Transclude share scope with directive template - angularjs

Assume this directive:
<validation-errors field="someField">Some errors: {{errors}}</validation-errors>
I thought I could create the directive function simple as this:
return {
require: '^form',
restrict: 'E',
link: link,
scope: {
field: '#'
},
transclude: true,
template: '<span ng-show="errors" class="alert-danger" ng-transclude></span>'
};
function link(scope, el, attr, ctrl, transcludeFn) {
scope.errors = ctrl.Validator.getErrors(attr.field);
}
But since Transclusion is the process of extracting a collection of DOM element from one part of the DOM and copying them to another part of the DOM, while maintaining their connection to the original AngularJS scope from where they were taken. (from docs), the scope doesn't work like I thought it would.
So I tried this which works, except that the "Some errors" part is duplicated:
transcludeFn(function(clone, transScope) {
scope.errors = transScope.errors = ctrl.Validator.getErrors(attr.field);
el.append(clone);
});
It doesn't work if I remove el.append(clone);.
What's the best way to make the transcluded content share the directive template's scope?

If you want to create the errors using the directive, give something like this a try, I've updated the code so that it compiles the template as well, now working exactly as the ng-transclude directive would out of the box.
'use strict';
/* Directives */
angular.module('myApp.directives', []).
directive('errordirective', ['$compile',function($compile) {
return {
restrict: 'E',
scope: {
field: '#',
},
transclude: true,
//Create some error text
controller: function() {
this.errorText = "Some Errors We Created";
//Make the template available to the link fn, and make it an angular element.
this.template = angular.element('<span class="alert-danger" ng-transclude></span>')
},
//Make the controller available easily
controllerAs: 'Errors',
//Bind the scope properties to the controller, only works with controllerAs
bindToController: true,
template: '<span class="alert-danger" ng-transclude></span>',
link: function(scope, elem, attrs, ctrl, transcludefn) {
//Replace the original element with the new one that has the error text from our controller
transcludefn(scope, function(el) {
var template = ctrl.template;
var html = el.html();
//Add the transcluded content to the template
template.html(html);
//Compile the template with the appropriate scope
template = $compile(template)(scope);
//Replace with the new template
elem.replaceWith(template);
});
}
};
}]);

Related

ng-repeat inside a directive template - access index

I have the following problem:
I have a custom directive, which shows one or more tables, by using ng-repeat inside the template string. Inside each table, several other custom directives are placed. I want these to know the index of the element used, but cant manage to get this done. My code looks like this now:
.directive('myStuffText', function ($rootScope){
return {
restrict: 'A',
require: '^form',
replace: true,
scope: true,
template:
......
'<table border="1" ng-repeat="elt in myModel.newStuffList">
......
'<tr>' +
'<td colspan="3"><div my-add-some-editor my-element-index="$index"/></td>' +
'</tr>'
'</table>',
link: function (scope, elt, attrs){
scope.cockpitPolicyModel.newPolicyList = [];
}
};
})
Independently from how I try, I always get the string $index or {{$index}} in the template function of the my-add-some-editor directive, not the value of it..
Edit - added the nested directive:
.directive('myAddSomeEditor', function($rootScope){
return {
restrict: 'A',
require: '^form',
scope: true,
template: function ($scope, $attr){
return
.....
'<span id="myAddSomeEditor" name="myAddSomeEditor" class="form-control" my-generic-editor '+
'my-input-mapping="myModel.someText"></span>'
.....
;
}
};
})
That probably happens because in your my-add-some-editor directive you have this definition in the isolate scope:
myElementIndex: '#'
That's why you're getting the literal string of what you're writing there in the HTML.
Change that to:
myElementIndex: '='
EDIT: Since you said you're not using isolated scope, try this in the parent directive: try doing my-element-index="{{$index}}". And this in the child directive's link function:
link: function (scope, elem, attr) {
attr.$observe('index', function(val) {
scope.index = val;
});
}

How to bind content of tag into into directive's scope?

