In Ember, the query parameter values are sticky by default; in a way that any changes made to the query parameter, the new value of query parameter will be preserved by reentering the route.
Syntax
Ember.Controller.extend ({ queryParams: ['paramValue'], paramValue:true/false });
Example
The example given below specifies the use of sticky query parameter values. Create a new route and name it as stickyqueryparam and open the router.js file to define the URL mappings −
import Ember from 'ember'; //Access to Ember.js library as variable Ember import config from './config/environment'; //It provides access to app's configuration data as variable config //The const declares read only variable const Router = Ember.Router.extend ({ location: config.locationType, rootURL: config.rootURL }); //Defines URL mappings that takes parameter as an object to create the routes Router.map(function() { this.route('stickyqueryparam'); }); //It specifies Router variable available to other parts of the app export default Router;
Open the file application.hbs created under app/templates/ with the following code −
<h2>Sticky Query Param Values</h2> {{#link-to 'stickyqueryparam'}}Click here to open the page{{/link-to}}
When you click the above link, it opens the sticky query parameter template page. The stickyqueryparam.hbs file contains the following code −
<h2>My Page</h2> {{link-to 'Show' (query-params showThing=true)}} {{link-to 'Hide' (query-params showThing=false)}} <br> {{#if showThing}} <b>Welcome to Adglob..</b> {{/if}} {{outlet}}
Now open the stickyqueryparam.js file created under app/controllers/ with the below code −
import Ember from 'ember'; export default Ember.Controller.extend ({ queryParams: ['showThing'], //showThing would be false, if only the route's model is changing showThing: false });
Output
Run the ember server and you will receive the following output −
When you click on the link, it will open the sticky query param template page by providing Show and Hide links −
When you click on the Show link, it will display the text and Hide link hides the text −
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