Stuck creating a custom css style directive - angularjs

Question

For an only visual editor I'm trying to create a new directive that writes a CSS style. I'm stuck at trying to get the directive to update when a checkbox is clicked to make the background-color property transparent.
Here's my (non-working) directive:
myApp.directive('customstyle', function () {
return {
restrict: 'E',
link: function (scope, element, attrs) {
var bgColor;
scope.$watch(attrs.myTransparent, function (value) {
if (value) {
bgColor = 'transparent';
} else {
bgColor = attrs.myBgcolor;
}
updateStyle();
}, true);
function updateStyle() {
var htmlText = '<style>.' + attrs.myClass + '{';
htmlText += 'background-color: ' + bgColor + ';';
htmlText += "}</style>";
element.replaceWith(htmlText);
}
updateStyle();
}
}
});
and html element:
<customstyle my-class="examplediv" my-transparent="settings.Window.Transparent" my-bgcolor="settings.Window.BackgroundColor"></customstyle>
Here's a jsfiddle of the situation: http://jsfiddle.net/psinke/jYQc6/
Any help would be greatly appreciated.

Answer 1

Try using the directive directly on the element you want to change, it's easier to do and to maintain.
HTML:
<div class="examplediv customstyle"
my-transparent="settings.Window.Transparent"
my-bgcolor="{{settings.Window.BackgroundColor}}">
</div>
Note: Use {{settings.Window.BackgroundColor}} to pass the property's value and not a String.
Directive:
myApp.directive('customstyle', function () {
return {
restrict: 'AC',
link: function (scope, element, attrs) {
scope.$watch(attrs.myTransparent, function (value) {
element.css('background-color', (value ? 'transparent' : attrs.myBgcolor));
});
}
}
});
Note: Use element.css() to change CSS properties directly on the element.
jsFiddler: http://jsfiddle.net/jYQc6/8/

Answer 2

I was having the same problem and using bmleite's solution solved it. I had a custom element with a custom attribute very similar to the one above, and changing the directive to be applied on a regular DIV instead of the custom attribute fixed it for me.
In my solution I also have the following line of code right after the element has been modified:
$compile(element.contents())(scope);
Remember to inject the $compile service in the directive function declaration:
myApp.directive('directiveName', function ($compile) { ...
Thanks for a great post!