I'm using angular-timer and I'm just a little confused how to track its events. For example, I want to do something after time is up, but I can't see any events on console log.
vm.add20Seconds = function() {
$scope.$broadcast('timer-add-cd-seconds', 20);
}
$scope.$on('timer-add-cd-seconds', function (event, data) {
console.log(data); // 'Some data'
});
The console is empty.
https://github.com/siddii/angular-timer/blob/master/examples/angularjs-add-countdown-seconds.html
As the code given in link is not seems to be updated, I think you changed it to use controllerAs syntax. So your button html will use vm alias while calling controller method. Assuming you used ng-controller="MyAppController as vm"
Markup
<button type="button" ng-click="vm.add20Seconds()">Add 20 Seconds</button>
Else wanted to use $scope in your controller then simply change method to $scope.add20Seconds instead of vm.add20Seconds
Update
To get call a function after 20 seconds over, you could use $timeout service here, that will call and specified callback when mentioned $timeout completed.
Code
vm.add20Seconds = function() {
$scope.$broadcast('timer-add-cd-seconds', 20);
}
var myCallbackAfterTimeout = function(){
//add your code.
}
$scope.$on('timer-add-cd-seconds', function (event, data) {
console.log(data); // 'Some data'
$timeout(myCallbackAfterTimeout, data); //data is nothing but timeout milliseconds
});
Include $timeout dependency in your controller before using it.
if you are looking for a good article about using the scope tree As A Publish And Subscribe (Pub/Sub) mechanism in angularJS please check this link
Related
I'm rather new to angular and I'm trying to integrate np-autocomplete in my application (https://github.com/ng-pros/np-autocomplete). However I can only get it to work when I'm passing a html string as a template inside the $scope.options and it doesn't work when I want to load it from a separate html.
the Code for my app looks as follows:
var eventsApp = angular.module('eventsApp',['ng-pros.directive.autocomplete'])
eventsApp.run(function($templateCache, $http) {
$http.get('test.html', {
cache: $templateCache
});
console.log($templateCache.get('test.html')) // --> returns undefined
setTimeout(function() {
console.log($templateCache.get('test.html')) // --> works fine
}, 1000);
//$templateCache.put('test.html', 'html string') //Would solve my issue in the controller,
//but I would rather prefer to load it from a separate html as I'm trying above
Inside my controller I am setting the options for autocomplete as follows:
controllers.createNewEventController = function ($scope) {
$scope.options = {
url: 'https://api.github.com/search/repositories',
delay: 300,
dataHolder: 'items',
searchParam: 'q',
itemTemplateUrl: 'test.html', // <-- Does not work
};
//other stuff...
}
however, it seems that test.html is undefined by the time np-autocomplete wants to use it (as it is also in first console.log above).
So my intuition tells me that the test.html is probably accessed in the controller before it is loaded in eventsApp.run(...). However I am not sure how to solve that?
Any help would be highly appreciated.
You are most likely correct in your assumption.
The call by $http is asynchronous, but the run block will not wait for it to finish. It will continue to execute and the execution will hit the controller etc before the template has been retrieved and cached.
One solution is to first retrieve all templates that you need then manually bootstrap your application.
Another way that should work is to defer the execution of the np-autocomplete directive until the template has been retrieved.
To prevent np-autocomplete from running too early you can use ng-if:
<div np-autocomplete="options" ng-if="viewModel.isReady"></div>
When the template has been retrieved you can fire an event:
$http.get('test.html', {
cache: $templateCache
}).success(function() {
$rootScope.$broadcast('templateIsReady');
});
In your controller listen for the event and react:
$scope.$on('templateIsReady', function () {
$scope.viewModel.isReady = true;
});
If you want you can stop listening immediately since the event should only fire once anyway:
var stopListening = $scope.$on('templateIsReady', function() {
$scope.viewModel.isReady = true;
stopListening();
});
I have been working with the excelent ngStorage plugin for angular.
When setting it up you can declare a $scope-node connected to the localstorage like this:
$scope.$store = $localStorage;
$scope.$store is now accessible in all controllers etc.
I want to remove some stuff from localstorage and access it using broadcast instead.