Say I have a directive like such:
<my-directive>This is my entry!</my-directive>
How can I bind the content of the element into my directive's scope?
myApp.directive('myDirective', function () {
return {
scope : {
entry : "" //what goes here to bind "This is my entry" to scope.entry?
},
restrict: "E",
template: "<textarea>{{entry}}</textarea>"
link: function (scope, elm, attr) {
}
};
});
I think there's much simpler solution to the ones already given. As far as I understand, you want to bind contents of an element to scope during initialization of directive.
Given this html:
<textarea bind-content ng-model="entry">This is my entry!</textarea>
Define bind-content as follows:
directive('bindContent', function() {
return {
require: 'ngModel',
link: function ($scope, $element, $attrs, ngModelCtrl) {
ngModelCtrl.$setViewValue($element.text());
}
}
})
Here's a demo.
I may have found a solution. It relies on the transclude function of directives. It works, but I need to better understand transclusion before being sure this is the right way.
myApp.directive('myDirective', function() {
return {
scope: {
},
restrict: 'E',
replace: false,
template: '<form>' +
'<textarea ng-model="entry"></textarea>' +
'<button ng-click="submit()">Submit</button>' +
'</form>',
transclude : true,
compile : function(element,attr,transclude){
return function (scope, iElement, iAttrs) {
transclude(scope, function(originalElement){
scope.entry = originalElement.text(); // this is where you have reference to the original element.
});
scope.submit = function(){
console.log('update entry');
}
}
}
};
});
You will want to add a template config to your directive.
myApp.directive('myDirective', function () {
return {
scope : {
entry : "=" //what goes here to bind "This is my entry" to scope.entry?
},
template: "<div>{{ entry }}</div>", //**YOU DIDN'T HAVE A TEMPLATE**
restrict: "E",
link: function (scope, elm, attr) {
//You don't need to do anything here yet
}
};
});
myApp.controller('fooController', function($scope){
$scope.foo = "BLAH BLAH BLAH!";
});
And then use your directive like this:
<div ng-controller="fooController">
<!-- sets directive "entry" to "foo" from parent scope-->
<my-directive entry="foo"></my-directive>
</div>
And angular will turn that into:
<div>THIS IS MY ENTRY</div>
Assuming that you have angular setup correctly and are including this JS file onto your page.
EDIT
It sounds like you want to do something like the following:
<my-directive="foo"></my-directive>
This isn't possible with ELEMENT directives. It is, however, with attribute directives. Check the following.
myApp.directive('myDirective', function () {
return {
template: "<div>{{ entry }}</div>", //**YOU DIDN'T HAVE A TEMPLATE**
restrict: "A",
scope : {
entry : "=myDirective" //what goes here to bind "This is my entry" to scope.entry?
},
link: function (scope, elm, attr) {
//You don't need to do anything here yet
}
};
});
Then use it like this:
<div my-directive="foo"></div>
This will alias the value passed to my-directive onto a scope variable called entry. Unfortunately, there is no way to do this with an element-restricted directive. What is preventing it from happening isn't Angular, it is the html5 guidelines that make what you are wanting to do impossible. You will have to use an attribute directive instead of an element directive.

AngularJS How to access elements inside directive before they get replaced

How do I get the input element from within the directive before the template overwrites the contents?
html
<div xxx>
<input a="1" />
</div>
js
app.directive('xxx', function(){
return {
restrict: 'A',
template: '<p></p>',
replace: true, //if false, just leaves the parent div, still no input
compile: function(element, attrs) {
console.log(element);
return function (scope, iElement, iAttrs) {
}
}
};
});
i am on angular 1.0.x, I cannot pass in optional scope parameters with the '=?' syntax and i want to be able to override a portion of the default template of the directive in a very flexible way. instead of adding a scope variable or attribute everytime that I just plan on passing through the directive, I want to be able to supply the whole element to be used.
edit
the input must retain the scope of the directive, and not the parent.
edit
I am trying to include a partial template inside a directive that will overwrite a piece of the actual template. The piece I am including therefore needs to have access to the directive's scope and not the parent's.
Update
It seems if I do not provide a template or a template URL and instead replace the contents manually using the $templateCache I can have access to the inner elements. I want to let angular handle the template and the replacement though and just want to be able to access the contents in the directive naturally before they get replaced.
Solution
Plunkr
html
<body ng-controller="MainCtrl">
<div editable="obj.email">
<input validate-email="error message" ng-model="obj.email" name="contactEmail" type="text" />
</div>
</body>
js
app.controller('MainCtrl', function($scope) {
$scope.obj = {
email: 'xxx'
};
});
app.directive('editable', function($log){
return {
restrict: 'A',
transclude: true,
template: '<div ng-show="localScopeVar">{{value}}<div ng-transclude></div></div>',
scope: {
value: '=editable'
},
link: function(scope) {
scope.localScopeVar = true;
}
};
});
app.directive('validateEmail', function($log){
return {
restrict: 'A',
require: 'ngModel',
scope: true,
link: function(scope, el, attrs, ctrl) {
console.log(attrs['validateEmail']);
}
};
});
I believe you're looking for the transclude function (link is to 1.0.8 docs). You can see what's going on with:
app.directive('xxx', function($log){
return {
restrict: 'A',
transclude: true,
compile: function(element, attrs, transclude) {
$log.info("every instance element:", element);
return function (scope, iElement, iAttrs) {
$log.info("this instance element:", element);
transclude(scope, function(clone){
$log.info("clone:", clone);
});
}
}
};
});

