Problem: The attribute I pass to my directive's controller is not evaluated. For example, I get {{ attribute.value }} instead of 5.
Desired Outcome: My directive's controller has access to a primary key contained in an object from a parent controller. I need it to make API calls like MyResource.save({id: attribute});.
Code Snippets:
Calling directive from HTML
<div ng-controller="BoatDetailController as boatCtrl">
<div class="row">
<booking-widget boat-id="{{ boatCtrl.boat.id }}"></booking-widget>
</div>
Directive
(function () {
'use strict';
angular.
module('trips').
directive('bookingWidget', bookingWidget);
bookingWidget.$inject = [];
function bookingWidget() {
return {
restrict: 'E',
scope: {
boatId: '#'
},
templateUrl: "/static/app/trips/trips.bookingwidget.template.html",
controller: 'BookingWidgetController as bookingCtrl'
}
}
})();
Controller
(function () {
'use strict';
angular.
module('trips').
controller('BookingWidgetController', BookingWidgetController);
BookingWidgetController.$inject = ['Trip', 'Booking', 'Messages', '$scope', '$attrs'];
function BookingWidgetController(Trip, Booking, Messages, $scope, $attrs) {
var vm = this;
vm.boatId = $attrs.boatId;
...
activate();
//////////////////////////////
function activate() {
console.log(vm.boatId);
//
}
Console Results:
With $scope.boatId: (logs a blank line)
With $attrs.boatId: {{ boatCtrl.boat.id }} (a string)
Recap: The boat-id attribute of my directive is not resolving. Can you help me figure out how to fix it?
You can actually create a custom directive like this:
function bookingWidget() {
return {
restrict: 'E',
scope: {
boatId: '#'
},
templateUrl: "/static/app/trips/trips.bookingwidget.template.html",
controller: 'BookingWidgetController as bookingCtrl',
link : function(scope, element, attrs, controller){
console.log(attrs.boatId);
scope.boatId = attrs.boatId;
}
}
}
The link function actually allows you to have an access to the element, the scope of the directive, the attributes associated to the directive and the controller of the directive. The function is called after everything associated to the directive has been performed. In other words, this is the last stage.
The same scope would be shareable between the link function and controller.
Now, to make the API call, you may actually add a function in your controller that accepts the boatID, makes a call to the API and accepts the response onto the controller object. After that, add a watcher within the link function that watches over "vm.boatId", within which you may call that function which makes the API call. So, even if the controller has initialized before the link function, you would still be able to perform what you wish to. So, it would be a "link-based activation".
You may give this solution a try. Hope it helps.
You can pass a function and call it. Need to use & then.
https://thinkster.io/egghead/isolate-scope-am
Related
Im learning about Angular directives and I can't wrap my head around the scope topic. Suppose I have this custom directive which is named parentDirective. It has a controller property and a link property, as follows:
angular.module("app").directive("parentDirective", function () {
return {
restrict: "E",
templateUrl: "dirs/parent.html",
scope:{
character: "="
},
controller: function ($scope) {
$scope.getData = function (data) {
console.log(data);
}
},
link: function (scope,elem, attrs) {
elem.bind("click", function (e) {
//get object here?
});
scope.getData = function (data) {
console.log(data);
}
}
}
});
Its template is defined as follows:
<p ng-click="getData(character)">
{{character.name}}
</p>
I can get the character object in the controller function through the $scope variable and I have access to the same data in the link function through scope. Whats the difference between the two methods in this regard? Second question, Is it possible to bind a click to the directive and get the object like this:
elem.bind("click", function (e) {
//get object here?
});
Scope is specific to current directive instance and is the same object in both functions.
For defining methods on the scope, there's no difference if they are defined in controller or link function, unless there is race condition that requires the method to be defined as early as possible. For this reason it makes sense to define scope methods in controller.
Event handler doesn't differ from any other function, it is
elem.on("click", function (e) {
scope.$apply(function () {
scope.character...
});
});
scope.$apply(...) wrapper doesn't hurt anyway, but the necessity of it depends on what happens with scope.character.
The directive can have only controller and no link. Current Angular versions (1.5+) suggest the style where bindToController + controllerAs are used instead of scope bindings as common ground for directives and components.
Then the directive may look like
restrict: "E",
template: '<p>{{$ctrl.character.name}}</p>',
controllerAs: '$ctrl',
bindToController: { character: "=" },
controller: function ($element, $scope) {
var self = this;
self.getData = function (data) { ... };
$element.on("click", function (e) {
scope.$apply(function () {
self.character...
