I am adding some functionality to an existing Microsoft MVC 3 application. I cannot change the existing structure of the app itself while I do need to add some new functionality to the page. I have angular running in a div (hidden on load via jquery dialog). The MVC app has several tabs on the page. Each time a tab is chosen, the a partial cshtml (razor) loads. Along with that partial, my angular template is included. The partial references a js file that contains the angular controller. When it is first loaded and the user opens the tab and open the jquery dialog containing angular, everything works fine. I started to notice some funny behavior after the changes are saved. I noticed the same irregular behavior if I closed the dialog containing the angular template, switched to another tab, then switched back to the tab containing the angular template. Here's what is happening:
The partial being loaded by MVC reloads the angular template which initiates the angularjs controller method in the referenced js file
A new $scope is being generated each time this occurs.
Each time a controller method is invoked (via ng-click event tied to a button on the template) teh method will execute n number of times with n being the number of times the partial has been loaded since the last full page refresh.
I proved this method by logging the $scope object to the window in the start of the controller method
window['scope_' + new Date().getTime().toString()] = $scope;
After each partial page load, a new $scope object is logged to the window. Pressing a button on the template invoked a certain method tied to the ng-click event. This event fires multiple times. But calling the method manually in the console using the oldest recorded scope object in the window
scope_1378413848781.$apply(scope_1378413848781.getSomeData())
it works as intended. So, my question is, how do I prevent the controller from adding a new scope every time the MVC framework reloads the partial?
Here are some of the things I've tried that didn't work:
Adding a global flag and exiting the controller method if it was set
moving the controller reference to the _layout.cshtml file
destroying the scope when the dialog containing the template is closed
One final note, I am not using the angular route provider which I know can cause the controller to execute twice when used in conjunction with .
It appears that Angularjs was not meant to be used in this fashion. Per the angular docs:
You can use Angular to develop both single-page and round-trip apps, but Angular is designed primarily for developing single-page apps...You normally wouldn't want to load Angular with every page change, as would be the case with using Angular in a round-trip app.
To resolve the issue, I moved the angular template as well as the reference to the controller and angular.min.js to the shared _Layout.cshtml file. This partial file loads first and is only reloaded when the entire page is refreshed. Adding angular references and loading controllers in js files referenced in asp.net mvc 3 partials will cause scope replication that can be difficult to detect.
Related
already I begun Switch ASP.net Web to SPA for use in PWA and all Partial Views call with AJAX only. but now I have a problem, I wanna set a back button like IOS for back to previous Partial View. I want to know if I have the ability to identify the history of my previous AJAX calls and link to them ?
I know that the webpage that is opened by the user is part of the view. This one is easy, but what about js code calling the server to retrieve data via ajax? Is this part of the controller or still the view?
Can the view request data like this?
Thank you very much for any help.
Javascript, including Ajax, is a client-side technology. Therefore, in the context of MVC, any js script must be part of a template file.
Note that a template file is not the view (the V in MVC), but a part of it. The view should incorporate both server-side components (classes, interfaces, etc) and client-side components (html, js, css, images, etc). For example, an instance of a view class could read some data from the domain model and then load and render a certain template file, injecting the fetched data into it (formatted), in order to be printed on the screen.
So, an ajax object should be defined in a template file. Its request to the server is handled either by the controller, or by the server-side components of the view, depending on the MVC approach that you are choosing to implement. Though, the server response should always be created by the server-side components of the view.
I've got a component that downloads data from an API. When the user clicks Search, the content from the API is fetched via AJAX. This content from the API is in JSON and has got an ID of the product inside. I am able to create new HTML elements based on this content and put them inside my site, but I would like every created on the fly element to have routerLink="/detailsPage/itemID" working, so that after clicking it would route to detailsPage with apropriate ID. How to do it in the most simple way? I assume some recompiling of refreshing is needed.
The answer to this question is HTTPClient - Angular offers it as an easier way to use XMLHttpRequest (AJAX) in Angular applications, and using it also makes sure that routerLink or any other Angular directives will work on objects created dynamically with this method.
Angular - HTTPClient
I'm developping a jqm application with spring mobile in the back-end.
Whenever I hit the browser refresh button on my mobile phone the page is completely devastated afterwards. Browsers back-button works properly.
The data are still available due prg pattern (flashAttributes in Spring) after refresh. Only the view is malformed.
Any ideas how to solve this problem?
From jQuery Mobile docs :
The simplest approach when building a jQuery Mobile site is to reference the same set of stylesheets and scripts in the head of every page. If you need to load in specific scripts or styles for a particular page, we recommend binding logic to the pageinit event (details below) to run necessary code when a specific page is created (which can be determined by its id attribute, or a number of other ways). Following this approach will ensure that the code executes if the page is loaded directly or is pulled in and shown via Ajax
So what happens is - in jQuery Mobile, the scripts and styles defined in the head are loaded only once. So, in normal conditions, it works fine, as all the pages will use the scripts loaded from the first page.
But. When you refresh a page in-between, it triggers a page-reload instead of the ajax navigation model thatjqm uses. So all the scripts and styles loaded from the first page will not be included from here on out.
What you need to do is "reference the same set of stylesheets and scripts in the head of every page", so that even if you hit refresh in the middle, the scripts and styles that had been loaded from the head of the first page are loaded again.
I recommend you read the docs from the above link fully to gain a better understanding.
I am working on a mobile website in ASP.NET MVC3. I have a page where i have search bar in my header. this header is coming from my Layout page which is common to all other Views. And inside my specific page, I have page specific content(forms).
For my Customer/Add action, I return the Add View of Customer which is strongly typed to my CustomerViewModel. I will have form tag in my Add View which will be posted to HttpPost Add Action method when form gets submitted. That is fine. My question is how will i handle the search box content ? I believe only one form is allowed in the page.So if i have a SearchViewModel which is binded to my Search View(Partial), It is going to be 2 forms in my page. So i can not do that.
I can handle the search part by reading the content in java script and calling another action to get Search results.Is that the only way to do that ? I am worried about those devices where java script is disabled. What should i do ? Please advice
No. You can have more than 1 form on the page. In fact, here you should. Your Add Customer page should submit to 1 action method, but your search form should submit to a different action method.
If you are familiar with webforms, that framework only allows you to have 1 form on the page, but not because HTML requires it. Webforms requires it because it is the only way the framework can carry all of the data from various server controls across POST requests (using ViewState). Webforms has historically not been very HTML or HTTP friendly.
You just can't have forms nested within other forms in HTML, but it is completely legal (and recommended in MVC) to have more than 1 form on a page.
As for AJAX, I would not worry about devices that do not have javascript enabled. There are only like 6 or 7 people on the planet that don't have javascript on their web devices, and if someone disables javascript, they won't be able to experience 99% of the rest of the web anyhow.