In my init I performed:
$scope.taskarr = [];
$rootScope.$broadcast('taskarrbroad',$scope.taskarr);
What is required in order to add, remove and $watch this array, none of the mentioned seem to work.
Here, nothing happens
controller('textController', function($scope,$routeParams){
$scope.$watch('taskarrbroad.length', function(){
console.log($scope.taskarr.map(function(task){
return task.content;
}).join('\n'));
})
})
Here I can access $scope.taskarr and update it, but the view isn't updated. $scope.$apply() didn't help either (the timeout is because it's already within a digest.
controller('stateSwitchController', function($scope, $routeParams, $timeout){
$scope.taskarr = $scope.$store[$routeParams.state].taskarr || [];
console.log($scope.taskarr);
$timeout(function() {
$scope.$apply();
})
}).
$broadcast is a way to send events to other parts of your application. When you broadcast an event, someone else has to listen to that even with $on(). Something like:
// Some controller
$rootScope.$broadcast('my-event', eventData);
// Some other controller
$scope.$on('my-event', function() {
console.log('my-event fired!')
});
$watch is something else, it's not an event listener per se, it's a way to attach a function that gets called when that value changes, and that value has to be on the scope. So your watch should look like this:
$scope.$watch('taskarr.length', function(){
});
Since you've named the array taskarr on the scope.
I am writing a small Angular web application and have run into problems when it comes to loading the data. I am using Firebase as datasource and found the AngularFire project which sounded nice. However, I am having trouble controlling the way the data is being displayed.
At first I tried using the regular implicit synchronization by doing:
angularFire(ref, $scope, 'items');
It worked fine and all the data was displayed when I used the model $items in my view. However, when the data is arriving from the Firebase data source it is not formatted in a way that the view supports, so I need to do some additional structural changes to the data before it is displayed. Problem is, I won't know when the data has been fully loaded. I tried assigning a $watch to the $items, but it was called too early.
So, I moved on and tried to use the angularfireCollection instead:
$scope.items = angularFireCollection(new Firebase(url), optionalCallbackOnInitialLoad);
The documentation isn't quite clear what the "optionalCallbackOnInitialLoad" does and when it is called, but trying to access the first item in the $items collection will throw an error ("Uncaught TypeError: Cannot read property '0' of undefined").
I tried adding a button and in the button's click handler I logged the content of the first item in the $items, and it worked:
console.log($scope.items[0]);
There it was! The first object from my Firebase was displayed without any errors ... only problem is that I had to click a button to get there.
So, does anyone know how I can know when all the data has been loaded and then assign it to a $scope variable to be displayed in my view? Or is there another way?
My controller:
app.controller('MyController', ['$scope', 'angularFireCollection',
function MyController($scope, angularFireCollection) {
$scope.start = function()
{
var ref = new Firebase('https://url.firebaseio.com/days');
console.log("start");
console.log("before load?");
$scope.items = angularFireCollection(ref, function()
{
console.log("loaded?");
console.log($scope.items[0]); //undefined
});
console.log("start() out");
};
$scope.start();
//wait for changes
$scope.$watch('items', function() {
console.log("items watch");
console.log($scope.items[0]); //undefined
});
$scope.testData = function()
{
console.log($scope.items[0].properties); //not undefined
};
}
]);
My view:
<button ng-click="testData()">Is the data loaded yet?</button>
Thanks in advance!
So, does anyone know how I can know when all the data has been loaded
and then assign it to a $scope variable to be displayed in my view? Or
is there another way?
Remember that all Firebase calls are asynchronous. Many of your problems are occurring because you're trying to access elements that don't exist yet. The reason the button click worked for you is because you clicked the button (and accessed the elements) after they had been successfully loaded.
In the case of the optionalCallbackOnInitialLoad, this is a function that will be executed once the initial load of the angularFireCollection is finished. As the name implies, it's optional, meaning that you don't have to provide a callback function if you don't want to.
You can either use this and specify a function to be executed after it's loaded, or you can use $q promises or another promise library of your liking. I'm partial to kriskowal's Q myself. I'd suggest reading up a bit on asynchronous JavaScript so you get a deeper understanding of some of these issues.
Be wary that this:
$scope.items = angularFireCollection(ref, function()
{
console.log("loaded?");
console.log($scope.items[0]); //undefined
});
does correctly specify a callback function, but $scope.items doesn't get assigned until after you've ran the callback. So, it still won't exist.
