Fire an event when user moves out of speciifc route in AngularJS - angularjs

Question

I am using AngularJS 1.3. Assume I have created several routes in my application. But when user hits a specifc route/url & then tries to move to another route/url, I want to fire some event. I do not want to fire this event on every URL change.
So only when user comes out of this url http://localhost:9000/data/55677c/edit, I want to fire one function available in XYZ controller.
Here is my scenario:
I have a page which looks like this:
<div class="well">
<button id='edit-btn' type="button" ng-click='saveContent()'>
<div ng-include="'components/grid/comOne.html'"></div>
</div>
components/grid/comOne.html page contains one grid and it has its own controller which takes care of data management of the grid.
This grid is shown in two pages. One in editable mode and one is non-ediatble mode. While user is in editable mode and try to move out of the page without saving the info, I need to fire an event in order to discard ant changes user has made to the grid data.
Please suggest

Answer 1

If the listening controller is a parent controller you could $emit the event.
Or you could have a common service like this:
angular.module('x').factory('CommonLogic', function(){
var pageChangeListeners = [];
return {
listenToPageChange: listenToPageChange
};
function listenToPageChange(callback){
pageChangeListeners.push(callback);
}
function pageChanged(){
for(var i = 0; i < pageChangeListeners.length; i++){
pageChangeListeners[i]();
}
}
});
then when leaving that url (track that via $routeChangeStart) you can call: commonLogic.pageChanged()
In the controller where you want to take action just:
commonLogic.listenToPageChange(function(){..}).
Obviously this should be improved to avoid duplicate registration of the listener ... etc.
I hope I'm not overcomplicating this. Could you describe your use case in more detail ?

Answer 2

I guess you want to use $routeChangeStart:
$rootScope.$on( "$routeChangeStart", function(event, next, current) {
});
You can put this in the scope of your current controller which might be edit as your url says.
From the docs:
$routeChangeStart
Broadcasted before a route change. At this point the route services starts resolving all of the dependencies needed for the route change to occur. Typically this involves fetching the view template as well as any dependencies defined in resolve route property. Once all of the dependencies are resolved $routeChangeSuccess is fired.
The route change (and the $location change that triggered it) can be prevented by calling preventDefault method of the event. See $rootScope.Scope for more details about event object.
Type:broadcast
Target:root scope