I' m trying to use CSS in JAVAFX application. Is there a way in the CSS file to make use of some kind of inheritance?
For example I have one style called "redline":
.redline{
-fx-stroke:red;
-fx-stroke-width:5px;
}
Can I create a second style "greenline":
.greenline{
-fx-stroke:green;
}
in a way that it inherits from "redline". Say, something like:
greenline extends redline
so that the "green" lines have a strokewidth of 5px?
Thanks in advance!
You need to make a make a more specific selector available. You could e.g. add a style class:
Add the style class line to all lines and then also add the red or blue style classes to the lines that should get those colors.
Example
Java Code
Line redLine = ...
redLine.getStyleClass().add("line");
Line blueLine = ...
blueLine.getStyleClass().add("line");
Line blackLine = ...
blackLine.getStyleClass().add("line");
// add color related classes
redLine.getStyleClass().add("red");
blueLine.getStyleClass().add("blue");
...
CSS
.line {
-fx-stroke: black; /* define standard line color */
-fx-stroke-width: 5px;
}
.line.blue { /* rules for nodes that have style classes line AND blue */
-fx-stroke: blue;
}
.line.red { /* rules for nodes that have style classes line AND red */
-fx-stroke: red;
}
In CSS more specific rules will always overwrite properties of less specific rules. In this case .line is less specific than .line.blue and .line.red since the former selector contains only a single class instead of 2.
Note: There is inheritance in CSS, but properties are inherited from the parent in the scene, not from the base class in the java code.
Related
how do you apply a specific css to second-page
HTML
<div className = "section-header second-page">SOME MESSAGE</div>
Assuming the above:
CSS
.section-header {
background-color: black,
}
i want to apply a different background color specifically to second-page that does not modify section-header.
If you want the styling to apply to any element with .second-page class you should use:
.second-page {
backgound-color: red,
}
If you want the styling to apply only to .section-header elements that also have .second-page class, then you should use:
.section-header.second-page {
backgound-color: red,
}
When there's no space between two classes, it means it refers to an element with both classes.
For more information on CSS selectors, please check
https://www.w3schools.com/cssref/css_selectors.asp
Your HTML should be:
<div class="section-header second-page">SOME MESSAGE</div>
Your CSS could be:
.second-page {
background-color: black,
}
You can mix multiple classes within the HTML or target them separately.
If you need to validate your HTML code you can use this free service:
https://validator.w3.org/#validate_by_input
I use the following CSS to change the font of some components which are placed on a custom JavaFX AnchorPane, defined as fx:root. But the font-size remains default.
* {
-fx-font-family : Arial;
}
.label, .textField, .textfield, .checkBox, .text{
-fx-font-size: 18;
}
I got that I should change them using the ids of all inner components but it's not a good idea, because it results in redundant code.
Then I got that applying it on the main style class, it will work. But the sad story is that * can't be overriden. (I have defined * selector in a global css class for my whole application.
Try .root instead of *.
For the font size, some of your class names are wrong. Try
.label, .text-field, .check-box, .text {
-fx-font-size: 18pt ;
}
Style classes are documents in the CSS Reference Guide
Note that Text nodes have empty style class, so you need to explicitly set the style class for your text nodes.
I know CSS selector with the highest specificity takes precedence (i.e. .classname < #idname).
I also know that if things are the same specificity, then the last statement called takes precedence:
.classname1 { color: red; }
.classname1 { color: blue; } // classname1 color will be blue
Does the ordering of HTML classes on a DOM element affect the statement priority?
I have to disagree slightly with Jon and Watson's answers, as...
Yes, it Can (depending on the statement)
Your question is:
Does the ordering of CSS classes on a DOM element affect the statement priority?
Which does depend on the statement in question.
HTML Ordering Does Not Typically Matter
The following are equivalent when it comes to a straight call to a class (i.e. .class1 or .class2) or to a combined call (i.e. .class1.class2 or .class2.class1):
<div class="class1 class2"></div>
<div class="class2 class1"></div>
Cases Where Statement Priority for above HTML Can be Affected Based on HTML Order
The main place where ordering in HTML matters is with the use of attribute selectors in your CSS.
Example 1 Fiddle using the following code seeking to match attribute value will NOT have any change in font color, and each div will have different properties because of the ordering of the classes:
[class="class1"] {
color: red;
}
[class="class1 class2"] {
background-color: yellow;
}
[class="class2 class1"] {
border: 1px solid blue;
}
Example 2 Fiddle using the following code seeking to match beginning of attribute value will NOT have any change in font color for the second div, and each div will have different properties because of the ordering of the classes:
[class^="class1"] {
color: red;
}
[class^="class1 class2"] {
background-color: yellow;
}
[class^="class2 class1"] {
border: 1px solid blue;
}
Example 3 Fiddle using the following code seeking to match end of attribute value will NOT have any change in font color for the first div, and each div will have different properties because of the ordering of the classes:
[class$="class1"] {
color: red;
}
[class$="class1 class2"] {
background-color: yellow;
}
[class$="class2 class1"] {
border: 1px solid blue;
}
A Clarifying Statement about "Priority"
To be clear, in the cases above, what is affected as far as "statement priority" is concerned is really a matter of whether the statement actually applies or not to the element. But since the application or not is in a sense, the basic priority, and since the above are cases where such application is actually based on the ordering of the classes on the HTML Dom element (rather than the presence or absence of the class), I thought it worth adding this as an answer.
