I am seeing an anchor tag with a data-folder attribute. What is this for? I researched it but found no info on it.
Also, I see that it has a data-toggle="dropdown" attribute. I researched that and see that it is a HTML 5 attribute used with the Bootstrap jQuery plugin (dropdown.js). So it's: data-toggle="dropdown".
Departments<span class=" caret"></span>
data-folder is custom made data-* attribute that later is used by some other tool, like CSS or JS/jQuery.
By the name of this attribute folder we can tell that it's indicating some reference to folder on server system (maybe ID of departments group?). Not knowing more about what you use we can't tell exactly.
If you are using one of supportable libraries (like jQuery), than you can use Visual Events to check what events does this specific element has.
This is a Custom Data Attribute as specified in W3C HTML5 specification.
Some libraries have methods developed around these type of attributes for easy storing and retrieval of data. Look at the JQuery .data method. This method retrieves/stores values via data attributes.
In your case the the following statement will return the value 4590.
$('<a>').data('folder')
Related
I have a doubt about good practices writing HTML with Javascript.
I've came up with an idea (probably not the first, but couldn't find a clear reference about that) to mark some elements as candidates to load some data when it's available (after some user interaction). Let me exemplify:
Suppose I have a request that returns the following:
GET /animals/dog
{
name: "Gutemberg",
race: "doberman",
age: "2y"
}
The code I wrote binds fields in the response to elements that are candidates to load such value.
For example: With the request above, I could use the following tags:
<input name="dog-name-field" data-load-dog-name type="text"/>
<input name="dog-age-hid" data-load-dog-age type="hidden"/>
Each tag would receive the property value because it's marked as a candidate to do so - dog-name-field will have a value of "Gutemberg" when everything executes . That will happen everytime the request is reloaded. For now, I just get the data type I've searched ("dog"), concat it with the property "name/age" to form the attribute data-load-type-property and set a value to everyone that has such attribute.
I have a feeling that attributes are not meant to be used just like that, but I'm not aware of any real downsides to that. As I could not find it for the lack of a clear name to this approach, I'd like some guidance.
Is there a name for such technique? Is it a bad practice? If so, why?
PS:
To comply with SO good practices, I'd like the answers to be reference-guided and not based solely on opinion whenever possible. If no reference is provided, please, let us have a solid, well described example.
I have a feeling that attributes are not meant to be used just like that
Let's see what custom data attributes are meant to be used for:
Custom data attributes are intended to store custom data private to
the page or application, for which there are no more appropriate
attributes or elements. These attributes are not intended for use by
software that is independent of the site that uses the attributes.
(from w3.org)
So whether using data-attributes is "appropriate" in your case depends on your needs: if the DOM API doesn't provide better attributes to do that then it's appropriate.
If your need is just to select some element to change the textContent then you have two more appropriate/simpler options:
1) Using the id attribute if your elements are going to be unique in the document
The id global attribute defines a unique identifier (ID) which must be
unique in the whole document. Its purpose is to identify the element
when linking (using a fragment identifier), scripting, or styling
(with CSS).
(from id on MDN)
2) Using the class attribute if your elements are going to be used in multiple instances in the document
The class global attribute is a space-separated list of the classes of
the element. Classes allows CSS and Javascript to select and access
specific elements via the class selectors or functions like the DOM
method document.getElementsByClassName.
(from class on MDN)
As #Supr says in his answer, what you are doing is a very simple implementation of data-binding. data-binding can involve a lot more complexity than what you are doing at the moment; for example you may want to:
keep in sync your UI with a Javascript object which represent your business model instead of directly injecting data coming from an Ajax call,
update other attributes (value, style) and not only innerHTML or textContent,
have your business model updated in reaction to changes on the UI (two way data binding)
To implement all these features, simple id and class selectors are not sufficient, and this is why frameworks which implement data-binding, like KnockoutJS or AngularJS, use the more flexible data-* attributes instead (AngularJS is actually using its own ng-* attributes, but allows to use the alternative data-ng-* syntax for using HTML validation tools).
Data attributes allow to describe much more complex bindings:
<input data-bind="visible: editing, value: name, hasFocus: editing" />
Check KnockoutJS documentation for the meaning of the above code, it is not relevant to this example but just imagine describing that with classes or ids, it wouldn't be very convenient.
TL;DR
If you don't plan to implement more complex features you might want to use class and id instead.
This is called binding. Sometimes data binding and sometimes template binding.
Various frameworks provide mechanisms for this, though the syntax varies.
AngularJS example:
<input ng-model="dog.name" />
Knockout example:
<input data-bind="textInput: dog.name" />
React example:
<input value={this.state.dog.name} />
These are all quite popular frameworks/libraries, so I think it's safe to say it is not considered bad practice. The main difference from your approach is that they use the value of the attribute to specify the reference into the model (i.e. the "dog.name" part of your attributes), while you are putting the reference in the attribute name. In practice this is mostly a matter of style. Separating the reference from the "marker" (i.e. "data-load") is perhaps a bit more readable.
I have an control, to which I want to add a custom html attribute called, previousValue.
The Salesforce Developer's Guide assures me that I can do this by prefixing the attribute name with html-.
So I have an element that appears thus:. I also have the docType="html-5.0" attribute in my page control.
However, in Eclipse I get an 'unsupported attribute' error. I have upgraded to the latest force.com IDE; can any one tell me why this isn't working? What else do I need to do?
Thanks.
After much experimentation, the answer to this seems to be that the salesforce developer's guide is inaccurate and the 'hmtl-' prefix is not supported by the <apex:inputField> component. I can add it without a problem to an <apex:outputPanel> component. Don't understand why this should be so and the whole point to using these attributes is to locate data in a relevant place and avoid complex jquery selects to find the data relative to the location at which it is required.
