
inject function).
• So we call either:
• Create the effect within a constructor
• Assign the effect to a field
• Pass an Injector to effect via its options:
@Component({...})
export class EffectiveCounterCmp {
readonly count_ = signal(0)
constructor(private injector: Injector) {}
initializeLogging(): void {
effect(() => {
console.log(`The count is: ${this.count_()})`)
}, {injector: this.injector})
}
}
24. effect() registration caveat
Registering an effect in the wrong place, produces a
weird message:
ngOnInit() {
effect(() => console.log(JSON.stringify(this.cars_())))
}
25. Into Signals
• Signal is a reactive value and is a producer that
notify consumers(dependents) when it changes.
• Any code that has registered an interest in the
Signal’s value is tracked as dependent.
• When the Signal’s value is modified, the Signal
will notify all of its dependents, allowing them to
react to the change in the Signal’s value.
26. Adding dependents (consumer) to a Signal
• When we use a signal in our template, this
dependency is being added to that signal
• We can add consumers by using effect and computed
functions.
27. Signal effect destroy
• effects are automatically destroyed when their
enclosing context is destroyed
• The effect() function gets an onCleanup function and
returns an EffectRef, that can be used for manually
destroy
• destroy(): 🧹 Shut down the effect, removing it
from any upcoming scheduled executions.
• The signature of the effect function:
export function effect(
effectFn: () => EffectCleanupFn | void, options?: CreateEffectOptions): EffectRef
28. Signal equality functions
• When creating a signal, we can optionally provide
an equality function
• It will be used to check whether the new value is
actually different than the previous one
import _ from 'lodash'
const data_ = signal(['test'], {equal: _.isEqual})
// Using deep equality - signal won't trigger any updates
data_.set(['test'])
29. untracking
reading without tracking dependencies
// You can prevent a signal read from being tracked by calling its getter with untracked:
effect(() => {
console.log(`User set to `${ currentUser_() }` and the counter is ${untracked(counter_)}`)
})
// Another example - invoke some external code which shouldn't be treated as a dependency:
effect(() => {
const user = currentUser_()
untracked(() => {
// If the `loggingService` reads signals, they won't be counted as
// dependencies of this effect.
this.loggingService.log(`User set to ${user}`)
})
})
31. The downfall of Global,
top-down change detection
"Angular's default strategy is to run change detection
over the entire component tree to make sure that the
DOM reflects the most up-to-date model.
Because Angular has no information about which
parts of the application state have actually changed,
it must check everything.
In practice, however, only a fraction of the entire
application state changes and only a handful of
components need to be re-rendered."
32. The downfall of onPush
"While the OnPush strategy can reduce
some of the performance cost, this
strategy is (very) limited:
change detection always starts from the root component
Additionally - OnPush components prevent their
descendants from being checked, descendent components
that depend on global state are not updated."
33. The downfall of the single traversal
"Angular's change detection was designed to refresh
application state once. The change detection process starts
from the root of the component tree and walks all components
down to the leaf nodes.
However, many common web interaction patterns roll up
descendant node states into ancestor nodes (e.g. form validity
is computed as a function of descendant control states).
This leads to the most "popular" error in Angular -
ExpressionChangedAfterItHasBeenCheckedError."
34. The downfall of Zone.js
"Crucially, zone.js does not provide "fine-grained"
information about changes in the model.
Zone.js is only capable of notifying us when
something might have happened in the application,
and can give no information about what happened or
what has changed."
35. The downfall of Zone.js
• "Large applications often grow to see
zone.js become a source of performance
issues and developer-facing complexity.
• As the web platform continues to evolve, it
also represents a rising maintenance cost
for the Angular team."
36. The downfall of Zone.js
Zone Pollution
https://angular.io/guide/change-detection-zone-pollution
@Component(...)
class AppComponent {
constructor(private ngZone: NgZone) { }
ngOnInit() {
this.ngZone.runOutsideAngular(() => {
// Sometimes we need to skip running change detection:
Plotly.newPlot('chart', data)
})
}
}
37. The downfall of Zone.js
async – await?...
WARNING: Zone.js does not support native async/await.
These blocks are not intercepted by zone.js and
will not trigger change detection.
See: https://github.com/angular/zone.js/pull/1140 for more information.
39. RxJS remains in HttpClient
The good side:
Makes it easy to design asycn patterns such as keeping one request per input
trigger (switchMap) or piping into other Rxjs operators
Which http calls should be made in parallel (`mergeMap`), cancel the one
ongoing and move to the new one (`switchMap`), make one after another has
finished (`concatMap`), etc etc.
The bad side:
Setting up streams for one-time ajax calls
40. RxJS Interop - takeUntilDestroy
It is very common to tie the lifecycle of an Observable to a
particular component’s lifecycle
// Here is a common Angular pattern:
destroyed$ = new ReplaySubject<void>(1)
data$ = http.get('...').pipe(takeUntil(this.destroyed$))
ngOnDestroy() {
this.destroyed$.next()
}
// Now, we can:
data$ = http.get('…').pipe(takeUntilDestroyed())
41. RxJS Interop
Convert a signal to observable:
import { toObservable, signal } from '@angular/core/rxjs-interop'
@Component({ ...})
export class App {
count_ = signal(0)
count$ = toObservable(this.count_)
ngOnInit() {
this.count$.subscribe(() => ...)