If you just want to see when $scope.items has been loaded, you could try something like this:
$scope.$watch('items', function (items) {
console.log(items)
});
In my project I needed to know too when the data has been loaded. I used the following approach (implicit bindings):
$scope.auctionsDiscoveryPromise = angularFire(firebaseReference.getInstance() + "/auctionlist", $scope, 'auctionlist', []);
$scope.auctionsDiscoveryPromise.then(function() {
console.log("AuctionsDiscoverController auctionsDiscoveryPromise resolved");
$timeout(function() {
$scope.$broadcast("AUCTION_INIT");
}, 500);
}, function() {
console.error("AuctionsDiscoverController auctionsDiscoveryPromise rejected");
});
When the $scope.auctionsDiscoveryPromise promise has been resolved I'm broadcasting an event AUCTION_INIT which is being listened in my directives. I use a short timeout just in case some services or directives haven't been initialized yet.
I'm using this if it would help anyone:
function getAll(items) {
var deferred = $q.defer();
var dataRef = new Firebase(baseUrl + items);
var returnData = angularFireCollection(dataRef, function(data){
deferred.resolve(data.val());
});
return deferred.promise;
}
I am looking for a way to execute code when after I add changes to a $scope variable, in this case $scope.results. I need to do this in order to call some legacy code that requires the items to be in the DOM before it can execute.
My real code is triggering an AJAX call, and updating a scope variable in order to update the ui. So I currently my code is executing immediately after I push to the scope, but the legacy code is failing because the dom elements are not available yet.
I could add an ugly delay with setTimeout(), but that doesn't guarantee that the DOM is truly ready.
My question is, is there any ways I can bind to a "rendered" like event?
var myApp = angular.module('myApp', []);
myApp.controller("myController", ['$scope', function($scope){
var resultsToLoad = [{id: 1, name: "one"},{id: 2, name: "two"},{id: 3, name: "three"}];
$scope.results = [];
$scope.loadResults = function(){
for(var i=0; i < resultsToLoad.length; i++){
$scope.results.push(resultsToLoad[i]);
}
}
function doneAddingToDom(){
// do something awesome like trigger a service call to log
}
}]);
angular.bootstrap(document, ['myApp']);
Link to simulated code: http://jsfiddle.net/acolchado/BhApF/5/
Thanks in Advance!
The $evalAsync queue is used to schedule work which needs to occur outside of current stack frame, but before the browser's view render. -- http://docs.angularjs.org/guide/concepts#runtime
Okay, so what's a "stack frame"? A Github comment reveals more:
if you enqueue from a controller then it will be before, but if you enqueue from directive then it will be after. -- https://github.com/angular/angular.js/issues/734#issuecomment-3675158
Above, Misko is discussing when code that is queued for execution by $evalAsync is run, in relation to when the DOM is updated by Angular. I suggest reading the two Github comments before as well, to get the full context.
So if code is queued using $evalAsync from a directive, it should run after the DOM has been manipulated by Angular, but before the browser renders. If you need to run something after the browser renders, or after a controller updates a model, use $timeout(..., 0);
See also https://stackoverflow.com/a/13619324/215945, which also has an example fiddle that uses $evalAsync().
I forked your fiddle.
http://jsfiddle.net/xGCmp/7/
I added a directive called emit-when. It takes two parameters. The event to be emitted and the condition that has to be met for the event to be emitted. This works because when the link function is executed in the directive, we know that the element has been rendered in the DOM. My solution is to emit an event when the last item in the ng-repeat has been rendered.
If we had an all Angular solution, I would not recommend doing this. It is kind of hacky. But, it might be an okey solution for handling the type of legacy code that you mention.
var myApp = angular.module('myApp', []);
myApp.controller("myController", ['$scope', function($scope){
var resultsToLoad = [
{id: 1, name: "one"},
{id: 2, name: "two"},
{id: 3, name: "three"}
];
function doneAddingToDom() {
console.log(document.getElementById('renderedList').children.length);
}
$scope.results = [];
$scope.loadResults = function(){
$scope.results = resultsToLoad;
// If run doneAddingToDom here, we will find 0 list elements in the DOM. Check console.
doneAddingToDom();
}
// If we run on doneAddingToDom here, we will find 3 list elements in the DOM.
