I'm using leaflet maps in conjunction with Svelte and have the problem that setting the className property of an Icon (L.Icon) that is used for a Marker (L.marker) doesn't have any effect. My code works fine without Svelte, so I assume that the source of the problem is the dynamic generation of a css class. My (abbreviated) code looks like this:
var myIcon = L.icon({
iconUrl: "./svg/My-Icon.svg",
iconSize: [48, 48],
iconAnchor: [24, 32],
className: "svgShadow",
});
...
marker = L.marker(
geoJsonPoint.geometry.coordinates.reverse(),
{
icon: myIcon ,
name: "Here is some text"
}).addTo(map);
<!-- Styles go at the bottom of the file with Svelte -->
<style type="text/css">
.svgShadow {
filter: drop-shadow(5px 5px 5px rgb(0 0 0 / 0.5));
}
</style>
Inspecting the element in the browser even shows that the class name is set for the img element contained in the marker, but it doesn't have any effect. Again, this works without Svelte in a static HTML page. With Svelte I can only find a dynamically generated css class containing the style definition for .svgShadow that isn't applied, but how can I make this work with leaflet and Svelte? Unfortunately I also can't set styles directly with the leaflet icon as only className is exposed.
Styles are scoped by default. If the elements are not created directly as part of the markup, they will not have the necessary classes that are added to the styles.
You can e.g. use :global(.svgShadow) { ... to circumvent this.
(Note that this of course will apply the the styles everywhere, even outside the current component.)
I'm using scoped CSS with https://github.com/gaoxiaoliangz/react-scoped-css and am trying to follow the following rules (besides others):
Scoped component CSS should only include styles that manipulate the "inside" of the component. E.g. manipulating padding, background-color etc. is fine whilst I try to stay away from manipulating stuff like margin, width, flex etc. from within the component CSS
Manipulating the "outside" of a component (margin, width, flex etc.) should only be done by "consuming" or parent components
This is rule is somewhat derived from some of the ideas behind BEM (and probably other CSS methodologies as well) and allows for a rather modular system where components can be used without "touching their outside" but letting the parent decide how their internal layouts etc. works.
Whilst this is all fine in theory, I don't really know how to best manipulate the "outside styles" of a component from the consuming code which is best shown with an example:
search-field.scoped.css (the component)
.input-field {
background: lightcoral;
}
search-field.tsx (the component)
import './search-field.scoped.css';
type SearchFieldProps = {
className: string;
};
export const SearchField = (props: SearchFieldProps) => {
return <input className={`input-field ${props.className}`} placeholder="Search text" />;
};
sidebar.scoped.css (the consumer)
.sidebar-search-field {
margin: 16px;
}
sidebar.tsx (the consumer)
import './sidebar.scoped.css';
// ...
export const Sidebar = () => {
return (
<SearchField className="sidebar-search-field" />
(/* ... */)
);
};
In the above example, the CSS from the class sidebar-search-field in sidebar.scoped.css is not applied because the class passed to SearchField is scoped to the Sidebar and the final selector .sidebar-search-field[data-sidebarhash] simply doesn't match as the input element of the SearchField (obviously) doesn't have the data attribute data-sidebarhash but data-searchfieldhash.
ATM, I tend to create wrapper elements in situations like this which works but is rather cumbersome & clutters the markdown unnecessarily:
// ...
export const Sidebar = () => {
return (
<div className="sidebar-search-field">
<SearchField />
</div>
(/* ... */)
);
};
Question
Is there any way to "style scoped CSS component from the outside"?
Ps.: I'm not sure if all the above also applies to scoped styles in Vue. If not, please let me know how it works there so that I can create a feature request in https://github.com/gaoxiaoliangz/react-scoped-css.
I have an application where I'm using Material UI and its theme provider (using JSS).
I'm now incorporating fullcalendar-react, which isn't really a fully fledged React library - it's just a thin React component wrapper around the original fullcalendar code.
That is to say, that I don't have access to things like render props to control how it styles its elements.
It does however, give you access to the DOM elements directly, via a callback that is called when it renders them (eg. the eventRender method).
