How to send and retrieve parameters using $state.go toParams and $stateParams?

I am using AngularJS v1.2.0-rc.2 with ui-router v0.2.0. I want to pass the referrer state to another state so I use the toParams of $state.go like so:

$state.go('toState', {referer: $state.current.name});

According to the docs, this should populate the $stateParams on the toState controller, but it is undefined. What am I missing?

I've created a plunk to demonstrate:

http://plnkr.co/edit/ywEcG1

If you want to pass non-URL state, then you must not use url when setting up your state. I found the answer on a PR and did some monkeying around to better understand.

$stateProvider.state('toState', {
  templateUrl:'wokka.html',
  controller:'stateController',
  params: {
    'referer': 'some default', 
    'param2': 'some default', 
    'etc': 'some default'
  }
});

Then you can navigate to it like so:

$state.go('toState', { 'referer':'jimbob', 'param2':37, 'etc':'bluebell' });

Or:

var result = { referer:'jimbob', param2:37, etc:'bluebell' };
$state.go('toState', result);

And in HTML thusly:

<a ui-sref="toState(thingy)" class="list-group-item" ng-repeat="thingy in thingies">{{ thingy.referer }}</a>

This use case is completely uncovered in the documentation, but I think it's a powerful means on transitioning state without using URLs.

The Nathan Matthews's solution did not work for me but it is totally correct but there is little point to reaching a workaround:

The key point is: Type of defined parameters and toParamas of $state.go should be same array or object on both sides of state transition.

For example when you define a params in a state as follows you means params is array because of using "[]":

$stateProvider
.state('home', {
    templateUrl: 'home',
    controller:  'homeController'
})
.state('view', {
    templateUrl: 'overview',
    params:      ['index', 'anotherKey'],
    controller:  'overviewController'
})

So also you should pass toParams as array like this:

params = { 'index': 123, 'anotherKey': 'This is a test' }
paramsArr = (val for key, val of params)
$state.go('view', paramsArr)

And you can access them via $stateParams as array like this:

app.controller('overviewController', function($scope, $stateParams) {
    var index = $stateParams[0];
    var anotherKey = $stateParams[1];
});

Better solution is using object instead of array in both sides:

$stateProvider
.state('home', {
    templateUrl: 'home',
    controller:  'homeController'
})
.state('view', {
    templateUrl: 'overview',
    params:      {'index': null, 'anotherKey': null},
    controller:  'overviewController'
})

I replaced [] with {} in params definition. For passing toParams to $state.go also you should using object instead of array:

$state.go('view', { 'index': 123, 'anotherKey': 'This is a test' })

then you can access them via $stateParams easily:

app.controller('overviewController', function($scope, $stateParams) {
    var index = $stateParams.index;
    var anotherKey = $stateParams.anotherKey;
});

All I had to do was add a parameter to the url state definition like so

url: '/toState?referer'

Doh!