Better approach in cloning elements for Datatables custom renderer - datatables

I have a custom renderer for a column in DataTables. As you would know, DataTables expects the custom renderer to return a literal representation of what you would like to display on that column. Something like:
return '<div class="fancy">' + somevalue + '</div>';
I am already using this approach but I wonder how I could do it better. Like for example saving the template somewhere and returning it cloned. Consider this custom column rendering returns a big nested element. Is it still wise and ok to return it just like how it is now? Or is it better to use other approaches like HTML5 templating (with querySelector()) or jQuery .clone() method? Though either of these methods can't return a literal representation but only a node or a DocumentFragment which must be appended to the DOM before use. But are they still viable options here?
Things to consider here is maybe reducing the DOM footprint? Client-side and/or server-side performance? Better coding approaches?

Related

How to prevent hydration of Nuxt when using SSR?

We are using this approach to rendering content:
<div id="full-article" v-html="content"></div>
this.content = api.response.data
In this approach, "content" is retrieved from an API, but because we also use Server-Side-Rendering (SSR), the final HTML is turned into this:
<div id="full-article">$real_html_content</div>
this.content = $real_html_content
This approach means that the content is repeated, once as rendered HTML, and once as a javascript variable. But in this scenario we are not using the javascript content variable. The fact that it's still included in the final HTML page means that the page size is twice as big as necessary. How can we prevent this? Is there some way of hiding/removing javascript content that has already been rendered by SSR?
Alternatively, maybe it would be better to deal with this content differently, perhaps insert it at a later stage and not involve Nuxt or SSR?
This is what you're looking for: https://github.com/maoberlehner/vue-lazy-hydration
Created by Markus Oberlehner who was seeking to avoid shipping to much JS to the frontend, especially when this was not needed.
You do have several options but this is how it can be used
<lazy-hydrate never>
<article-content :content="article.content"/>
</lazy-hydrate>
In this case, the hydration (injecting JS into static content) will never happen. There are other interesting options that can be used too!
Keep in mind that this was more of a proof of concept, hence why Markus still considers it as beta-ish. This project will probably die at some point because Vue3/Nuxt3 will be able to do this in an official way.
Still, even if I did not tried it yet, you can totally use it as of right now and enjoy a JS-light experience, it should work!

Is there a way to highlight required input fields in Vue Formulation?

So I am trying to create a form using Vue Formulation. I have a few input fields that are required. Is it even possible to highlight them somehow? I have read Vue Formulation doc, but could not find the answer.
You could simply give the required fields a different styling/CSS class.
If you are really fancy, you could try to read the attributes of the DOM elements (with attr() or refs), but haven't tried that and it is probably not worthwhile.

Vue JSX bind to class name

I'm building a simple TodoMVC app using Vue + JSX, but the documentation seems to be seriously lacking. Thus, I'm writing down the points I need to address as part of a CR to the appropriate projects. The only document I've read as of yet is the guide, which doesn't cover much JSX at all. I don't know much about how the framework works yet, but I sure prefer using the render method over the string templates for performance/network reasons.
question
What's the proper way to create a class name binding in Vue + JSX? In my TodoItem component, creating either a class or className attribute makes Babel throw a compile error complaining the API is deprecated (and suggesting I add several seemingly unrelated dependencies to the mix). Plus, including the class property in the data object seems to change nothing.
secondary question
The lack of documentation, plus the wording on the guide gives the impression JSX is not the "proper" way to write Vue components. Is that so? What's the idiomatic way to do it, given I don't want to ship the compiler along with my app?
links
code on codepan
I sure prefer using the render method over the string templates for performance/network reasons.
If you're writing *.vue files and bundling them with vue-loader (Webpack), the HTML template gets compiled into a JavaScript render function anyway, so there isn't really any kind of performance issues in that sense.
On the other hand, if you're writing your Vue components with string templates like this:
new Vue({
template: '<div>Hello</div>'
})
then you'll need the Vue template compiler at runtime to convert the string into a render function.
Typically people would opt for writing render functions manually if they need to do something specific that would be difficult/impossible to do with the HTML template alone.
You've probably already read the docs, but just in case, the relevant sections are:
Render Functions & JSX
The Data Object In-Depth
babel-plugin-transform-vue-jsx Usage
What's the proper way to create a class name binding in Vue + JSX?
You would just bind to the class attribute like you would any other attribute:
<div class={this.klass}>
data() {
return {
klass: 'foo'
}
}
The lack of documentation, plus the wording on the guide gives the impression JSX is not the "proper" way to write Vue components. Is that so? What's the idiomatic way to do it, given I don't want to ship the compiler along with my app?
JSX is definitely supported, but it is not the recommended approach. The recommended approach is to write *.vue files and load them with vue-loader (if using Webpack).
Vue comes in two versions, one with and one without the template compiler. The one with the compiler included is only for development and should not be used for production builds (unless you require string template to render function compilation at runtime, which is unlikely). See Explanation of Build Files for more info.
Typically you write HTML string templates, and they get compiled to render functions (by vue-loader) at build time.