});
});
}
link function may appear as $postLink controller hook, but here it is not needed.
The problem
I am unit testing a directive has no controller or template, only a link function. The directive requires ngModel and calls one of its functions in the link function. I want to spy on ngModel in my unit tests to ensure the right function is being called.
The code
Directive:
angular.module('some-module').directive('someDirective', function() {
return {
restrict: 'A',
require: 'ngModel',
link: function(scope, element, attr, controller) {
controller.doSomething(); //Calls some random function on the ngModel controller
}
};
});
What I've tried
I've tried to inject a spy ngModel like this:
beforeEach(module(function($provide) {
$provide.factory('ngModelDirective', function() {
return {};
});
$provide.factory('ngModelController', function() {
return function() {};
});
}));
As I discovered on this question, trying to override built-in properties causes an error to be thrown, and is bad practice.
So then I tried to test the directive the way the Angular docs say to:
var $scope = $rootScope.$new();
var element = $compile('<div some-directive></div>')($scope);
And spy on NgModelController like this:
var ngModelControllerSpyDoSomething = sinon.spy(element.controller('ngModel'), 'doSomething');
But this doesn't work, because one $compile is run, it executes the link function, so I'm not spying on it until it's too late (the spy is coming back as never having been called). This is also the case if I put $scope.$digest(); before or after creating the spy.
You will have to add your spy to the $scope you are injecting into the $compile-Function and then link it within the actual directives HTMLngModel`, so:
var $scope = $rootScope.$new();
$scope.mySpy = // create a stub function with sinon here
var element = $compile('<div some-directive ng-model="mySpy"></div>')($scope);
JQuery to Directive
I want to call a method from the scope of this directive but can't seem to work it out (if possible).
$("my-directive").first().scope().loadData();
Directive Looks Something Like This
I would like to call the loadData function from the directive code below.
app.directive("myDirective", function () {
return {
restrict: "E",
templateUrl: "..."
scope: {},
controller: function ($scope, $element, $attrs) {
var self = this;
$scope.loadData = function () {
...
};
}
};
});
Scope is accessible inside the directive
You can get any child of the element of which directive is applied and get scope of it.
$('my-directive').first().children(":first").scope().loadData()
Strajk's answer is correct!
When Code is Added Dynamically setTimeout Needed
In the following example detail row has a nested directive (random-testees). I get the scope from that to dynamically compile the directive (dynamic and late-bound). The setTimeout is needed because it seems to take a bit before the
var detailRow = e.detailRow;
// Compile the directive for dyanmic content.
angular.element(document).injector().invoke(function ($compile) {
var scope = angular.element(detailRow).scope();
$compile(detailRow)(scope);
});
// Get some data from directive.
var testId = detailRow.find("random-testees").attr("testid");
// Wait, and call method on the directive.
setTimeout(function () {
var randomTesteesScope = $("random-testees").first().children(":first").scope();
randomTesteesScope.loadTestees(this);
}.bind(testId),200);
Not Very Confident About This
This seems a little brittle since I was getting mixed results with a 100 ms timeout sometimes and error when the randomTesteesScope returned undefined.
I am developing a directive which shows and hides it's contents based on a click event (ng-click) defined in it's template. On some views where the directive is used I'd like to be able to know if the directive is currently showing or hiding it's contents so I can respond to the DOM changes. The directive has isolated scope and I am trying to notify the parent scope when the directive has been "toggled". I'm attempting to accomplish this by passing a callback function to the directive where it is used that can be called when the directive's state changes i.e hides or shows
I'm not sure how to correctly implement this being that the state of the directive (hidden or shown) is stored in the directive's isolated scope and is determined after the ng-click. Therefore I need to call the parent scope's function from within the directive and not from withing the view.
This will make WAAY more sense with an example. Here is a plunked demonstrating what I'd like to do:
http://plnkr.co/edit/hHwwxjssOKiphTSO1VIS?p=info
var app = angular.module('main-module',[])
app.controller('MainController', function($scope){
$scope.myValue = 'test value';
$scope.parentToggle = function(value){
$scope.myValue = value;
};
});
app.directive('toggle', function(){
return {
restrict: 'A',
template: '<a ng-click="toggle();">Click Me</a>',
replace: true,
scope: {
OnToggle: '&'
},
link: function($scope, elem, attrs, controller) {
$scope.toggleValue = false;
$scope.toggle = function () {
$scope.toggleValue = !$scope.toggleValue;
$scope.OnToggle($scope.toggleValue)
};
}
};
});
I'm relatively new to Angular. Is this a bad idea to begin with? Should I be using a service or something rather than passing around function refs?
