Isolated scope: value not updating - angularjs

I am trying to expand on the bootstrap ui library with my own custom control. This control will be used in an AngularJS app. Currently, I'm getting stuck on the scoping.
My plunker is here
This plunker is a simplified version of a more complex control. The concept that I'm trying to highlight is the scoping. You will notice that the custom control, my-query, is pre-populated with the value of myController.$scope.query. You will also see that the query is put in the page underneath the custom control. As I type, the value does NOT get updated. Why? My code looks like the following:
myApp.directive('myQuery', [function() {
return {
restrict:'E',
transclude: true,
scope: {
query: '='
},
template: '<div ng-controller="myQueryController"><input type="text" ng-model="query" /><button ng-click="go_Click()">go</button></div>'
};
}]);
myApp.controller('myQueryController', ['$scope', function($scope) {
$scope.go_Click = function() {
$scope.$emit("goClicked");
};
}]);
What am I doing wrong?

In your directive template, you are adding an additional controller which is adding in another scope. That is what is causing the problem. Instead of doing it that way, move the controller logic into either a controller function or a link function defined on your directive, either will work.
Try this. Here's an example using a controller function. Note that I moved your original myQueryController inside the directive and removed the ng-controller directive from the myQuery directive's template.
'use strict';
var myApp = angular.module('myApp', []);
myApp.controller('myController', ['$scope', function($scope) {
$scope.queryValue = 'test';
$scope.$on('goClicked', function() {
$scope.performAction();
});
$scope.performAction = function() {
alert('Using ' + $scope.queryValue);
};
}]);
myApp.directive('myQuery', [function() {
return {
restrict:'E',
transclude: true,
scope: {
query: '='
},
template: '<div><input type="text" ng-model="query" /><button ng-click="go_Click()">go</button></div>',
controller : function ($scope) {
$scope.go_Click = function() {
$scope.$emit("goClicked");
};
}
};
}]);

<div ng-controller="myQueryController">
A controller creates a new scope. So <input type="text" ng-model="query" /> doesn't use query from the directive's scope but from the controller's scope. Instead of using a controller you can define the go_Clickfunction in the directive's link method.

Do you need this?:
http://plnkr.co/edit/6IrlnXvsi2Rneee0hGC8?p=preview
scope: {
model: '='
}
The problem was that you used a primitive type which was passed by value into your directive. Always use complex types which are passed by reference.

Related

angularjs: can' t pass parameter to the parent controller method via '&' binding in isolated directive scope