Here's a basic demo sandbox.
Now what I'm wanting to do is make Full Calendar components (eg, the buttons) share the same look and feel as the rest of my application.
One way to do this, is that I could manually override all of the styles by looking at the class names it's using and implementing the style accordingly.
Or - I could implement a Bootstrap theme - as suggested in their documentation.
But the problem with either of these solutions, is that that:
It would be a lot of work
I would have synchronisation problems, if I made changes to my MUI theme and forgot to update the calendar theme they would look different.
What I would like to do is either:
Magically convert the MUI theme to a Bootstrap theme.
Or create a mapping between MUI class names and the calendar class names, something like:
.fc-button = .MuiButtonBase-root.MuiButton-root.MuiButton-contained
.fc-button-primary= .MuiButton-containedPrimary
I wouldn't mind having to massage the selectors etc to make it work (ie. For example - MUI Buttons have two internal spans, whereas Full Calendar have just one). It's mostly about when I change the theme - don't want to have to change it in two places.
Using something like Sass with its #extend syntax would is what I have in mind. I could create the full-calendar CSS with Sass easily enough - but how would Sass get access to the MuiTheme?
Perhaps I could take the opposite approach - tell MUI 'Hey these class names here should be styled like these MUI classes'.
Any concrete suggestions on how I would solve this?
Here is my suggestion (obviously, it's not straight forward). Take the styles from the MUI theme and generate style tag based on it using react-helmet. To do it event nicely, I created a "wrapper" component that do the map. I implemented only the primary rule but it can be extended to all the others.
This way, any change you will do in the theme will affect the mapped selectors too.
import React from "react";
import { Helmet } from "react-helmet";
export function MuiAdapter({ theme }) {
if (!theme.palette) {
return <></>;
}
return (
<Helmet>
<style type="text/css">{`
.fc-button-primary {
background: ${theme.palette.primary.main}
}
/* more styles go here */
`}</style>
</Helmet>
);
}
And the use of the adapter
<MuiAdapter theme={theme} />
Working demo: https://codesandbox.io/s/reverent-mccarthy-3o856
You could create a mapping between MUI class names and the calendar class names by going through ref's. It's possible that this is not what some would call "best practice"...but it's a solution :). Note that I updated your component from a functional component to a class component, but you could accomplish this with hooks in a functional component.
Add refs
Add a ref to the MUI element you want to set as a reference, in your case the Button.
<Button
color="primary"
variant="contained"
ref={x => {
this.primaryBtn = x;
}}
>
And a ref to a wrapping div around the component you want to map to. You can't add it directly to the component since that wouldn't give us access to children.
<div
ref={x => {
this.fullCal = x;
}}
>
<FullCalendar
...
/>
</div>
Map classes
From componentDidMount() add whatever logic you need to target the correct DOM node (for your case, I added logic for type and matchingClass). Then run that logic on all FullCalendar DOM nodes and replace the classList on any that match.
componentDidMount() {
this.updatePrimaryBtns();
}
updatePrimaryBtns = () => {
const children = Array.from(this.fullCal.children);
// Options
const type = "BUTTON";
const matchingClass = "fc-button-primary";
this.mapClassToElem(children, type, matchingClass);
};
mapClassToElem = (arr, type, matchingClass) => {
arr.forEach(elem => {
const { tagName, classList } = elem;
// Check for match
if (tagName === type && Array.from(classList).includes(matchingClass)) {
elem.classList = this.primaryBtn.classList.value;
}
// Run on any children
const next = elem.children;
if (next.length > 0) {
this.mapClassToElem(Array.from(next), type, matchingClass);
}
});
};
This is maybe a little heavy handed, but it meets your future proof requirement for when you updated update Material UI. It would also allow you to alter the classList as you pass it to an element, which has obvious benefits.
Caveats
If the 'mapped-to' component (FullCalendar) updated classes on the elements you target (like if it added .is-selected to a current button) or adds new buttons after mounting then you'd have to figure out a way to track the relevant changes and rerun the logic.
I should also mention that (obviously) altering classes might have unintended consequences like a breaking UI and you'll have to figure out how to fix them.
