I know that Django has default config of SSR (server-side rendering) but all the articles I have gone through mention that the Django-forms are rendered on server side and then sent to the browser. No specific information on the use case when javascript is mixed in the template.
I want to know if I use jquery tables in my Django template. Does that still render on server side? If yes then how does it render Javascript/jquery on the server-side?
I'd be glad if someone corrects me if my question itself has invalid argument.
JavaScript is for browsers so it doesn't matter if you write it in your template or add a link to it. The only way to render JS on the server-side is to actually have an engine doing that for you which Django doesn't.
What Django's template engine does is it will render the template based on the tags and HTML you provided and sends a valid HTML to the user containing the js code or js files alongside CSS and then browser runs those js and CSS codes and renders the final webpage.
This is a pretty newbie question. However, in EmberJS, I've found that both of the methods work for linking to the blog page in my application.
<p>{{#link-to 'posts'}} See my blog{{/link-to}}</p>
See my blog
Is it better to use {{link-to}} in EmberJS? How come?
The difference is that the {{link-to}} component will navigate to the specified route within the current running Ember application, while <a href="posts"> will do a new browser request to that location and re-start your Ember app at that route. You should use {{link-to}} since you'll be using the Ember internals to navigate within your single-page application and it will be a smoother user experience.
While they both can work, watch your browser closely and you'll see the anchor tag will give you a page refresh and re-launch your Ember app (though in the right location). Using a {{link-to}} will feel faster since Ember is presenting the new page via javascript rather than restarting after a page refresh. It's the difference between navigating within a single-page application, and jumping into a SPA from an external page.
While Ember does render an anchor tag in place of the {{link-to}} at run-time, it interjects to stop the default anchor tag behaviour. The docs explain it like so:
By default the {{link-to}} component prevents the default browser
action by calling preventDefault() as this sort of action bubbling is
normally handled internally and we do not want to take the browser to
a new URL (for example).
(from https://emberjs.com/api/classes/Ember.Templates.helpers.html#toc_allowing-default-action)
Also, with the {{link-to}} component you can pass a model directly into the route. This is a bit more advanced, but the Ember guides have some good examples.
https://guides.emberjs.com/v2.13.0/templates/links/
I have two controllers and two view: homepage and joblist.
I have a career.html.erb file and index.html.erb in homepage view. In career.html.erb, I have created a simple HTML form with labels and textboxes.
Homepage controller is a simple one with only view files. joblist controller is scaffolded. I have created jobs as well.
Now I just want my carrer.html.erb file form in homepage view to access and show in label the 'jobtitle' filed value of joblist controller.
Ho can I do that?
It is bit tricky. Whenever user made a request to webpage from browser, rails server map that request to controller actions by using mapping defined in routes.rb file. Routing tells rails application this request is for what controller. Now rails engine instantiate that particular controller and call action method on that controller object. SO NO METHOD OR VARIABLE IS NOT AVAILABLE IN VIEW. You can only get variables from that particular action.
For more details ruby rails web request response lifecycle
Views are rendered by controllers. You set instance variables (variables started by # sign) in controller and use these variables in view. So you need to set variables in same controllers from where you render views.
I wrote a jQuery function in my EmberJS application but it is not loading.
The jQuery function changes a graph dynamically based on input values.
My code can be viewed using this Developer tool: Application URL
I am very new to the world of web development and MVC architectures. I am currently working on django which i believe is an MVC framework. if i am right, for a web application MVC implies
views is the front end
models is the backend
controllers are the glue between frontend and backend
well if the above is true and views are the only frontend parts what exactly is the function of frontend frameworks like backbone, angular? how exactly do they deploy the mvc concept? Also when building a simple blogging site which framework would be preferrable? and also are there instances of websites working on both frontend and backend mvc frameworks? please give examples. for clarification i went through this question: In the Model-View-Controller principle, what is the Frontend and what is the Backend? but couldnt understand fully. thank you
There is no one-on-one analogy of front- and backend and the MVC model. For example, the admin of a (Django) site is generally considered to be part of the backend - it is not the part of the site the user will see - but part of the admin is definitely the View part of the MVC model. Anything a normal web user sees and/or directly interacts with is part of the frontend, everything else is part of the backend.
Now what is the MVC framework used in Django? We have:
The Model: this is the part of the application that holds the state of the application. In Django, a big part of this is the database and it's abstraction layer, the Django models. Other parts are user sessions and the request variable.
The View: this is the part of the application that presents the state of the application to the user. Django views and templates are responsible for this. Any data you see when you open up the website is the View part of MVC. The overall presentation is also part of this.
The Controller: this is the part of the application that represents any action you, the user, takes. Django is not truly a separated MVC framework because the View part and the Controller part are so tightly interwoven: any link, form or button you see on the site is a controller. It tells the site to do an action, such as present a different view (e.g. a link), or change the state of the model (e.g. an edit form).
What about Backbone or Angular? Why do you need two different MVC frameworks in a single application?
Django is a server-side framework. Every action happens on the server. If you click a link or submit a form, you send a request to the server and the server sends back a complete, static response (static in the sense that the page doesn't change once it's in your browser). You can't use Django to use logic client-side, as it is a python framework that runs on your server, not in your client's browser. Instead, it's Javascript's job to add any client-side logic, e.g. to reorder a list of items on the page or to dynamically add a new one. Now each page can be seen as some kind of mini-application.
Backbone and Angular are examples of MVC frameworks for such client-side applications. It supplies the client-side application logic that a server-side framework such as Django lacks, and surprisingly the people who like an MVC framework to develop a server-side application generally also like to use an MVC framework to develop a client-side application.
Django is a kind-of hybrid version of the Model-View-Controller model. The Django documentation generally describes it as a Model-View-Template model instead. Generally, the template (Django HTML with template tags, etc.) is generally matched to the normal View, providing the user's view in the way of web pages. The view in Django generally takes the place of the Controller, as it works between the Model, taking data from databases and defining new objects, and the View, which in this case is the Template. The Model is the same as normal in Django, providing the definition for different objects. So while the Model-View-Controller is normally the model for most languages, it is more so a Model-View-Template model, with the View being different than it is normally. Read more below:
http://jeffcroft.com/blog/2007/jan/11/django-and-mtv/
I am looking at Django, and patterns for web development.
What I am favoring at the moment(2014-01) is.
Use Django (restful/json) as the MC, Model/controller, or backed data and logic.
The controller part in Django refers to business rules and access control.
then use a javascript framework and bit of html as the client side code. View/controller.
In practice, the client/browser loads a javascript program, View/controller that then does restful queries to the backed model/controller