In my angular application, I defined a directive foo-directive, which is placed in a parent controller as below:
<div ng-app="app">
<div ng-controller="ParentCtrl as parent">
<foo-directive data="parent.city" tab-click="parent.tClick()" tab-click2="parent.tClick2(v)"></foo-directive>
</div>
</div>
pass two method: parent.tClick() and parent.tClick2(v) into the directive and bind to tab-click and tab-click2 attributes respectively. The difference is that the second one has a parameter
and the JS code goes as below:
function ParentCtrl($timeout){
this.city= "London";
this.tClick = function(){
console.log("debugging parent tclick...");
}
this.tClick2 = function(v){
console.log("debugging parent tclick2...");
console.log(v)
}
}
function FirstCtrl() {
this.$onInit = function(){
this.click = function(){
this.tabClick();
this.tabClick2("abc");
}
}
}
function fooDirective() {
return {
scope: {
data: '=',
tabClick : "&",
tabClick2: "&"
},
controller: 'FirstCtrl',
controllerAs: 'foo',
bindToController: true,
template: '<div ng-click="foo.click()">{{ foo.data }}</div>',
link: function ($scope, $element, $attrs, $ctrl) {
//console.log($ctrl.name);
}
};
}
Now the issue comes from the second method this.tabClick2("abc"). There is TypeError message. I have reproduced this issue with this live demo:
https://jsfiddle.net/baoqger/sv4d03hk/1/
any help?
When passing the functions into your directive, you should pass the "reference" to the function, rather than the "result" of the function. Adding the parenthesis, is actually executing the function and returning the result to the directive. As neither function returns a value, they will both be passing undefined.
Given that the value of the parameter you want to pass (v) to the function is inside the directive scope, not that of the parent, you dont need to even tell the directive that the function accepts a parameter. You just pass it to the function inside the directive. ie.
<foo-directive data="parent.city" tab-click="parent.tClick" tab-click2="parent.tClick2"></foo-directive>
According to the docs, using & is then you want to evaluate the result of the attribute:
The & binding allows a directive to trigger evaluation of an expression in the context of the original scope, at a specific time.
Instead, we want to be able to execute the passed attribute, and in particular give it a variable. As such either = (two-way binding) or # (one-way binding) are probably more appropriate for what we're after.
tabClick: "=",
tabClick2: "="
You can also do away with your controller completely by updating your template.
template: '<div ng-click="foo.tabClick();foo.tabClick2(data)">{{ foo.data }}</div>'
Updated JSFiddle
function ParentCtrl($timeout) {
this.city = "London";
this.tClick = function() {
console.log("debugging parent tclick...");
}
}
function FirstCtrl() {}
function fooDirective() {
return {
scope: {
data: '=',
tabClick: "="
},
controller: 'FirstCtrl',
controllerAs: 'foo',
bindToController: true,
template: '<div ng-click="foo.tabClick(data)">{{ foo.data }}</div>',
link: function($scope, $element, $attrs, $ctrl) {
//console.log($ctrl.name);
}
};
}
angular
.module('app', [])
.directive('fooDirective', fooDirective)
.controller('FirstCtrl', FirstCtrl)
.controller('ParentCtrl', ParentCtrl)
<script src="https://code.angularjs.org/1.6.2/angular.min.js"></script>
<div ng-app="app">
<div ng-controller="ParentCtrl as parent">
<foo-directive data="parent.city" tab-click=":: parent.tClick"></foo-directive>
</div>
</div>
PS. if you're concerned about performance using # or =, consider one time bindings using ::. ie. <foo-directive data="parent.city" tab-click=":: parent.tClick" tab-click2=":: parent.tClick2"></foo-directive>
Try the following snippet of code for your "FirstCtrl":
function FirstCtrl() {
this.$onInit = function(){
this.click = function(){
this.tabClick({v: this.data});
}
}
}
As you are using an expression binding (&), you need to explicitly call it with a JSON containing "v" and it's value. like the following:
this.tabClick({v: this.data});

Is it possible to pass in a custom controller into custom directive?

Is it possible to pass in a custom controller into custom directive to be able to use the custom directive on the page with different controllers?
I can't find a solution for that on docs.angularjs.org
[Edited]
Let's say we have the following directive's defenition:
angular.module('myApp', [])
.controller('myDirectiveController', function ($scope) {
$scope.name = 'there, dude';
})
.directive('myDirective', function () {
return {
restrict: 'E',
replace: true,
template: '<div>Hello {{name}}!</div>',
controller: 'myDirectiveController' // can i overwrite it outside this code?
};
});
Can I simply overwrite the directive's controller not touching the directive's source code itself?
Use custom controller with one HTML template
Then pass your data from that page to directive.
and use that data in HTML template which is assign in directive or also you can write controller in your directive.
.controller('myController', function () {
// write business logic here
// take some data which you want to use in directive
});
Then pass it through HTML to directive
Use that data in,
.directive('dir', function () {
return {
scope: {
// collect your data and use it in link
}
};
});
Perhaps instead of defining the controller in the directive like you have, you can put it in the html template like:
.directive('myDirective', function () {
return {
restrict: 'E',
replace: true,
scope: {
ctrl: '='
},
template: '<div ng-controller="{{ctrl}}">Hello {{name}}!</div>'
};
});
Then I think you will be able to use the directive like:
<my-directive ctrl="myDirectiveController"></my-directive>

Access isolated scope in angular directive template

I am currently writing an angular directive that uses a template in a different HTML file and an isolated template. The directive gets some string via # to its scope and that value is available in teh controller function.
Somehow its not available via {{}} in the HTML template. Why is that so? How can I change that? I read something about the template using the parent scope but I don't fully understand that.
Here is a code example:
angular.module('moduleName')
.directive('aGreatDirective', function () {
return {
restrict: 'E',
scope: {
mapid: '#'
},
templateUrl: "path/to/template.html",
controller: ['$scope', function (scope) {
console.log($scope.mapid); // is defined
}
}
});
And the html code for the template:
<div id="{{mapid}}"></div>
The result in the browser is exactly the same where it should be:
<div id="theValueOfmapid"></div>
Thanks for your help!
PS Here is a jsfiddle: fiddle
Your fiddle was incorrect since you didn't have your controller defined or $scope injected properly. The following will work just fine:
template:
<div ng-controller="MyCtrl">
<a-great-directive mapid="thisisthemapid"></a-great-directive>
Some other code
</div>
js:
var myApp = angular.module('myApp', []);
myApp.controller('MyCtrl', function () {
});
myApp.directive('aGreatDirective', function() {
return {
restrict: 'E',
scope: {
mapid: '#'
},
template: "<div id='{{mapid}}'> {{mapid}} </div>",
controller: ['$scope', function($scope) {
console.log($scope.mapid); // is defined
}
]}
});
Fiddle
Note that in my example, the injected variable in your directive's controller should be $scope, not scope, for consistency reasons.

