As angular official documentation says, ::ng-deep , >>>, /deep/ is deprecated and will be removed soon:
https://angular.io/guide/component-styles#deprecated-deep--and-ng-deep
If i am using mat components like <mat-checkbox> or a more comprehensive one like <mat-table> how could I have some changes to that component from parent?
Should I cancel view encapsulation for that component and write
styles in .SCSS files?
How do I edit styles of inner material angular component if deep selector is going to be removed?
What is the proper way to do that?
As the mention document says you can use the combination of ::ng-deep with :host and it will be OK in this way.
In order to scope the specified style to the current component and all its descendants, be sure to include the :host selector before ::ng-deep. If the ::ng-deep combinator is used without the :host pseudo-class selector, the style can bleed into other components
:host /deep/ h3 {
font-style: italic;
}
But, you also can use the custom CSS class & id to apply your custom css on .CSS or .SCSS files on the Angular Material Components. using .class & #id in combination with mat default classes works.
In addition you can use custom Angular material classes in your componnent style files ( .CSS or .SCSS) to override the like this:
.app-component-style {
/* All the CSS here */
.mat-tab-group .mat-tab-label {color: green;}
}
So, keep using it as Dudewad mention here too:
https://stackoverflow.com/a/49308475/4185370
Related
Im using angular material stepper. I need set padding 0 on mobile view.On developer console i could set padding 0 by changing .mat-horizontal-content-container. But its not working when i add .mat-horizontal-content-container{padding:0 !important;}Is there any solution to this problem?
You need to use the ::ng-deep pseudo selector, see https://blog.angular-university.io/angular-host-context/#thengdeeppseudoclassselector
:host ::ng-deep .mat-horizontal-content-container {
padding:0 !important;
}
Material elements are not part of the HTML structure of your component.
To access them in your SCSS ( CSS etc. ) you can use ng-deep which is a shadow-piercing descendant combinator that let's you access html elements which are not part of your component structure.
ng-deep angular doc
::ng-deep .mat-horizontal-content-container {padding:0 !important;}
BUT This combinator is deprecated ( as you can read in the docs ). THere is another way you can accomplish what you want but it's not really ideal. This is with using the ViewEncapsulation
#Component({
template: 'component.html',
selector: 'app-component-name',
styles: 'component.style.scss',
encapsulation: ViewEncapsulation.None
})
None means that Angular does no view encapsulation. Angular adds the CSS to the global styles. The scoping rules, isolations, and protections discussed earlier don't apply. This is essentially the same as pasting the component's styles into the HTML.
That being said, for now, ::ng-deep should be the way to go in these cases until it will be dropped by Angular. Because as the doc states :
As such we plan to drop support in Angular (for all 3 of /deep/, >>> and ::ng-deep). Until then ::ng-deep should be preferred for a broader compatibility with the tools.
In my angular 6 app. There are many components I have created. For display data I have used ng2-smart-table.
I have some specific requirement to hide default pagination bar. And display custom pagination.
For that I have just set css in component's SCSS file.
::ng-deep .ng2-smart-pagination-nav {
display: none
}
But this is also affects in all other components also.
Till I know and RND on that, In angular we used each component has their each scss file. So my question is why this css affect to all other component also? And how to prevent in this issue ?
The /deep/ combinator works to any depth of nested components, and it
applies to both the view children and content children of the
component
Use
:host Use the :host pseudo-class selector to target styles in the
element that hosts the component (as opposed to targeting elements
inside the component's template).
:host ::ng-deep .ng2-smart-pagination-nav {
display: none
}
I have a couple Angular components that route back and forth to one another. They both have mat-form-field's. In one component, I am overriding the styling of the underline component like so:
::ng-deep .mat-input-underline {
display: none;
}
When I click on the link to go back to the other component, the styling as defined as above carries over and the underline components are gone. I tried to add styling like:
::ng-deep .mat-input-underline {
display: revert;
//or
display: unset;
//or
display: initial;
}
But none of them work. How can I override the material design styling on just one component but not the others?
Your issue is caused by ::ng-deep, which will apply style to all .mat-input.underline elements in the page once the component has been loaded and style injected.
If you really want to keep the ::ng-deep combinator, you can add the :host selector to prefix your rule, which will target the host element and not leak the css to other components (apart from child components)
:host ::ng-deep .mat-input-underline
{
display: none;
}
https://angular.io/guide/component-styles#host
Style your component this way, this styling would not leak to the child component. Use ::ng-deep within :host but exactly like I have done below.
:host {
::ng-deep p, .py-8 {
margin: 0 !important;
}
}
I'm assuming you are using Angular Cli to generate your components...