I recently downloaded a code and it shows
<button data-effect="st-effect-4">Slide along</button>
From what I figured out "st-effect-4" is a class name but can anyone tell me what this data-effect is for?
HTML5 allows for custom attributes, as long as they begin with "data-". This is a custom attribute with a specific value.
Those are called HTML5 Custom Data attributes.
Custom data attributes are intended to store custom data private to
the page or application, for which there are no more appropriate
attributes or elements. These attributes are not intended for use by
software that is independent of the site that uses the attributes.
Every HTML element may have any number of custom data attributes
specified, with any value.
The reason why you can't find it in Google is because those attribute are custom attributes generated by user for there own use.
It's not for anything.
HTML5 specifies that (just about) any element can have any "data-*" attributes it wants, which can hold any values they want (as long as they can be treated like strings, to store on the element).
So that might be part of a library, or it might just be somebody's CSS for a selector like:
button[data-effect] { background : blue; }
button[data-effect="st-effect-4"]:active { background : purple; }
Or it's being used as a query selector, in JS, for a game's controls...
Who knows?
Custom data attributes are intended to store custom data private to the page or application, for which there are no more appropriate attributes or elements.
These attributes are not intended for use by software that is independent of the site that uses the attributes.
Every HTML element may have any number of custom data attributes specified, with any value.
For Mary Lou's tutorial - this is to control the animation that brings in the menu.
This can be re-assigned to other trigger elements - however the code that makes it live is the DIV element that comes just before - st-trigger-effects.
If you look through the code and the CSS that controls it, you will be able to re-assign that to where-ever you need to use it.
I am currently using this in a bootstrap boilerplate for a University project.
src: http://tympanus.net/codrops/2013/08/28/transitions-for-off-canvas-navigations/
I've faced two strange attributes of an html tag . They are "data-url" and "data-key".
What are they and how can they be used?
For some reasons i can't show the exact example of the HTML file I've found them in, but here are some examples from the web with such tags:
data-key
data-key
data-url
PS: I've tried to Google, but no useful results were found.
When Should I Use the Data Attribute?
Custom data attributes are intended to store custom data private to the page or application, for which there are no more appropriate attributes or elements.
This time the data attribute is used to indicate the bubble value of the notification bubble.
Profile
This time is used to show the text for the tooltip.
This is the link
When Shouldn’t I Use the Data Attribute?
We shouldn’t use data attributes for anything which already has an already established or more appropriate attribute. For example it would be inappropriate to use:
<span data-time="20:00">8pm<span>
when we could use the already defined datetime attribute within a time element like below:
<time datetime="20:00">8pm</time>
Using Data Attributes With CSS (Attribute selectors)
[data-role="page"] {
/* Styles */
}
Using Data Attributes With jQuery (.attr())
Google
$('.button').click(function(e) {
e.preventDefault();
thisdata = $(this).attr('data-info');
console.log(thisdata);
});
Examples and info from here
Those are called HTML5 Custom Data attributes.
Custom data attributes are intended to store custom data private to
the page or application, for which there are no more appropriate
attributes or elements. These attributes are not intended for use by
software that is independent of the site that uses the attributes.
Every HTML element may have any number of custom data attributes
specified, with any value.
The reason why you can't find it in Google is because those attribute are custom attributes generated by user for their own usage.
From seeing your code it seems:
The person who has written this code, wants to store some additional
information with the elements. Not sure he may handle this in
Javascript too.
What you should do is to check the Javascript code completely,
whether he is handling those data attributes or if possible check
with him.
Since you code is using jQuery library, check for .data()
method. After a complete code review, if you find it has no use,
then feel free to remove.
data-* attributes are for adding arbitrary data to an element for use solely by the code (usually client side JavaScript) running on the site hosting the HTML.
In order to tell what the three examples you give are for, we would have to reverse engineer the code that comes with them (unless they are documented on the sites) since they don't have standard meanings.
A new feature being introduced in HTML 5 is the addition of custom data attributes. Simply, the specification for custom data attributes states that any attribute that starts with “data-” will be treated as a storage area for private data (private in the sense that the end user can’t see it – it doesn’t affect layout or presentation). This allows you to write valid HTML markup (passing an HTML 5 validator) while, simultaneously, embedding data within your page. A quick example:
<li class="user" data-name="John Resig" data-city="Boston"
data-lang="js" data-food="Bacon">
<b>John says:</b> <span>Hello, how are you?</span>
</li>
I need to verify using Selenium (or similar framework) that certain HTML content/items are on the page using known unique identifiers.
I have control over the generation of the HTML, so I will mark the HTML tags with an attribute, but sometimes the usual candidates of id, name etc aren't available for me to use.
Is there an industry standard for such an attribute?
If not, anyone have any good suggestions?
The attribute shouldn't collide with any known attributes of any HTML elements or affect the web experience/behaviour (I don't care if someone reads the HTML source and sees it).
Some ideas I have are:
trace
debug
uid
Here's how I would like to use it for the example identifier "123456789":
<a trace="123456789" href="http://www.someurl.com">Click me!</a>
<span debug="123456789">Hello world</span>
<strong uid="123456789">Wow</strong>
Use a HTML5 data-* attribute.
Custom data attributes are intended to store custom data private to
the page or application, for which there are no more appropriate
attributes or elements.
More information here: http://developers.whatwg.org/elements.html#embedding-custom-non-visible-data-with-the-data-*-attributes
They won't cause any problems in older browsers: http://caniuse.com/dataset