Thanks!
Update
You can also use & to bind the function of the root scope (that is actually the purpose of &).
To do so the directive needs to be slightly changed:
app.directive('toggle', function(){
return {
restrict: 'A',
template: '<a ng-click="f()">Click Me</a>',
replace: true,
scope: {
toggle: '&'
},
controller: function($scope) {
$scope.toggleValue = false;
$scope.f = function() {
$scope.toggleValue = !$scope.toggleValue;
$scope.toggle({message: $scope.toggleValue});
};
}
};
});
You can use like this:
<div toggle="parentToggle(message)"></div>
Plunk
You could bind the function using =. In addition ensure the property name in your scope and tag are matching (AngularJS translates CamelCase to dash notation).
Before:
scope: {
OnToggle: '&'
}
After:
scope: {
onToggle: '='
}
Furthermore don't use on-toggle="parentToggle({value: toggleValue})" in your main template. You do not want to call the function but just passing a pointer of the function to the directive.
Plunk
Problem
Dynamically add the ng-bind attribute through a custom directive to be able to use ng-bind, ng-bind-html or ng-bind-html-unsafe in a custom directive with out manually adding to the template definition everywhere.
Example
http://jsfiddle.net/nstuart/hUxp7/2/
Broken Directive
angular.module('app').directive('bindTest', [
'$compile',
function ($compile) {
return {
restrict: 'A',
scope: true,
compile: function (tElem, tAttrs) {
if (!tElem.attr('ng-bind')) {
tElem.attr('ng-bind', 'content');
$compile(tElem)
}
return function (scope, elem, attrs) {
console.log('Linking...');
scope.content = "Content!";
};
}
};
}]);
Solution
No idea. Really I can not figure out why something like the above fiddle doesn't work. Tried it with and with out the extra $compile in there.
Workaround
I can work around it might adding a template value in the directive, but that wraps the content in an extra div, and I would like to be able to that if possible. (See fiddle)
Second Workaround
See the fiddle here: http://jsfiddle.net/nstuart/hUxp7/4/ (as suggested by Dr. Ikarus below). I'm considering this a workaround for right now, because it still feels like you should be able to modify the template before you get to the linking function and the changes should be found/applied.
You could do the compiling part inside the linking function, like this:
angular.module('app').directive('bindTest', ['$compile', function ($compile) {
return {
restrict: 'A',
scope: true,
link: {
post: function(scope, element, attrs){
if (!element.attr('ng-bind')) {
element.attr('ng-bind', 'content');
var compiledElement = $compile(element)(scope);
}
console.log('Linking...');
scope.content = "Content!";
}
}
};
}]);
Let me know how well this worked for you http://jsfiddle.net/bPCFj/
This way seems more elegant (no dependency with $compile) and appropriate to your case :
angular.module('app').directive('myCustomDirective', function () {
return {
restrict: 'A',
scope: {},
template: function(tElem, tAttrs) {
return tAttrs['ng-bind'];
},
link: function (scope, elem) {
scope.content = "Happy!";
}
};
});
jsFiddle : http://jsfiddle.net/hUxp7/8/
From Angular directive documentation :
You can specify template as a string representing the template or as a function which takes two arguments tElement and tAttrs (described in the compile function api below) and returns a string value representing the template.
The source code tells all! Check out the compileNodes() function and its use of collectDirectives().
First, collectDirectives finds all the directives on a single node. After we've collected all the directives on that node, then the directives are applied to the node.
So when your compile function on the bindTest directive executes, the running $compile() is past the point of collecting the directives to compile.
The extra call to $compile in your bindTest directive won't work because you are not linking the directive to the $scope. You don't have access to the $scope in the compile function, but you can use the same strategy in a link function where you do have access to the $scope
You guys were so close.
function MyDirective($compile) {
function compileMyDirective(tElement) {
tElement.attr('ng-bind', 'someScopeProp');
return postLinkMyDirective;
}
function postLinkMyDirective(iScope, iElement, iAttrs) {
if (!('ngBind' in iAttrs)) {
// Before $compile is run below, `ng-bind` is just a DOM attribute
// and thus is not in iAttrs yet.
$compile(iElement)(iScope);
}
}
var defObj = {
compile: compileMyDirective,
scope: {
someScopeProp: '=myDirective'
}
};
return defObj;
}
The result will be:
<ANY my-directive="'hello'" ng-bind="someScopeProp">hello</ANY>