Access Parent Scope in Transcluded Directive

I would like to access a parent directive's scope, but I can't seem to get the right combination of settings. Is this possible and is it the right approach?
I really want to avoid putting something like SOME_CONST (which would help me make DOM updates through control flow) in MyCtrl
<div ng-controller="MyCtrl">
<parent>
<child></child>
</parent>
</div>
var myApp = angular.module('myApp',[]);
function MyCtrl($scope) {
$scope.obj = {prop:'foo'};
}
myApp.directive('parent', function() {
return {
scope: true,
transclude: true,
restrict: 'EA',
template: '<div ng-transclude><h1>I\'m parent {{obj.prop}}<h1></div>',
link: function(scope, elem, attrs) {
scope.SOME_CONST = 'someConst';
}
}
});
myApp.directive('child', function() {
return {
restrict: 'EA',
template: '<h1>I\'m child.... I want to access my parent\'s stuff, but I can\'t. I can access MyCtrlScope though, see <b>{{obj.prop}}</b></h1> how can I access the <b>SOME_CONST</b> value in my parent\'s link function? is this even a good idea? {{SOME_CONST}}. I really don\'t want to put everything inside the MyCtrl',
}
});
Please see this fiddle
Thanks
With transclude: true and scope: true, the parent directive creates two new scopes:
Scope 004 is a result of scope: true, and scope 005 is a result of transclude: true. Since the child directive does not create a new scope, it uses transcluded scope 005. As you can see from the diagram there is no path from scope 005 to scope 004 (except via private property $$prevSibling, which goes in the opposite direction of $$nextSibling -- but don't use those.)
#joakimbl's solution is probably best here, although I think it is more common to define an API on the parent directive's controller, rather than defining properties on this:
controller: function($scope) {
$scope.SOME_CONST = 'someConst';
this.getConst = function() {
return $scope.SOME_CONST;
}
}
Then in the child directive:
link:function(scope,element,attrs,parentCtrl){
scope.SOME_CONST = parentCtrl.getConst();
},
This is how the tabs and pane directives work on Angular's home page ("Create Components" example).
Normally the way you access a parent scope variable in a directive is through bi-directional binding (scope:{model:'=model'} - see the angular guide on directives) in the directive configuration), but since you're using transclusion this is not so straight forward. If the child directive will always be a child of the parent directive you can however configure it to require the parent, and then get access to the parent controller in the child link function:
myApp.directive('parent', function() {
return {
scope: true,
transclude: true,
restrict: 'EA',
template: '<div ng-transclude><h1>I\'m parent {{obj.prop}}<h1></div>',
controller: function($scope) {
$scope.SOME_CONST = 'someConst';
this.SOME_CONST = $scope.SOME_CONST;
}
}
});
myApp.directive('child', function() {
return {
restrict: 'EA',
require:'^parent',
scope:true,
link:function(scope,element,attrs,parentCtrl){
scope.SOME_CONST = parentCtrl.SOME_CONST;
},
template: '<h1>I\'m child.... I want to access my parent\'s stuff, but I can\'t. I can access MyCtrlScope though, see <b>{{obj.prop}}</b></h1> how can I access the <b>SOME_CONST</b> value in my parent\'s link function? is this even a good idea? {{SOME_CONST}}. I really don\'t want to put everything inside the MyCtrl',
}
});
See this update: http://jsfiddle.net/uN2uv/
I just had the same problem and finally solved it with the angular manual ;)
In short: you need to use a controller in your parent directive and require that controller in your child directive. This way you are able to get your parent properties.
See https://docs.angularjs.org/guide/directive
Chapter: Creating Directives that Communicate
I changed your fiddle to use a controller, now you can access your constant:
https://jsfiddle.net/bbrqdmt3/1/
var myApp = angular.module('myApp',[]);
function MyCtrl($scope) {
$scope.obj = {prop:'foo'};
}
myApp.directive('parent', function() {
return {
scope: true,
transclude: true,
restrict: 'EA',
template: '<div ng-transclude><h1>I\'m parent {{obj.prop}}<h1></div>',
controller: function($scope) {
this.getConst= function() {
return 'someConst';
}
},
}
});
myApp.directive('child', function() {
return {
restrict: 'EA',
require : '^parent',
link: function(scope, element, attrs, ctrl) {
scope.value= ctrl.getConst();
},
template: '<h1>I\'m child.... I want to access my parent\'s stuff, but I can\'t. I can access MyCtrlScope though, see <b>{{obj.prop}}</b></h1> how can I access the <b>SOME_CONST</b> value in my parent\'s link function? is this even a good idea? {{value}}. I really don\'t want to put everything inside the MyCtrl',
}
});
There's a transclude fn in the arguments of the link fn after the controller.
myApp.directive('parent', function() {
return {
scope: true,
transclude: true,
restrict: 'EA',
template: '<div><h1>I'm a parent header.</h1></div>',
link: function (scope, el, attrs, ctrl, transclude) {
transclude(scope, function (clone, scope) {
element.append(clone); // <-- will transclude it's own scope
});
},
controller: function($scope) {
$scope.parent = {
binding: 'I\'m a parent binding'
};
}
}
});
myApp.directive('child', function() {
return {
restrict: 'EA',
require:'^parent',
scope:true,
link:function(scope,element,attrs,parentCtrl){
},
template: '<div>{{parent.binding}}</div>' // <-- has access to parent's scope
}
});