Rendering an aurelia custom element in ag-grid header

Is there an "easy" way to render a custom element in ag-grid header cell? The headercomponent interface seems like an overly cumbersome approach to a seemingly simple problem and I have not been successful with this approach. The closest I have come is to use something like:
header-cell-render.bind="myHeaderRenderer"
which is currently a function returning a string of HTML. While this "works" (though I understand it is deprecated), in the sense that the html is injected into the DOM, only primitive HTML renders. Meaning I can return something like:
<input type="checkbox" />
and it will render a checkbox, but I cannot return something like:
<my-custom-element></my-custom-element>
I can see that markup in the DOM, but the element doesn't "process", that is the Aurelia aspect of the control is not executed.
I am using the latest versions of ag-grid, ag-grid-aurelia.
Any help would be greatly appreciated.
This is currently not possible out of the box with ag-grid-aurelia.
This is because ag-grid-aurelia makes no special handling for this binding. The proper way to handle this is using replaceable parts which allows you to specify a template for Aurelia to inject and consume. ag-grid makes this a bit harder since it seems the only native tool for injecting content into the header is by passing an HTML string or an HTML element in the column configuration. This can likely be added to the ag-grid-aurelia library by using a combination of replaceable parts and the #children decorator to gain access to the aurelia-rendered header element and pass it to the column configuration.

What is the point of getEl() in extjs4

I have a listener that is called when a tab is activated.
, listeners: {
activate: function(tab){
var first = tab.down('input'), // will be null
firstEl = tab.getEl().down('input'); // will contain first input element
I'm not having a lot of luck understanding the relationship between tab and tab.getEl(). If this was jquery, $(tab) would give me a jquery element which would largely expand on my set of options. extjs seems to be almost backwards in this regards, or at least more complicated.
I'm trying to understand when and why I need getEl() so that it is less of a development crapshoot about what will and won't work. In other places I do things like:
showFieldHelpOnBlur = function(ctrl) {
ctrl.up('form').down('#helptext').update("");
}
without the getEl(). In this case form is an element tag just like input (above), but I don't need the getEl() before I use it. In general the two sets of functionality that share the same names but don't work the same are frustrating, and the docs don't seem to give any clue as to why there are multiple methods with the same names that do different things, or do similar things in a different way.
Found some similar issues with focus(), but those might make more sense if I just understood why are there are 2 seemingly parallel sets of methods for what are essentially DOM elements wrapped in additional functionality.
I think at the core of your confusion is how you approach the development using ExtJS vs JQuery.
JQuery is all about DOM manipulation and low level API. ExtJS approach is very different, it wants you to think of your page structure as a hierarchy of ExtJS components that are responsible for rendering appropriate HTML. So ExtJS is essentially saying: "Don't worry about html, we'll take care of it - you focus on the larger components, layouts, events, etc. "
You will say "Whoa Nelly! What do you mean don't worry about html? I want control!" And ExtJS will respond OK - we have a wrapper object called Element (http://docs.sencha.com/extjs/4.1.3/#!/api/Ext.dom.Element) you can use it to do DOM manipulation just like you are used to with JQuery .. but be cautious. Because if you manage your own HTML we can't be responsible for what happens to your layouts and components that are not managed by the framework.
My advice is this - when in Rome do like Romans do :)
If you are going to be using ExtJS to build apps - embrace the way ExtJS is designed to work. Learn the different layout mechanics and numerous component types available to you out of the box. Use the MVC development pattern to beautifully organize your code. Use the examples to your advantage. Study the architecture and component guides - these are very useful. Understanding ComponentQuery class is a must (all those up/down methods and query).
At the end, when you have gained comfort using ExtJS components and their style of development you will be very efficient at building your UI compositions and can build much more complex applications than before.
Good Luck!
Pro Tip: Do yourself a favor and get Illuminations for Developers plugin for Firebug - it will open your eyes to see things using component structure rather than HTML elements.