$scope.$on('allRendered', doneAddingToDom);
}]);
myApp.directive("emitWhen", function(){
return {
restrict: 'A',
link: function(scope, element, attrs) {
var params = scope.$eval(attrs.emitWhen),
event = params.event,
condition = params.condition;
if(condition){
scope.$emit(event);
}
}
}
});
angular.bootstrap(document, ['myApp']);
Using timeout is not the correct way to do this. Use a directive to add/manipulate the DOM. If you do use timeout make sure to use $timeout which is hooked into Angular (for example returns a promise).
If you're like me, you'll notice that in many instances $timeout with a wait of 0 runs well before the DOM is truly stable and completely static. When I want the DOM to be stable, I want it to be stable gosh dang it. And so the solution I've come across is to set a watcher on the element (or as in the example below the entire document), for the "DOMSubtreeModified" event. Once I've waited 500 milliseconds and there have been no DOM changes, I broadcast an event like "domRendered".
IE:
//todo: Inject $rootScope and $window,
//Every call to $window.setTimeout will use this function
var broadcast = function () {};
if (document.addEventListener) {
document.addEventListener("DOMSubtreeModified", function (e) {
//If less than 500 milliseconds have passed, the previous broadcast will be cleared.
clearTimeout(broadcast)
broadcast = $window.setTimeout(function () {
//This will only fire after 500 ms have passed with no changes
$rootScope.$broadcast('domRendered')
}, 500)
});
//IE stupidity
} else {
document.attachEvent("DOMSubtreeModified", function (e) {
clearTimeout(broadcast)
broadcast = $window.setTimeout(function () {
$rootScope.$broadcast('domRendered')
}, 500)
});
}
This event can be hooked into, like all broadcasts, like so:
$rootScope.$on("domRendered", function(){
//do something
})
I had a custom directive and I needed the resulting height() property of the element inside my directive which meant I needed to read it after angular had run the entire $digest and the browser had flowed out the layout.
In the link function of my directive;
This didn't work reliably, not nearly late enough;
scope.$watch(function() {});
This was still not quite late enough;
scope.$evalAsync(function() {});
The following seemed to work (even with 0ms on Chrome) where curiously even ẁindow.setTimeout() with scope.$apply() did not;
$timeout(function() {}, 0);
Flicker was a concern though, so in the end I resorted to using requestAnimationFrame() with fallback to $timeout inside my directive (with appropriate vendor prefixes as appropriate). Simplified, this essentially looks like;
scope.$watch("someBoundPropertyIexpectWillAlterLayout", function(n,o) {
$window.requestAnimationFrame(function() {
scope.$apply(function() {
scope.height = element.height(); // OK, this seems to be accurate for the layout
});
});
});
Then of course I can just use a;
scope.$watch("height", function() {
// Adjust view model based on new layout metrics
});
interval works for me,for example:
interval = $interval(function() {
if ($("#target").children().length === 0) {
return;
}
doSomething();
$interval.cancel(interval);
}, 0);
Currently I have an Angular.js page that allows searching and displays results. User clicks on a search result, then clicks back button. I want the search results to be displayed again but I can't work out how to trigger the search to execute. Here's the detail:
My Angular.js page is a search page, with a search field and a search
button. The user can manually type in a query and press a button and
and ajax query is fired and the results are displayed. I update the URL with the search term. That all works fine.
User clicks on a result of the search and is taken to a different page - that works fine too.
User clicks back button, and goes back to my angular search page, and the correct URL is displayed, including the search term. All works fine.
I have bound the search field value to the search term in the URL, so it contains the expected search term. All works fine.
How do I get the search function to execute again without the user having to press the "search button"? If it was jquery then I would execute a function in the documentready function. I can't see the Angular.js equivalent.
On the one hand as #Mark-Rajcok said you can just get away with private inner function:
// at the bottom of your controller
var init = function () {
// check if there is query in url
// and fire search in case its value is not empty
};
// and fire it after definition
init();
Also you can take a look at ng-init directive. Implementation will be much like:
// register controller in html
<div data-ng-controller="myCtrl" data-ng-init="init()"></div>
// in controller
$scope.init = function () {
// check if there is query in url
// and fire search in case its value is not empty
};
But take care about it as angular documentation implies (since v1.2) to NOT use ng-init for that. However imo it depends on architecture of your app.