Here's the working sandbox: https://codesandbox.io/s/determined-frog-3loyf
I have two routes on my React app: /a and /b.
For /a, I want the body css tag to have a background-color: red;.
For /b, I want the body css tag to have a background-color: blue;.
Both components a and b live in different .JSX files, and both import their own main.scss file which defines their own respective body background-color.
However, since the entire app is compiled into the body tag, there seems to be a conflict, and only one of the body tags is respected for both routes.
<body>
<script src="bundle.js" type="text/javascript"></script>
</body>
The reason I want it on the body tag and not just a container div is that I want the background-color to be visible when I scroll outside the bounds of the page (the bounce effect on Mac and iOS).
What's the proper way to do this?
That's happening because when you import your styles in your component without CSS Modules, the styles are global so your body style is defined two times (you can see all the styles in the <head> tag).
You can fix that by setting the background color in your component componentDidMount() method.
Example
componentDidMount(){
document.body.style.backgroundColor = "red"// Set the style
document.body.className="body-component-a" // Or set the class
}
or, if youre using functional components you can do the same with useEffect...
useEffect(() => {
document.body.className = 'class-name';
}, []);
I agree with what QoP said but, as an add on to that, you should also make sure to use componentWillUnmount to set it back to whatever it normally is outside that component.
for example:
if normally for the whole application text-align is left but for one component you want it to be center, but after the component it needs to return to being left, you will do the following:
componentDidMount() {
document.body.style.textAlign = "center"
}
componentWillUnmount(){
document.body.style.textAlign = "left"
}
Add this code
componentDidMount(){
document.body.style.backgroundColor = "white"
}
Hope to help.
Q1. Suppose I want to alter the look of each "item" that a user marks for deletion before the main "delete" button is pressed. (This immediate visual feedback should eliminate the need for the proverbial "are you sure?" dialog box.) The user will check checkboxes to indicate which items should be deleted. If a checkbox is unchecked, that item should revert back to its normal look.
What's the best way to apply or remove the CSS styling?
Q2. Suppose I want to allow each user to personalize how my site is presented. E.g., select from a fixed set of font sizes, allow user-definable foreground and background colors, etc.
What's the best way to apply the CSS styling the user selects/inputs?
Angular provides a number of built-in directives for manipulating CSS styling conditionally/dynamically:
ng-class - use when the set of CSS styles is static/known ahead of time
ng-style - use when you can't define a CSS class because the style values may change dynamically. Think programmable control of the style values.
ng-show and ng-hide - use if you only need to show or hide something (modifies CSS)
ng-if - new in version 1.1.5, use instead of the more verbose ng-switch if you only need to check for a single condition (modifies DOM)
ng-switch - use instead of using several mutually exclusive ng-shows (modifies DOM)
ng-disabled and ng-readonly - use to restrict form element behavior
ng-animate - new in version 1.1.4, use to add CSS3 transitions/animations
The normal "Angular way" involves tying a model/scope property to a UI element that will accept user input/manipulation (i.e., use ng-model), and then associating that model property to one of the built-in directives mentioned above.
When the user changes the UI, Angular will automatically update the associated elements on the page.
Q1 sounds like a good case for ng-class -- the CSS styling can be captured in a class.
ng-class accepts an "expression" that must evaluate to one of the following:
a string of space-delimited class names
an array of class names
a map/object of class names to boolean values
Assuming your items are displayed using ng-repeat over some array model, and that when the checkbox for an item is checked you want to apply the pending-delete class:
<div ng-repeat="item in items" ng-class="{'pending-delete': item.checked}">
... HTML to display the item ...
<input type="checkbox" ng-model="item.checked">
</div>
Above, we used ng-class expression type #3 - a map/object of class names to boolean values.
Q2 sounds like a good case for ng-style -- the CSS styling is dynamic, so we can't define a class for this.
ng-style accepts an "expression" that must evaluate to:
an map/object of CSS style names to CSS values
For a contrived example, suppose the user can type in a color name into a texbox for the background color (a jQuery color picker would be much nicer):
<div class="main-body" ng-style="{color: myColor}">
...
