Illegal use of ngTransclude directive in the template

Question

I have two directive

app.directive('panel1', function ($compile) {     return {         restrict: "E",         transclude: 'element',         compile: function (element, attr, linker) {             return function (scope, element, attr) {                 var parent = element.parent();                 linker(scope, function (clone) {                     parent.prepend($compile( clone.children()[0])(scope));//cause error.                   //  parent.prepend(clone);// This line remove the error but i want to access the children in my real app.                 });             };         }     } });  app.directive('panel', function ($compile) {     return {         restrict: "E",         replace: true,         transclude: true,         template: "<div ng-transclude ></div>",         link: function (scope, elem, attrs) {         }     } }); 

And this is my view :

<panel1>     <panel>         <input type="text" ng-model="firstName" />     </panel> </panel1> 

Error: [ngTransclude:orphan] Illegal use of ngTransclude directive in the template! No parent directive that requires a transclusion found. Element: <div class="ng-scope" ng-transclude="">

I know that panel1 is not a practical directive. But in my real application I encounter this issue too.

I see some explanation on http://docs.angularjs.org/error/ngTransclude:orphan. But I don't know why I have this error here and how to resolve it.

EDIT I have created a jsfiddle page. Thank you in advance.

EDIT

In my real app panel1 does something like this:      <panel1>     <input type="text>     <input type="text> <!--other elements or directive-->     </panel1> 

result =>

    <div>     <div class="x"><input type="text></div>     <div class="x"><input type="text></div> <!--other elements or directive wrapped in div -->     </div> 

Answer 1

The reason is when the DOM is finished loading, angular will traverse though the DOM and transform all directives into its template before calling the compile and link function.

It means that when you call $compile(clone.children()[0])(scope), the clone.children()[0] which is your <panel> in this case is already transformed by angular. clone.children() already becomes:

<div ng-transclude="">fsafsafasdf</div>

(the panel element has been removed and replaced).

It's the same with you're compiling a normal div with ng-transclude. When you compile a normal div with ng-transclude, angular throws exception as it says in the docs:

This error often occurs when you have forgotten to set transclude: true in some directive definition, and then used ngTransclude in the directive's template.

DEMO (check console to see output)

Even when you set replace:false to retain your <panel>, sometimes you will see the transformed element like this:

<panel class="ng-scope"><div ng-transclude=""><div ng-transclude="" class="ng-scope"><div ng-transclude="" class="ng-scope">fsafsafasdf</div></div></div></panel>

which is also problematic because the ng-transclude is duplicated

DEMO

To avoid conflicting with angular compilation process, I recommend setting the inner html of <panel1> as template or templateUrl property

Your HTML:

<div data-ng-app="app">         <panel1>          </panel1>     </div> 

Your JS:

app.directive('panel1', function ($compile) {             return {                 restrict: "E",                 template:"<panel><input type='text' ng-model='firstName'>{{firstName}}</panel>",              }         }); 

As you can see, this code is cleaner as we don't need to deal with transcluding the element manually.

DEMO

Updated with a solution to add elements dynamically without using template or templateUrl:

app.directive('panel1', function ($compile) {             return {                 restrict: "E",                 template:"<div></div>",                 link : function(scope,element){                     var html = "<panel><input type='text' ng-model='firstName'>{{firstName}}</panel>";                     element.append(html);                     $compile(element.contents())(scope);                 }             }         }); 

DEMO

If you want to put it on html page, ensure do not compile it again:

DEMO

If you need to add a div per each children. Just use the out-of the box ng-transclude.

app.directive('panel1', function ($compile) {             return {                 restrict: "E",                 replace:true,                 transclude: true,                 template:"<div><div ng-transclude></div></div>" //you could adjust your template to add more nesting divs or remove              }         }); 

DEMO (you may need to adjust the template to your needs, remove div or add more divs)

Solution based on OP's updated question:

app.directive('panel1', function ($compile) {             return {                 restrict: "E",                 replace:true,                 transclude: true,                 template:"<div ng-transclude></div>",                 link: function (scope, elem, attrs) {                     elem.children().wrap("<div>"); //Don't need to use compile here.                    //Just wrap the children in a div, you could adjust this logic to add class to div depending on your children                 }             }         }); 

DEMO

Answer 2

You are doing a few things wrong in your code. I'll try to list them:

Firstly, since you are using angular 1.2.6 you should no longer use the transclude (your linker function) as a parameter to the compile function. This has been deprecated and should now be passed in as the 5th parameter to your link function:

compile: function (element, attr) {   return function (scope, element, attr, ctrl, linker) {   ....}; 

This is not causing the particular problem you are seeing, but it's a good practice to stop using the deprecated syntax.

The real problem is in how you apply your transclude function in the panel1 directive:

parent.prepend($compile(clone.children()[0])(scope)); 

Before I go into what's wrong let's quickly review how transclude works.

Whenever a directive uses transclusion, the transcluded content is removed from the dom. But it's compiled contents are acessible through a function passed in as the 5th parameter of your link function (commonly referred to as the transclude function).

The key is that the content is compiled. This means you should not call $compile on the dom passed in to your transclude.

Furthermore, when you are trying to insert your transcluded DOM you are going to the parent and trying to add it there. Typically directives should limit their dom manipulation to their own element and below, and not try to modify parent dom. This can greatly confuse angular which traverses the DOM in order and hierarchically.

Judging from what your are trying to do, the easier way to accomplish it is to use transclude: true instead of transclude: 'element'. Let's explain the difference:

transclude: 'element' will remove the element itself from the DOM and give you back the whole element back when you call the transclude function.

transclude: true will just remove the children of the element from the dom, and give you the children back when you call your transclude.

Since it seems you care only about the children, you should use transclude true (instead of getting the children() from your clone). Then you can simply replace the element with it's children (therefore not going up and messing with the parent dom).

Finally, it is not good practice to override the transcluded function's scope unless you have good reason to do so (generally transcluded content should keep it's original scope). So I would avoid passing in the scope when you call your linker().

Your final simplified directive should look something like:

   app.directive('panel1', function ($compile) {      return {        restrict: "E",        transclude: true,        link: function (scope, element, attr, ctrl, linker) {            linker(function (clone) {                element.replaceWith(clone);            });        }     }    }); 

Ignore what was said in the previous answer about replace: true and transclude: true. That is not how things work, and your panel directive is fine and should work as expected as long as you fix your panel1 directive.

Here is a js-fiddle of the corrections I made hopefully it works as you expect.

http://jsfiddle.net/77Spt/3/

EDIT:

It was asked if you can wrap the transcluded content in a div. The easiest way is to simply use a template like you do in your other directive (the id in the template is just so you can see it in the html, it serves no other purpose):

   app.directive('panel1', function ($compile) {        return {            restrict: "E",            transclude: true,            replace: true,            template: "<div id='wrappingDiv' ng-transclude></div>"                  }    }); 

Or if you want to use the transclude function (my personal preference):

   app.directive('panel1', function ($compile) {        return {            restrict: "E",            transclude: true,            replace: true,            template: "<div id='wrappingDiv'></div>",            link: function (scope, element, attr, ctrl, linker) {                linker(function (clone) {                    element.append(clone);                });            }        }    }); 

The reason I prefer this syntax is that ng-transclude is a simple and dumb directive that is easily confused. Although it's simple in this situation, manually adding the dom exactly where you want is the fail-safe way to do it.

Here's the fiddle for it:

http://jsfiddle.net/77Spt/6/