Ionic: [$injector:cdep] Circular dependency found - angularjs

Question

That error occur in a .factory function. In my project I have 2 .factory that both used each other. Below is my controller:
.controller('MyCtrl', function($scope, Factory_A) {
$scope.do = function(){
Factory_A.do_A();
};
})
Scenario 1:
.factory('Factory_A', function(Factory_B){
var value_A = 1;
return{
do_A: function(){
if(value_A == 1){
value_A++;
Factory_B.do_B();
}
else{
return "Success"
}
}
}
})
.factory('Factory_B', function(Factory_A){
var value_B = 0;
var do_B_1 = function(){
Factory_A.do_A();
};
return{
do_B: function(){
value_B++;
if(value_B > 0){
do_B_1();
}
return true;
}
}
});
Error: [$injector:cdep] Circular dependency found: Factory_A <- Factory_B <- Factory_A
Scenario 2:
.factory('Factory_A', function(){
var value_A = 1;
return{
do_A: function(){
if(value_A == 1){
value_A++;
Factory_B.do_B();
}
else{
return "Success"
}
}
}
})
.factory('Factory_B', function(Factory_A){
var value_B = 0;
var do_B_1 = function(){
Factory_A.do_A();
};
return{
do_B: function(){
value_B++;
if(value_B > 0){
do_B_1();
}
return true;
}
}
});
Error: Factory_B is not defined
Scenario 3:
.factory('Factory_A', function(Factory_B){
var value_A = 1;
return{
do_A: function(){
if(value_A == 1){
value_A++;
Factory_B.do_B();
}
else{
return "Success"
}
}
}
})
.factory('Factory_B', function(){
var value_B = 0;
var do_B_1 = function(){
Factory_A.do_A();
};
return{
do_B: function(){
value_B++;
if(value_B > 0){
do_B_1();
}
return true;
}
}
});
Error: Factory_A is not defined
Here is the demo for Scenario 3 shows how I simulate my project flow using a factory. Thanks.

Answer 1

use $injector to inject dependency runtime on self or circular dependency.
Full example code
Change you js in your demo page
angular.module('ionicApp', ['ionic'])
.controller('MyCtrl', function($scope, Factory_A) {
$scope.do = function(){
Factory_A.do_A();
};
})
.factory('Factory_A', function($injector){
var value_A = 1;
return{
do_A: function(){
if(value_A == 1){
value_A++;
var Factory_B = $injector.get('Factory_B');
Factory_B.do_B();
}
else{
return "Success"
}
}
}
})
.factory('Factory_B', function($injector){
var value_B = 0;
var do_B_1 = function(){
var Factory_A = $injector.get('Factory_A');
Factory_A.do_A();
};
return{
do_B: function(){
value_B++;
if(value_B > 0){
do_B_1();
}
return true;
}
}
});

Answer 2

I assume you're asking how to avoid the circular dependency.
In cases like these you might inject the $injector instead. And then when calling the methods inside each factory, you inject them at that time or cache them after the first use.
.factory( 'FactoryA', function($injector){
return {
funcFoo: function(){
var fb = $injecto.get('FactoryB')
fb.funcBar()
}
}
})
.factory( 'FactoryB', function($injector){
return {
funcFoo: function(){
var fa = $injecto.get('FactoryA')
fa.funcFoo()
}
}
})