How to hide element if transcluded contents are empty?

I created a very simple directive which displays a key/value pair. I would like to be able to automatically hide the element if the transcluded content is empty (either zero length or just whitespace).
I cannot figure out how to access the content that gets transcluded from within a directive.
app.directive('pair', function($compile) {
return {
replace: true,
restrict: 'E',
scope: {
label: '#'
},
transclude: true,
template: "<div><span>{{label}}</span><span ng-transclude></span></div>"
}
});
For example, I would like the following element to be displayed.
<pair label="My Label">Hi there</pair>
But the next two elements should be hidden because they don't contain any text content.
<pair label="My Label"></pair>
<pair label="My Label"><i></i></pair>
I am new to Angular so there may be a great way handle this sort of thing out of the box. Any help is appreciated.
Here's an approach using ng-show on the template and within compile transcludeFn checking if transcluded html has text length.
If no text length ng-show is set to hide
app.directive('pair', function($timeout) {
return {
replace: true,
restrict: 'E',
scope: {
label: '#'
},
transclude: true,
template: "<div ng-show='1'><span>{{label}} </span><span ng-transclude></span></div>",
compile: function(elem, attrs, transcludeFn) {
transcludeFn(elem, function(clone) {
/* clone is element containing html that will be transcludded*/
var show=clone.text().length?'1':'0'
attrs.ngShow=show;
});
}
}
});
Plunker demo
Maybe a bit late but you can also consider using the CSS Pseudo class :empty.
So, this will work (IE9+)
.trancluded-item:empty {
display: none;
}
The element will still be registered in the dom but will be empty and invisible.
The previously provided answers were helpful but didn't solve my situation perfectly, so I came up with a different solution by creating a separate directive.
Create an attribute-based directive (i.e. restrict: 'A') that simply checks to see if there is any text on all the element's child nodes.
function hideEmpty() {
return {
restrict: 'A',
link: function (scope, element, attr) {
let hasText = false;
// Only checks 1 level deep; can be optimized
element.children().forEach((child) => {
hasText = hasText || !!child.text().trim().length;
});
if (!hasText) {
element.attr('style', 'display: none;');
}
}
};
}
angular
.module('directives.hideEmpty', [])
.directive('hideEmpty', hideEmpty);
If you only want to check the main element:
link: function (scope, element, attr) {
if (!element.text().trim().length) {
element.attr('style', 'display: none;');
}
}
To solve my problem, all I needed was to check if there were any child nodes:
link: function (scope, element, attr) {
if (!element.children().length) {
element.attr('style', 'display: none;');
}
}
YMMV
If you don't want to use ng-show every time, you can create a directive to do it automatically:
.directive('hideEmpty', ['$timeout', function($timeout) {
return {
restrict: 'A',
link: {
post: function (scope, elem, attrs) {
$timeout(function() {
if (!elem.html().trim().length) {
elem.hide();
}
});
}
}
};
}]);
Then you can apply it on any element. In your case it would be:
<span hide-empty>{{label}}</span>
I am not terribly familiar with transclude so not sure if it helps or not.
but one way to check for empty contents inside the directive code is to use iElement.text() or iElement.context object and then hide it.
I did it like this, using controllerAs.
/* inside directive */
controllerAs: "my",
controller: function ($scope, $element, $attrs, $transclude) {
//whatever controller does
},
compile: function(elem, attrs, transcludeFn) {
var self = this;
transcludeFn(elem, function(clone) {
/* clone is element containing html that will be transcluded*/
var showTransclude = clone.text().trim().length ? true : false;
/* I set a property on my controller's prototype indicating whether or not to show the div that is ng-transclude in my template */
self.controller.prototype.showTransclude = showTransclude;
});
}
/* inside template */
<div ng-if="my.showTransclude" ng-transclude class="tilegroup-header-trans"></div>

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