AngularJS can't pass in different function when directive coupled with controller

I have a directive which I want to tightly couple with a controller as a component. I assumed I was following best practice by explicitly passing ion my functions even though I was declaring the controller to use. Here is an example:
app.js
var app = angular.module('plunker', [])
app
.controller('myCtrl', function($scope) {
$scope.output = '';
$scope.foo = function () {
$scope.output = 'foo';
}
$scope.bar = function () {
$scope.output = 'bar';
}
})
.directive('myDirective', function() {
return {
scope: {
output: '=',
foo: '&',
},
templateUrl: 'template.html',
replace: true,
controller: 'myCtrl',
};
})
template.html
<div>
<button ng-click="foo()">Click Foo</button>
<p>You clicked: <span style="color:red">{{output}}</span></p>
</div>
index.html
<body>
<my-directive
output="output"
foo="bar()"> <!-- pass in the *bar* function instead of the *foo* function -->
</my-directive>
</body>
Plunkr: http://plnkr.co/edit/Y4lhxuXbK9YbjAklR7v1?p=preview
Here, even though I'm passing in the bar() function, the output is 'foo' when the button is clicked. If I uncouple the controller by commenting out controller: 'myCtrl' in the directive, the output becomes 'bar'.
I thought I could declare the controller but still be free to pass in which functions I desire to the directive. It also seems that explicitly passing these functions in is a little redundant if the directive just looks up to the controller to find it (I can pass nothing into the directive and it still works).
This is especially problematic when testing as I would like to pass in my own stub functions to the directive, which at the moment I cannot do.
Is there some way to achieve what I want or am I doing something fundamentally wrong?
EDIT I meant to not have the controller declared in the HTML.
Remove the controller property on the directive:
.directive('myDirective', function() {
return {
scope: {
output: '=',
foo: '&',
},
templateUrl: 'template.html',
replace: true,
// controller: 'myCtrl',
};
})
You're wiring up the same controller to the directive as the parent, which is overwriting all the properties you're trying to pass in via isolate scope. The controller is wired up twice, once on the parent scope and then again on the directive. Removing this will allow you to pass in the function bar() and it will not be overwritten.
Here's the Plunker Demonstration
When running inside a directive, the $scope is initialized with output and foo variables before the controller constructor is called. Your controller is essentially overwriting these properties.
A simple check in your controller
if(!$scope.foo)
{
$scope.foo = function () {
$scope.output = 'foo';
}
}
Would work.
PS. I'm assuming your example is a simplification of your problem. If it's not, then the other answer's advice to simply remove the controller from the directive is the best approach.

Directive - controller data binding in AngularJS

I'm struggling with this for hours now.
var testApp = angular.module('testApp', []);
testApp.directive('test', function() {
return {
restrict: 'E',
transclude: true,
template: '<div ng-transclude>Hello World</div>',
link: function(scope) {
}
}
});
testApp.controller('testCtrl', function ($scope) {
$scope.user = "";
});
Here's JSFiddle: http://jsfiddle.net/2bKPj/
Now, all I need is for an input embedded in directive to be able to reflect user model directly in testCtrl controller.
I'm confused on how this beast works since I taught that scopes are shared in this case, no?
ngTransclude creates a new child scope which protorypically inherits from it's parent scope.
When you use a primitive on the child scope it shadows the parent scope's variable.
It's been already said thousand times: use the dot notation!
controller:
testApp.controller('testCtrl', function ($scope) {
$scope.data = { user : "Hello World" };
});
html:
<input type="text" ng-model="data.user"/><br />
Directive model:<span>{{ data.user }}</span>
Check my other answers for description:
bound element inside ngIf does not update binding
Directives inside ng-include

Resources