Where does Angular JS fit in the browser rendering process? - html

From my understanding the browser rendering process is essentially happening in the following steps:
HTML is parsed into DOM tree
DOM tree is converted to a render tree
Layout
Paint
Where does Angular JS come in the picture here? For example if I have an expression like
<div>{{test}}</div>
or
<div ng-include="..."></div>
Is it right to think that Angular does the interpolation or HTML injection, and then the browser takes the resulting HTML code, and goes through steps 1-4?

Angular JS documentation says:
When Angular starts your application, it parses and processes this
new markup from the template using the compiler. The loaded,
transformed and rendered DOM is basically the view
Here a template means:
HTML code that contains Angular specific attributes.
For more information on how AngularJs works and what it can do, please read the documentation provided:
https://docs.angularjs.org/guide/concepts
There is an in-depth tutorial which provide more information on it.
I hope this could help you get started with it :)

Related

Extend Markdown Parser to render custom code blocks

I am building a static blog, which uses Marked to parse markdown. I want to be able to have code blocks with tabs.
I want to parse code that looks like this:
```JavaScript
var geolocation = require("nativescript-geolocation");
```
```TypeScript
import geolocation = require("nativescript-geolocation");
```
To something like this (from the angular2 docs), where the tab names would be JavaScript and TypeScript.
I am programming in JavaScript (nodeJs), so I could manually render this if required? What would a custom implementation of a code block tab look like?
I am not sure if there is a special name for these, as I can't really seem to find any examples or templates.
I think answer is: 'Marked' does not support custom tags. I've spend few hours trying to find some way to extend it and finally switched to showdown.
It appears to be really easy to implement one ( her is expandable section tag example ).
Extension 'showdownjs/prettify-extension' implements code highlighting using Google Prettify.

Using node and node-phantom to scrape AngularJS Application

I have a node script set up to scrape pages from an AngularJS application and then generate code needed for testing purposes. It works great except for one thing. ng-if. Since ng-if removes elements from the dom the script never sees these blocks of code. I can't remove the ng-if's. So I'm wondering if there is some way to intercept the html between when node-phantom requests the page and when it actually loads everything in to phantoms dom. What I'm hoping to do is simply set all the ng-if's to true so that all content is available. Does anyone have any ideas for this?
EDIT I'm using phantomjs-node not node-phantom.
My Final solution was to scrape the page for all of the comment tags. Then filter through to find the ones that contained ng-ifs and parse out variable names from those tags. Then I tapped into Angular's $scope and set all of the variables to true. Forcing everything that is hidden on the page to be visible.

How to use Thymeleaf th:text in reactJS

I am running a springboot application with Thymeleaf and reactJS. All the HTML text are read from message.properties by using th:text in the pages, but when I have th:text in reactJS HTML block, reactJS seems angry about it.
render() {
return (
<input type="text" th:text="#{home.welcome}">
)
}
The error is:
Namespace tags are not supported. ReactJSX is not XML.
Is there a walkaround besides using dangerouslySetInnerHTML?
Thank you!
There is no sane workaround.
You are getting this error because Thymeleaf outputs XML, and JSX parsers do not parse XML.
You did this because JSX looks very, very similar to XML. But they are very, very different, and even if you somehow hacked Thymeleaf to strip namespaced attributes and managed to get a component to render, it would be merely a fleeting moment of duct-taped-together, jury-rigged code that will fall apart under further use.
This is a really, really bad idea because JSX is Javascript. You are generating Javascript on the fly. Just to name a few reasons this will not work in the long term:
This makes your components difficult if not impossible to test.
Reasoning about application state will be a nightmare as you will struggle to figure out if the source of a certain state is coming from Thymeleaf or JS.
Your application will completely grind to a halt if Thymeleaf outputs bad JS.
These problems will all get worse with time (Thyme?) as as developers abuse the ease with which they can render server-side data to the client-side, leading to an insane application architecture.
Do not do this. Just use Thymeleaf, or just use React.
Sample Alternative: I primarily work on a React application backed by a Java backend. So I understand how someone could stumble upon this hybrid and think it might be a good idea. You are likely already using Thymeleaf and are trying to figure out how you can avoid rewriting your servlets but still get the power of React.
We were in a similar boat two years ago, except with an aging JSP frontend, but the difference is negligible. What we did (and it works well) is use a JSP page to bootstrap the entire React application. There is now one JSP page that we render to the user. This JSP page outputs JSON into a single <script> tag that contains some initial startup data that we would otherwise have to fetch immediately. This contains resources, properties, and just plain data.
We then output another <script> that points to the location of a compiled JS module containing the entire standalone React application. This application loads the JSON data once when it starts up and then makes backend calls for the rest. In some places, we have to use JSP for these, which is less than ideal but still better than your solution. What we do is have the JSP pages output a single attribute containing JSON. In this way (and with some careful pruning by our XHR library) we get a poor man's data interchange layer built atop a JSP framework we don't have time to change.
It is definitely not ideal, but it works well and we have benefited vastly from the many advantages of React. When we do have issues with this peculiar implementation, they are easy to isolate and resolve.
It is possible wrap ReactJS apps in Thymeleaf. Think if you want a static persistent part (like some links, or even just displayed data), you could use Thymeleaf. If you have a complicated part (something that requires DOM repaints, shared data, updates from UI/Sockets/whatever), you could use React.
If you need to pass state you could use Redux/other methods.
You could have your backend send data via a rest API to the React part and just render your simple parts as fragments or as whole chunks of plain HTML using Thymeleaf.
Remember, Thymeleaf is really just HTML. React is virtual DOM that renders as HTML. It's actually fairly easy to migrate one to the other. So you could write anything "Static" or that does not respond much to UI, in Thymeleaf/HTML. You could also just render those parts in React too, but without State.
Thymeleaf 3 allows you to render variables from your Java to a separate JS file. So that is also an option to pass into JSX
function showCode() {
var code = /*[[${code}]]*/ '12345';
document.getElementById('code').innerHTML = code;
}
Now you can use data- prefix attributes (ex. data-th-text="${message}").
https://www.thymeleaf.org/doc/tutorials/3.0/usingthymeleaf.html#support-for-html5-friendly-attribute-and-element-names

Semantic Media Wiki: Displaying a SVG element of a HTML page

I have a HTML page that displays a SVG element (a Business process diagram) using some javascript libraries. A String variable, say 'str' needs to be given to html function.
After reading this, I plan to use widgets. So far I understand that I need to copy all scripts to Widgets: Test. For creating the hook, I write
{{#widget:Test|str=UserTask_1}}
The problem is that UserTask_1 is a variable as well. It is different each time.
Can someone help how can I add this dynamic information to my hook? This hook is a hyperlink from a previous page. In the previous page, I send the str=UserTask_1 through JavaWiki Bot.
PS: I have come-across SMW for first time. Please excuse if my language is not very technical at the moment.
Thanks.

How are DOM/rendered html and Coded-Ui are related, can coded-ui test a web application without even considering how that page is rendered in DOM?

I want to know how the coded-ui in web application utilizes DOM of that page. Or is it related to that page's rendered html is coming?
Edited: If suppose i have a grid having rows and column and i want to capture any particular column in it, then do coded-ui takes the help of the rendered html in this process (id,tagname etc) ?
you can utilize the htmlcontrols which is listed in below url:
https://msdn.microsoft.com/en-us/library/microsoft.visualstudio.testtools.uitesting.htmlcontrols.aspx
I used codedui jquery extensions available in NuGet here
. Once you will add this dll as a reference you can make use ExecuteScript() method for running a jquery script inside coded-ui. Similary you can make use of other built in members.