You need to Emulate the encapsulation property on your Component. Although Angular defaults to 'Emulate'. (Thanks David, for correcting me).
In a nutshell, Emulated allows your component to make use of global styles, while keeping its local styles to itself.
#Component({
selector: 'app-child-component',
template: `<div class="parent-class">Child Component</div>`,
encapsulation: ViewEncapsulation.Emulated
})
Also, ::ng-deep is meant to pass styles from parents to children. So if you are trying to keep your child elements from adopting the styles of their parents, using that is working against you.
"/deep/" is deprecated and "::ng-deep" is the way but be careful.
Please go through below official documentation for detailed information.
https://angular.io/guide/component-styles#deprecated-deep--and-ng-deep
How and where can one use ::ng-deep in Angular 4?
Actually I want to overwrite some of the CSS properties of the child components from the parent components. Moreover is it supported on IE11?
Usually /deep/ “shadow-piercing” combinator can be used to force a style down to child components. This selector had an alias >>> and now has another one called ::ng-deep.
since /deep/ combinator has been deprecated, it is recommended to use ::ng-deep
For example:
<div class="overview tab-pane" id="overview" role="tabpanel" [innerHTML]="project?.getContent( 'DETAILS')"></div>
and css
.overview {
::ng-deep {
p {
&:last-child {
margin-bottom: 0;
}
}
}
}
it will be applied to child components
I would emphasize the importance of limiting the ::ng-deep to only children of a component by requiring the parent to be an encapsulated css class.
For this to work it's important to use the ::ng-deep after the parent, not before otherwise it would apply to all the classes with the same name the moment the component is loaded.
Using the :host keyword before ::ng-deep will handle this automatically:
:host ::ng-deep .mat-checkbox-layout
Alternatively you can achieve the same behavior by adding a component scoped CSS class before the ::ng-deep keyword:
.my-component ::ng-deep .mat-checkbox-layout {
background-color: aqua;
}
Component template:
<h1 class="my-component">
<mat-checkbox ....></mat-checkbox>
</h1>
Resulting (Angular generated) css will then include the uniquely generated name and apply only to its own component instance:
.my-component[_ngcontent-c1] .mat-checkbox-layout {
background-color: aqua;
}
USAGE
::ng-deep, >>> and /deep/ disable view encapsulation for specific CSS rules, in other words, it gives you access to DOM elements, which are not in your component's HTML. For example, if you're using Angular Material (or any other third-party library like this), some generated elements are outside of your component's area (such as dialog) and you can't access those elements directly or using a regular CSS way. If you want to change the styles of those elements, you can use one of those three things, for example:
::ng-deep .mat-dialog {
/* styles here */
}
For now Angular team recommends making "deep" manipulations only with EMULATED view encapsulation.
DEPRECATION
"deep" manipulations are actually deprecated too, BUT it's still working for now, because Angular does pre-processing support (don't rush to refuse ::ng-deep today, take a look at deprecation practices first).
Anyway, before following this way, I recommend you to take a look at disabling view encapsulation approach (which is not ideal too, it allows your styles to leak into other components), but in some cases, it's a better way. If you decided to disable view encapsulation, it's strongly recommended to use specific classes to avoid CSS rules intersection, and finally, avoid a mess in your stylesheets. It's really easy to disable right in the component's .ts file:
#Component({
selector: '',
template: '',
styles: [''],
encapsulation: ViewEncapsulation.None // Use to disable CSS Encapsulation for this component
})
You can find more info about the view encapsulation in this article.
Make sure not to miss the explanation of :host-context which is directly above ::ng-deep in the angular guide : https://angular.io/guide/component-styles. I missed it up until now and wish I'd seen it sooner.
::ng-deep is often necessary when you didn't write the component and don't have access to its source, but :host-context can be a very useful option when you do.
For example I have a black <h1> header inside a component I designed, and I want the ability to change it to white when it's displayed on a dark themed background.
If I didn't have access to the source I may have to do this in the css for the parent:
.theme-dark widget-box ::ng-deep h1 { color: white; }
But instead with :host-context you can do this inside the component.
h1
{
color: black; // default color
:host-context(.theme-dark) &
{
color: white; // color for dark-theme
}
// OR set an attribute 'outside' with [attr.theme]="'dark'"
:host-context([theme='dark']) &
{
color: white; // color for dark-theme
}
}
This will look anywhere in the component chain for .theme-dark and apply the css to the h1 if found. This is a good alternative to relying too much on ::ng-deep which while often necessary is somewhat of an anti-pattern.
In this case the & is replaced by the h1 (that's how sass/scss works) so you can define your 'normal' and themed/alternative css right next to each other which is very handy.
