angular - DoCheck in component do detect changes in a service -


i had problem of "how detect change in service, , make visible in component".

i solved using docheck() :

docheck(){     if( this.componentvar != this.myservice.servicevar){          this.componentvar = this.myservice.servicevar;     } }

and works well! didn't see anywhere method, question: think solution one?

$docheck considered way of "watching" replace $scope watch. can see code bind component service variable. close coupling , not recommended. runs @ every digest cycle causing performant issues. better way use 1 way binding on component variable. component become dump component more reusable.

var childcomponent = {   bindings: { componentvar: '<' },   controller: function () {     this.$onchanges = function (changes) {            if(changes.componentvar){                    //do here             }     };   } };  angular   .module('app')   .component('childcomponent', childcomponent);

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