Q:
I have a controller that has a counter that changes from time to time.
That counter is tied to an attribute of a directive and read inside the link function of that directive.
How can I have a directive run a function each time that attr value changes?
A:
Inside your corresponding link function: (assuming your attribute is called counter and your scope variable is: scope)
scope.$watch(attrs.counter, function (newTime) {
//do something with the new Time
});Other way, surely more efficient way:
Interpolating the attribute
Inside your directive, set the scope property as following (it will be isolated so):
scope: { counter: '@'}The counter would automatically be observed providing the current value as long as the link function is called.
'@' better than '=' here since you I suppose you don't set the counter to a new value in your directive, meaning you just read it. Indeed, = is more useful for two-way data binding but you might not need it.