Be careful to get the correct number of :. For ::ng-deep there are two and for :host-context only one.
Just an update:
You should use ::ng-deep instead of /deep/ which seems to be deprecated.
Per documentation:
The shadow-piercing descendant combinator is deprecated and support is
being removed from major browsers and tools. As such we plan to drop
support in Angular (for all 3 of /deep/, >>> and ::ng-deep). Until
then ::ng-deep should be preferred for a broader compatibility with
the tools.
You can find it here
I looked through all those answers and found nobody mentioned a child component can pass a style CSS in from its parent.
In component ts file, you can use this:
#Input() styles: any = {};
In component html file, you use this:
[ngStyle]="styles"
in parent, you use this :
<yourComponent [styles]="{backgroundColor: 'blue', 'font-size': '16px'}">
Please see more details here: Best way to pass styling to a component
In this way, we didn't break encapsulation, which is one of those most important Object orientation principles
Use ::ng-deep with caution. I used it throughout my app to set the material design toolbar color to different colors throughout my app only to find that when the app was in testing the toolbar colors step on each other. Come to find out it is because these styles becomes global, see this article Here is a working code solution that doesn't bleed into other components.
<mat-toolbar #subbar>
...
</mat-toolbar>
export class BypartSubBarComponent implements AfterViewInit {
#ViewChild('subbar', { static: false }) subbar: MatToolbar;
constructor(
private renderer: Renderer2) { }
ngAfterViewInit() {
this.renderer.setStyle(
this.subbar._elementRef.nativeElement, 'backgroundColor', 'red');
}
}
I was wondering how to override the encapsulated CSS of an external component.
So I am using material2 in my project and the tabs component has a the attribute overflow set on tab-body. Is it possible to override the overflow value?
You can use the special css /deep/ instruction. See the documentation
So, if you have
app
sub-component
target-component
<div class="target-class">...</div>
You can put in your apps css (or less):
/deep/ .target-class {
width: 20px;
background: #ff0000;
}
Obviously, you can put this css fragment in sub-component as well.
From this article
Although the style of a component is well isolated, it can still be easily overridden if necessary. For that, we just need to add an attribute to the body of the page:
<body override>
<app></app>
</body>
The name of the attribute can be anything. No value is needed and the name override makes it apparent what its being used for. To override component styles, we can then do the following:
[override] hello-world h1 {
color:red;
}
Where override is the attribute, hello-world is the target component, and h1 is whatever you are trying to restyle. (get this right or it wont work).
Your component hello-world would be
selector: 'hello-world',
styles: [`
h1 {
color: blue;
}
`],
template: ` <h1>Hello world</h1> `
I think this is the most elegant way.
Alternatively if you are building a library of some sort, you can reset the styling altogether by doing something fancy in your css like:
:host-context(.custom-styles) {
//.. css here will only apply when there is a css class custom-styles in any parent elem
}
So then to use your component you'd use
<hello-world class="custom-styles">
But this is way less convenient than the first option.
::ng-deep .tag-or-css-class-you-want-to-override {
/* Add your custom css property value. */
}
The syntax ::ng-deep is used to override outside css class or tags without using ViewEncapsulation.None.
I see variations of this question a lot and since this is the top question on the subject I want to give the simplest answer. ng-deep and similar functionality is deprecated, so it's best to just rely on vanilla CSS.
Simply create a CSS selector with a higher specificity.
Most people (including myself) get hung up trying to do that because they don't understand two things:
Angular View Encapsulation
CSS Specificity
Angular View Encapsulation
View Encapsulation ensures CSS within a component only affects that component. To affect other components, you need some global CSS. You can do this by using a global style file like styles.css or by disabling View Encapsulation on a component.
#Component({
...
encapsulation: ViewEncapsulation.None
})
CSS Specificity
When two selectors select the same element, the CSS that actually gets applied is based on specificity: https://developer.mozilla.org/en-US/docs/Web/CSS/Specificity
You can increase specificity by simply adding more elements to your CSS selector. For example p.className is more specific than just .className. If you're lazy, you can just repeat a class name to increase specificity. .className.className is more specific than .className.
So to override any CSS in an Angular project, go into styles.css and repeat the class selector until your CSS has a higher specificity than the original.
.className.className.className {
color: red;
}
Didn't work? Add another .className.
Just check the class that is being applied to the tabs by the external component (use Inspector or any other tool). In your style css file, add the same name of the class for the tabs and set the overflow property along with adding !important to it to make sure it overwrites the previous one. Also make sure your css link to the page is added after the external component css link if any.
Hope this helps.
::ng-deep .css-class-you-want-to-override{
/*your custom css property value. like below */
background: white !important;
}