<input type="text" ng-model="myColor" placeholder="enter a color name">
Fiddle for both of the above.
The fiddle also contains an example of ng-show and ng-hide. If a checkbox is checked, in addition to the background-color turning pink, some text is shown. If 'red' is entered in the textbox, a div becomes hidden.
I have found problems when applying classes inside table elements when I had one class already applied to the whole table (for example, a color applied to the odd rows <myClass tbody tr:nth-child(even) td>). It seems that when you inspect the element with Developer Tools, the element.style has no style assigned. So instead of using ng-class, I have tried using ng-style, and in this case, the new CSS attribute does appear inside element.style. This code works great for me:
<tr ng-repeat="element in collection">
[...amazing code...]
<td ng-style="myvar === 0 && {'background-color': 'red'} ||
myvar === 1 && {'background-color': 'green'} ||
myvar === 2 && {'background-color': 'yellow'}">{{ myvar }}</td>
[...more amazing code...]
</tr>
Myvar is what I am evaluating, and in each case I apply a style to each <td> depending on myvar value, that overwrites the current style applied by the CSS class for the whole table.
UPDATE
If you want to apply a class to the table for example, when visiting a page or in other cases, you can use this structure:
<li ng-class="{ active: isActive('/route_a') || isActive('/route_b')}">
Basically, what we need to activate a ng-class is the class to apply and a true or false statement. True applies the class and false doesn't. So here we have two checks of the route of the page and an OR between them, so if we are in /route_a OR we are in route_b, the active class will be applied.
This works just having a logic function on the right that returns true or false.
So in the first example, ng-style is conditioned by three statements. If all of them are false, no style is applied, but following our logic, at least one is going to be applied, so, the logic expression will check which variable comparison is true and because a non empty array is always true, that will left an array as return and with only one true, considering we are using OR for the whole response, the style remaining will be applied.
By the way, I forgot to give you the function isActive():
$rootScope.isActive = function(viewLocation) {
return viewLocation === $location.path();
};
NEW UPDATE
Here you have something I find really useful. When you need to apply a class depending on the value of a variable, for example, an icon depending on the contents of the div, you can use the following code (very useful in ng-repeat):
<i class="fa" ng-class="{ 'fa-github' : type === 0,
'fa-linkedin' : type === 1,
'fa-skype' : type === 2,
'fa-google' : type === 3 }"></i>
Icons from Font Awesome
This works well when ng-class can't be used (for example when styling SVG):
ng-attr-class="{{someBoolean && 'class-when-true' || 'class-when-false' }}"
(I think you need to be on latest unstable Angular to use ng-attr-, I'm currently on 1.1.4)
I have published an article on working with AngularJS+SVG. It talks about this issue and numerous others. http://www.codeproject.com/Articles/709340/Implementing-a-Flowchart-with-SVG-and-AngularJS
span class="circle circle-{{selectcss(document.Extension)}}">
and code
$scope.selectcss = function (data) {
if (data == '.pdf')
return 'circle circle-pdf';
else
return 'circle circle-small';
};
css
.circle-pdf {
width: 24px;
height: 24px;
font-size: 16px;
font-weight: 700;
padding-top: 3px;
-webkit-border-radius: 12px;
-moz-border-radius: 12px;
border-radius: 12px;
background-image: url(images/pdf_icon32.png);
}
This solution did the trick for me
<a ng-style="{true: {paddingLeft: '25px'}, false: {}}[deleteTriggered]">...</a>
You can use ternary expression. There are two ways to do this:
<div ng-style="myVariable > 100 ? {'color': 'red'} : {'color': 'blue'}"></div>
or...
<div ng-style="{'color': (myVariable > 100) ? 'red' : 'blue' }"></div>
Another option when you need a simple css style of one or two properties:
View:
<tr ng-repeat="element in collection">
[...amazing code...]
<td ng-style="{'background-color': getTrColor(element.myvar)}">
{{ element.myvar }}
</td>
[...more amazing code...]