}
}
42. RxJS Interop
Convert an observable to a signal:
import { toSignal } from '@angular/core/rxjs-interop'
@Component({
template: `
<li *ngFor="let row of data_()"> {{ row }} </li>
`
})
export class App {
dataService = inject(DataService)
data_ = toSignal(this.dataService.data$, [])
}
Promise => Observable => Signal someone?
43. Simple counter signal
Here is a simple counter signal
@Component({
template: `
<div>Count: {{ count_() }}</div>
<div>Double: {{ doubleCount_() }}</div>
`
})
export class App {
count_ = signal(0)
doubleCount_ = computed(() => this.count_() * 2)
constructor() {
setInterval(() => this.count_.set(this.count_() + 1), 1000)
}
}
44. Simple RxJS counter
import { BehaviorSubject, map, take } from 'rxjs'
export class AppComponent {
template: `
<div>Count: {{ count$ | async }}</div>
<div>Double: {{ doubledCount$ | async }}</div>
`,
count$ = timer(0, 1000)
doubleCount$ = this.count$.pipe(map((v) => v * 2))
}
Here is a simple counter with RxJS:
45. RxJS is hard for humans
RxJS has a still learning curve, some developers would code it like that:
import { BehaviorSubject, map, take } from 'rxjs'
@Component({
selector: 'counter',
template: `
<div>Count: {{ count$ | async }}</div>
<div>Double: {{ doubleCount$ | async }}</div>
`
})
export class AppComponent {
count$ = new BehaviorSubject(0)
doubleCount$ = this.count$.pipe(map((value) => value * 2))
constructor() {
setInterval(() => {
let currentCount = 0
this.count$.pipe(take(1)).subscribe((x) => (currentCount = x))
this.count$.next(currentCount + 1)
}, 1000)
}
}
46. The downfall of Rxjs
• "Angular does not internally use RxJS to
propagate state or drive rendering in any
way.
• Angular only uses RxJS as a convenient
EventEmitter completely disconnected from
the change detection and rendering system"
• Amm.. what about async pipes?..
47. The downfall of Rxjs
RxJS is not glitch-free - It's easy to craft an example which shows this behavior:
import { BehaviorSubject, combineLatest, map } from 'rxjs'
const counter$ = new BehaviorSubject(0)
const isEven$ = counter$.pipe(map((value) => value % 2 === 0))
const message$ = combineLatest(
[counter$, isEven$],
(counter, isEven) => `${counter} is ${isEven ? 'even' : 'odd'}`
)
message$.subscribe(console.log)
counter$.next(1)
// 0 is even
// 1 is even ???
// 1 is odd
In asynchronous RxJS code, glitches are not typically an
issue because async operations naturally resolve at
different times.
Most template operations, however, are synchronous, and
inconsistent intermediate results can have drastic
consequences for the UI.
For example, an NgIf may become true before the data is
actually ready
48. The downfall of Rxjs
"Signals replace the currently used BehaviorSubject
With Signals, Subscriptions get created and destroyed
automatically under the hood. More or less what happens
using the async pipe in RxJS.
However, unlike Observables, Signals don’t require a
Subscription to be used outside the template."
49. The downfall of Rxjs
"Using the async pipe several times creates separate
Subscriptions and separate HTTP requests.
Developers need to be conscious about using a
shareReplay or avoid multiple subscribers to avoid
multiple calls and side effects.
50. The downfall of Immutability
"Signals work with both, we don't want to "pick sides" but
rather let developers choose the approach that works
best for their teams and use-cases.
52. Model inputs and two-ways-data-binding
@Component({
signals: true,
selector: 'some-checkbox',
template: `
<p>Checked: {{ checked() }}</p>
<button (click)="toggle()">Toggle</button>
`,
})
export class SomeCheckbox {
// Create a *writable* signal.
checked_ = model(false)
toggle() {
checked_.update(c => !c)
}
}
53. Model inputs and two-ways-data-binding
@Component({
signals: true,
selector: 'some-page',
template: `
<!-- Note that the getter is *not* called here,
the raw signal is passed -->
<some-checkbox [(checked)]="isAdmin_" />
`,
})
export class SomePage {
isAdmin_ = signal(false)
}
56. Life cycle hooks
• Zone-based components support eight different lifecycle
methods.
• Many of these methods are tightly coupled to the current
change detection model, and don't make sense for signal-
based components.
• Signal-based components will retain the following lifecycle
methods:
• ngOnInit
• ngOnDestroy
57. Life cycle hooks
To supplement signal components, three new
application-level lifecycle hooks:
function afterNextRender(fn: () => void): void
function afterRender(fn: () => void): {destroy(): void}
function afterRenderEffect(fn: () => void): {destroy(): void}
* Why not ChangeDetectionStrategy.Signals?..
58. Life cycle hooks
Here is an example:
@Component({
template: `
<p #p>{{ longText_() }}</p>
`,
})
export class AfterRenderCmp {
constructor() {
afterNextRender(() => {
console.log('text height: ' + p_().nativeElement.scrollHeight)
})
}
p_ = viewQuery('p')
}
59. Is this another Angular rewrite?
Hmmm…. yes
The Angular team takes backwards compatibility seriously
But many things change in the surface API
Don’t rush: While many library developers will work on signal support
we gonna dance the semver for some time
Consider Microfrontends where applicable
60. • Available on demand coders
• Advanced web-techs training
• Consulting and workshops for leaders
Contact us:
admin@misterbit.co.il
https://www.misterbit.co.il
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