I used ng-init when I wanted to pass a value from back-end into angular app:
<div data-ng-controller="myCtrl" data-ng-init="init('%some_backend_value%')"></div>
Try this?
$scope.$on('$viewContentLoaded', function() {
//call it here
});
I could never get $viewContentLoaded to work for me, and ng-init should really only be used in an ng-repeat (according to the documentation), and also calling a function directly in a controller can cause errors if the code relies on an element that hasn't been defined yet.
This is what I do and it works for me:
$scope.$on('$routeChangeSuccess', function () {
// do something
});
Unless you're using ui-router. Then it's:
$scope.$on('$stateChangeSuccess', function () {
// do something
});
angular.element(document).ready(function () {
// your code here
});
Dimitri's/Mark's solution didn't work for me but using the $timeout function seems to work well to ensure your code only runs after the markup is rendered.
# Your controller, including $timeout
var $scope.init = function(){
//your code
}
$timeout($scope.init)
Hope it helps.
You can do this if you want to watch the viewContentLoaded DOM object to change and then do something. using $scope.$on works too but differently especially when you have one page mode on your routing.
$scope.$watch('$viewContentLoaded', function(){
// do something
});
You can use angular's $window object:
$window.onload = function(e) {
//your magic here
}
Another alternative:
var myInit = function () {
//...
};
angular.element(document).ready(myInit);
(via https://stackoverflow.com/a/30258904/148412)
Yet another alternative if you have a controller just specific to that page:
(function(){
//code to run
}());
When using $routeProvider you can resolve on .state and bootstrap your service. This is to say, you are going to load Controller and View, only after resolve your Service:
ui-routes
.state('nn', {
url: "/nn",
templateUrl: "views/home/n.html",
controller: 'nnCtrl',
resolve: {
initialised: function (ourBootstrapService, $q) {
var deferred = $q.defer();
ourBootstrapService.init().then(function(initialised) {
deferred.resolve(initialised);
});
return deferred.promise;
}
}
})
Service
function ourBootstrapService() {
function init(){
// this is what we need
}
}
Found Dmitry Evseev answer quite useful.
Case 1 : Using angularJs alone:
To execute a method on page load, you can use ng-init in the view and declare init method in controller, having said that use of heavier function is not recommended, as per the angular Docs on ng-init:
This directive can be abused to add unnecessary amounts of logic into your templates. There are only a few appropriate uses of ngInit, such as for aliasing special properties of ngRepeat, as seen in the demo below; and for injecting data via server side scripting. Besides these few cases, you should use controllers rather than ngInit to initialize values on a scope.
HTML:
<div ng-controller="searchController()">
<!-- renaming view code here, including the search box and the buttons -->
</div>
Controller:
app.controller('SearchCtrl', function(){
var doSearch = function(keyword){
//Search code here
}
doSearch($routeParams.searchKeyword);
})
Warning : Do not use this controller for another view meant for a different intention as it will cause the search method be executed there too.
Case 2 : Using Ionic:
The above code will work, just make sure the view cache is disabled in the route.js as:
route.js
.state('app', {
url : '/search',
cache : false, //disable caching of the view here
templateUrl : 'templates/search.html' ,
controller : 'SearchCtrl'
})
Hope this helps
I had the same problem and only this solution worked for me (it runs a function after a complete DOM has been loaded). I use this for scroll to anchor after page has been loaded:
angular.element(window.document.body).ready(function () {
// Your function that runs after all DOM is loaded
});
You can save the search results in a common service which can use from anywhere and doesn't clear when navigate to another page, and then you can set the search results with the saved data for the click of back button
function search(searchTerm) {
// retrieve the data here;
RetrievedData = CallService();
CommonFunctionalityService.saveSerachResults(RetrievedData);
}
For your backbutton
function Backbutton() {
RetrievedData = CommonFunctionalityService.retrieveResults();
}
call initial methods inside self initialize function.
(function initController() {
// do your initialize here
})();