</tr>
Controller:
$scope.getTrColor = function (colorIndex) {
switch(colorIndex){
case 0: return 'red';
case 1: return 'green';
default: return 'yellow';
}
};
See the following example
<!DOCTYPE html>
<html ng-app>
<head>
<title>Demo Changing CSS Classes Conditionally with Angular</title>
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.0.7/angular.min.js"></script>
<script src="res/js/controllers.js"></script>
<style>
.checkboxList {
border:1px solid #000;
background-color:#fff;
color:#000;
width:300px;
height: 100px;
overflow-y: scroll;
}
.uncheckedClass {
background-color:#eeeeee;
color:black;
}
.checkedClass {
background-color:#3ab44a;
color:white;
}
</style>
</head>
<body ng-controller="TeamListCtrl">
<b>Teams</b>
<div id="teamCheckboxList" class="checkboxList">
<div class="uncheckedClass" ng-repeat="team in teams" ng-class="{'checkedClass': team.isChecked, 'uncheckedClass': !team.isChecked}">
<label>
<input type="checkbox" ng-model="team.isChecked" />
<span>{{team.name}}</span>
</label>
</div>
</div>
</body>
</html>
As of AngularJS v1.2.0rc, ng-class and even ng-attr-class fail with SVG elements (They did work earlier, even with normal binding inside the class attribute)
Specifically, none of these work now:
ng-class="current==this_element?'active':' ' "
ng-attr-class="{{current==this_element?'active':' '}}"
class="class1 class2 .... {{current==this_element?'active':''}}"
As a workaround, I've to use
ng-attr-otherAttr="{{current==this_element?'active':''}}"
and then style using
[otherAttr='active'] {
... styles ...
}
One more (in the future) way to conditionally apply style is by conditionally creating scoped style
<style scoped type="text/css" ng-if="...">
</style>
But nowadays only FireFox supports scoped styles.
There is one more option that I recently discovered that some people may find useful because it allows you to change a CSS rule within a style element - thus avoiding the need for repeated use of an angular directive such as ng-style, ng-class, ng-show, ng-hide, ng-animate, and others.
This option makes use of a service with service variables which are set by a controller and watched by an attribute-directive I call "custom-style". This strategy could be used in many different ways, and I attempted to provide some general guidance with this fiddle.
var app = angular.module('myApp', ['ui.bootstrap']);
app.service('MainService', function(){
var vm = this;
});
app.controller('MainCtrl', function(MainService){
var vm = this;
vm.ms = MainService;
});
app.directive('customStyle', function(MainService){
return {
restrict : 'A',
link : function(scope, element, attr){
var style = angular.element('<style></style>');
element.append(style);
scope.$watch(function(){ return MainService.theme; },
function(){
var css = '';
angular.forEach(MainService.theme, function(selector, key){
angular.forEach(MainService.theme[key], function(val, k){
css += key + ' { '+k+' : '+val+'} ';
});
});
style.html(css);
}, true);
}
};
});
well i would suggest you to check condition in your controller with a function returning true or false .
<div class="week-wrap" ng-class="{today: getTodayForHighLight(todayDate, day.date)}">{{day.date}}</div>
and in your controller check the condition
$scope.getTodayForHighLight = function(today, date){
return (today == date);
}
One thing to watch is - if the CSS style has dashes - you must remove them. So if you want to set background-color, the correct way is:
ng-style="{backgroundColor:myColor}"
Here's how i conditionally applied gray text style on a disabled button
import { Component } from '#angular/core';
#Component({
selector: 'my-app',
styleUrls: [ './app.component.css' ],
template: `
<button
(click)='buttonClick1()'
[disabled] = "btnDisabled"
[ngStyle]="{'color': (btnDisabled)? 'gray': 'black'}">
{{btnText}}
</button>`
})
export class AppComponent {
name = 'Angular';
btnText = 'Click me';
btnDisabled = false;
buttonClick1() {
this.btnDisabled = true;
this.btnText = 'you clicked me';
setTimeout(() => {
this.btnText = 'click me again';
this.btnDisabled = false
}, 5000);
}
}
Here's a working example:
https://stackblitz.com/edit/example-conditional-disable-button?file=src%2Fapp%2Fapp.component.html