Manipulating the DOM with link

Step 1: Declare Link Function

function MyDirective(){
    var ddo = {
        scope: {...},
        link: linkFunction,
        ...
        templateUrl: 'template.html'
    };
    return ddo;
}

Step 2: Define the Link Function

function LinkFunction(scope, element, attrs, controller){
    ...
}

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Summary

• DOM manipulation usually done inside of the link function declared on the DDO.
• Link function does not support injection. To use injected components, services, inject them into directive.
• 'scope' parameter is the exact $scope in directive's controller.
• 'element' object represents the element of the directive:
  • Top level element.
  • It's jqLite object or jQuery object (if jQuery is included before Angular).

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Using Directive’s transclude to Wrap Other Elements

Step 1: Set transclude to true

function MyDirective(){
    var ddo = {
        scope: {...},
        transclude: true,
        ...
        templateUrl: "template.html"
    };
    return ddo;
}

Step 2: Wrap Some Parent Content

<my-directive>
    <span>
        WARNING! WARNING! {{ctrl.someProp}}
    </span>
</my-directive>

{{ctrl.someProp}} - evaluated in the parent controller, NOT in our directive

Step 3: ng-transclude To Place Wrapper Content

<div>
    ...
    <div ng-transclude></div>
</div>

<div ng-transclude></div> - insert evaluated wrapped content into element marked with ng-transclude

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Summary

• transclude allows whole templates to be passed into a directive.
• The wrapped content is evaluated in the parent's context, NOT in the directive's context.
• In the DDO:
  • transclude: true
• In directive's template:
  • ng-transclude attribute designates place for evaluated wrapped content.

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