I pass a variable from the views.py file to multiple javascript template and want to refresh that variable every time I click on certain parts of the window. Loading the variable from views to the template is simple enough, but I don't know how to pass that variable back to the views then send it back to update the templates.
You would have to do that via Ajax. It's the only way you would be able to execute a server-side view and hand back data, most likely JSON, that could be used to update a JavaScript variable.
If you're looking for a way to automatically update the DOM when changes in client-side data occur, I highly recommend Knockout.js.
Related
suppose I want to have a data provider element for my user, like
<user-data-provider user-data="{{data}}"></user-data-provider>
which sends an ajax request and gets the logged in user.
Suppose I want to access my user data in different pages, and I add this tag to wherever I need, but the problem is, every time the browser sees this tag, makes an ajax again and I have to wait until data is fetched!
I know I can make a variable in my main page and pass it along child pages, but that seems like overkill to me !
how can I persist user data across different pages and part of my app?
thank you in advance
There are different ways to do this.
You can use use a monostate pattern
You can have one instance of your user-data-provider element in your root element or index.html and use iron-signals to transmit the data to all other elements that want to consume it
You can use iron-meta to have global state
Use an external state management framework (i.e. redux). There is a polymer wrapper for it: polymer-redux
I would recommend using an external state mangement framework such as redux.
Some of the solutions are shown here:
Polymer 1.0 Global Variables
I used pouchdb for my data store, and used polymer's predefined elements to work with it
now every time that I need data, I just use that component
I am working in AngularJS application with Spring rest as backend. I am pretty new to angularjs.
I have a UI page where i display some list of objects in table.There is an edit button against every record.When i click edit, another page opens which set the data accordingly.
The issue is, being on edit page, if I refresh the browser, I loss my data. One way I can think is to make another rest call but I want to avoid making any rest call.
Is there any way to retain data on the page on refresh or making rest call is better solution?
I would think the cleanest way to do it is to make a REST call, as the data could have changed on the server. However, if you want to avoid the call anyway, you may use localstorage. Just store the data in your table in localstore with key value pairs (assign some unique key to every row). You could use this plugin: Angular LocalStorage
I recently wrote a PHP wrapper class for a new API we are using and have been asked to setup a demo which makes use of it. Certain features can be called directly from PHP, however things such as performing actions on button clicks requires I make use of JS/AJAX.
As I already have an instance of the object in my main PHP file, can I pass this as a parameter to JS and then pass it through Ajax to my handler or is it necessary to establish two separate instances?
The closest thing to doing what you want that I can think of would be copying the PHP object to a JavaScript variable via json_encode and then passing that variable back to your PHP code during the AJAX event via the data parameter. PHP code doesn't persist in the way that you seem to be describing - once a page has been requested by a browser, your PHP code for that page is done, there are no variables persisted by the server after that point.
I want to know if it is possible to directly modify and save a model instance in the HTML Template and not via a view and extra URL.
My user has a Boolean Property, I want to display it as a toggle button on the website and the user should be able to toggle it on or off without leaving the website or reloading it.
class User(AbstractBaseUser, PermissionsMixin):
...
autoplay_enabled = models.BooleanField(default=True)
...
Is this possible without an extra view or form?
Basically I just need to set
request.user.autoplay_enabled = False (or True)
and then save() it
If I can't modify the object directly in the HTML template is it at least possible to just execute a function I have defined somewhere in my Python code, without having the need to create a new view?
What you're asking doesn't make any sense at all. HTML is just sent to the browser for display. You can't do anything "from HTML" without making some kind of request to the server, and the server won't do anything unless that request is received by some code - eg a view connected to a URL.
If you want something to happen without refreshing the page, you need to use Ajax. You can use a simple Ajax POST to a view that toggles the value and saves it - it only needs a dozen lines of code between front and back end.
I'm looking to capture and save the state of a page (Django template + backend) after the user makes some modifications (through JQuery) to the appearance of the page. Now that I've gotten hold of the innerHTML using a JS variable, I need to send it over to the Django view that will do the saving. How do I call this Django view and pass it the JS variable?
P.S: First ever question on stackoverflow, please let me know if the question isn't clear or is improperly formatted.
Handiest way to get started is to first make a proper form and a django view that reacts to it ("request.post"). The form should have fields for whatever you're changing in the page.
Next up, submit that form's variables from your page with jquery.ajax.
So the idea is to isolate the various problems:
What should be the form parameters?
Get a view running that makes the actual changes.
Get the javascript working.