Possible Valid Use of Class Ordering?
This is a thought occurring to me, based on BoltClock's comment. Consider just two classes being used to style elements based on whatever factors are deemed critical to different styling. These two classes theoretically can replace the use of eleven different individual classes using the combination of attribute selectors (actually, as will be noted later, the possibilities are almost limitless with but a single class, but I'll discuss that in a moment since this post is about ordering of multiple classes). For these two classes we can style elements differently as follows:
Assuming these HTML Combinations
<div class="class1">Element 1</div>
<div class="class2">Element 2</div>
<div class="class1 class2">Element 3</div>
<div class="class2 class1">Element 4</div>
CSS Possibilities
/* simply has the class */
.class1 {} /* affects elements 1, 3, 4 */
.class2 {} /* affects elements 2-4 */
/* has only a single class */
[class="class1"] {} /* affects element 1 only */
[class="class2"] {} /* affects element 2 only */
/* simply has both classes */
.class1.class2 {} /* affects elements 3-4 */
/* has both classes, but in a particular order */
[class="class1 class2"] {} /* affects element 3 only */
[class="class2 class1"] {} /* affects element 4 only */
/* begins with a class */
[class^="class1"] {} /* affects elements 1 & 3 only */
[class^="class2"] {} /* affects elements 2 & 4 only */
/* ends with a class
NOTE: that with only two classes, this is the reverse of the above and is somewhat
superfluous; however, if a third class is introduced, then the beginning and ending
class combinations become more relevant.
*/
[class$="class1"] {} /* affects elements 2 & 4 only */
[class$="class2"] {} /* affects elements 1 & 3 only */
If I calculate right, 3 classes could give at least 40 combinations of selector options.
To clarify my note about "limitless" possibilities, given the right logic, a single class can potentially have imbedded in it code combinations that are looked for via the [attr*=value] syntax.
Is all this too complex to manage? Possibly. That may depend on the logic of exactly how it is implemented. The point I am trying to bring out is that it is possible with CSS3 to have ordering of classes be significant if one desired it and planned for it, and it might not be horribly wrong to be utilizing the power of CSS in that way.
No, it does not. The relevant part of the W3C standard makes no mention of the order of appearance for classes.
No, it does not, like you said, if two rules have the same specificity, the one that comes later in your CSS will be applied.
No. But if you want to make one of your declaration blocks to has more precedence (w/o many !importants) make its selector more specific.
For example, for a div:
div.classname1 { color: red; } /* classname1 color will be red (for `div`s) */
.classname1 { color: blue; }
What's missing or a little hard to find in other answers is this:
What matters is the order in which the browser reads/parses the class names
The class defined last will win
.a {
color: red;
}
.b {
color: blue;
}
<div class="a b">This text will be blue</div>
<div class="b a">This text will ALSO be blue</div>
Example comes from this source
May be affected by the order of your imports
Because if this you may need to pay attention to how you import CSS in your files.
For example in my JavaScript based project I have a component that I can pass extra classes to. In order for my own classes to overwrite styles of the classes of the component itself I need to first import the component I wish to style (which will import its own styles) and only then import my own styles:
//import the component first, which will import css
import {SomeComponent} from 'some-library/SomeComponent';
//And THEN our own styles
import './styles.css';
return <SomeComponent className={myClassName} />
Like this my buildprocess (Webpack) will put my own classes later in the CSS bundle than the components ones.
I am trying to make a specific column to blue color.
For that I am using
clientsTable.addColumnStyleName(3,"nameColumn");
And the CSS is:
nameColumn {
color:blue;
}
but it's not doing anything whereas if I change my CSS to this
nameColumn {
background-color:blue;
}
it works, i.e make header color red , but why is not changing text color ?
thanks
addColumnStyleName adds the CSS class to a <col> element in the DOM, and only a handful CSS properties apply there (see also browser compatibility table)
You'd want to apply a CSS class to each cell in the column instead, using Column#setCellStyleNames()
Try
.nameColumn {
color: blue !important;
}
I have a window with two buttons.
I'd like to decorate each one with a different stylesheet. They both have different object names, of course, but it seems that only the generic QPushButton stylesheet selector works.
I tried:
QPushButton#myBtnObjectName1 {
/* style definitions */
}
QPushButton#myBtnObjectName2 {
/* style definitions */
}
Tried the same with replacing the # with a ., or having the #myBtnObjetNameX only. Nothing works. Just:
QPushButton {
/* style definitions */
}
Am I using a wrong syntax? Or is this simply impossible without deriving from QPushButton in code and using a separate class name for each?
To match instances using the objectName, you can also use the selector ^=. According to the standard:
[att^=val] Represents an element with the att attribute whose value
begins with the prefix "val".
Example in Qt:
QPushButton[objectName^="push"] { background-color: red; }
A QPushButton called pushButton would be matched, but not an object called pbt.
You can use "accessibleName" in Qt Designer for this.
And in qss stylesheet:
more universal:
[accessibleName="alert-error"] {
color: red;
}
or be more specific:
QPushButton[accessibleName="bigred"] {
background-color: red;
}
Ah yes, the "AccessibleName" in Qt Designer needs to be set too, not just "ObjectName"