What's New In Angular 7? Let’s Introduce Angular 7 New Features!

Angular 7 being smaller, faster and easier to use and it will making developers life easier.  Now Angular 7 is released! This is a major release and expanding to the entire platform including-

1.      Core framework,

2.      Angular Material,

3.      CLI

Stay Informed – Angular 7 Interview Question and Answers

How to update to Angular 7?

For updating Angular 6 to Angular 7, you should use a command -

ng update @angular/cli @angular/core

For more detail click on link - https://update.angular.io/

Many  of new things are added in Angular 7 and also many of us will curious to know these new features and bug fixes.

Let’s introduce added and modified new features of Angular 7 -

1.      Added a new interface - UrlSegment[] to CanLoad interface

2.      Added a new interface -  DoBootstrap interface

3.      Angular 7 added a new compiler - Compatibility Compiler (ngcc)

4.      Introduce a new Pipe called - KeyValuePipe

5.      Angular 7 now supporting to TypeScript 2.9 and Added Virtual Scrolling and Drag & Drop

6.      Added a new elements features - enable Shadow DOM v1 and slots

7.      Added a new router features - warn if navigation triggered outside Angular zone

8.      Added a new mappings for ngfactory  and ngsummary files to their module names in AOT summary resolver.

9.      Added a new "original" placeholder value on extracted XMB

10. Added a new ability to recover from malformed URLs

11. Added a new compiler support dot (.) in import statements and also avoid a crash in ngc-wrapped

12. Update compiler to flatten nested template fns

Bug Fixes - There are some bug fixes are available.

1.      Now using performance.mark() instead of console.time()

2.      Upgrade to trigger $destroy event on upgraded component element

Bug fixes on the core -

1.      do not clear element content when using shadow dom

2.      size regression with closure compiler

3.      Add a new hostVars and support pure functions in host bindings

Bug fixes on elements -

1.      Added a new compiler dependency

2.      Added a new compiler to integration

Features -

Let’s start to talk about new features in details.

Angular 7 added a new compiler that is called Angular Compatibility Compiler (ngcc).

The ngcc Angular node_module compatibility compiler - The ngcc is a tool which "upgrades" node_module compiled with non-ivy ngc into ivy compliant format.

This compiler will convert node_modules compiled with Angular Compatibility Compiler (ngcc), into node_modules which appear to have been compiled with TSC compiler transformer (ngtsc) and this compiler conversions will allow such “legacy” packages to be used by the Ivy rendering engine.

TSC transformer which removes and converts @Pipe, @Component, @Directive and @NgModule to the corresponding definePipe, defineComponent, defineDirective and defineInjector.

UrlSegment Interface - 

UrlSegment interface represents a single URL segment and the constructor, properties, and methods look like below UrlSegment class i.e.

classUrlSegment {

constructor(path: string, parameters: {...})

path: string

parameters: {...}

toString(): string

}

The UrlSegment is a part of a URL between the two slashes and it contains a path and matrix parameters associated with the segment.

Example:

@Component({

templateUrl:'./user.component.html',

styleUrls: ['./user.component.css']

})

classUserComponent {

constructor(router: Router) {

consturlTree: UrlTree = router.parseUrl('/user;id=101');

consturlSGroup: UrlSegmentGroup = urlTree.root.children[PRIMARY_OUTLET];

consturlSegment: UrlSegment[] = urlSGroup.segments;

urlSegment[0].path; // It will returns 'user'

urlSegment[0].parameters; //It will returns {id: 101}

  }

}

Ivy -

The Ivy rendering engine is a new backwards-compatible Angular renderer main focused on -

1.      Speed Improvements

2.      Size Reduction

3.      Increased Flexibility

The template functions for creating dynamically views are no longer nested functions inside each other.

Now we use for loops that are nested inside other loops.

The following Example -

function AppComponent(rf: RenderFlags, ctx: AppComponent) {

    function ulTemplateFun(rf1: RenderFlags, ctx0: any) {

        function liTemplateFun(rf1: RenderFlags, ctx1: any) {...}

    }

}

No longer create multiple functions instances for loops that are nested inside other loops.

The following Example -

<ul *ngFor="let student of students">

    <li *ngFor="let subject of student'> {{ subject }} </li>

</ul>

DoBootstrap -

Angular 7 added a new lifecycle hook that is called ngDoBootstrap and an interface that is called DoBootstrap.

The following Example -

//ngDoBootstrap - Life-Cycle Hook Interface

class AppModule implements DoBootstrap {

    ngDoBootstrap(appRef: ApplicationRef) {

        appRef.bootstrap(AppComponent);

    }

}

Virtual Scrolling and Drag & Drop - Go to for detail with example

<h4>Virtual Scrolling Example -</h4>

<cdk-virtual-scroll-viewport class="viewport-section"  itemSize="100">

   <div class="item-section" *cdkVirtualFor="let item of scrollItems">Your Item Row{{item}}</div>

</cdk-virtual-scroll-viewport>

Important Notes About Angular 7 New Features :-

Most of the sites sharing below points but these are fake points. Someone made up fake release notes as a joke but developers/peoples started treating it like it was true.

A.       Splitting of @angular/core

B.      A new ng-compiler

C.      A new @angular/mine

D.      A new @aiStore

My goal is to help developers understand what's true and what's not. Please ignore above points (A,B,C,D),  if you learned from somewhere.