Cant make this thing work.. pass data with stateParams please help

ionic-v1
21 
.state('pageProductDetails', {
     url: '/pageProductDetails/:item',
       templateUrl: 'templates/yourTemplate.html',
       params: { obj: null },
       controller: 'yourNewController'
     }
22

this is what i have now
.state(‘pageProductDetails’, {
url: ‘/pageProductDetails/:item’,
params: {obj: “null”},
templateUrl: ‘templates/pageProductDetails.html’,
controller: ‘pageProductDetailsCtrl’
})

i think i understnd the problem,

the different is the null where my null is with “”
and i cant change it because i use the ionic-creator and there is no accesses to this app.js file
i change if from the creator … (i can change it if i export the project folder but than i cant bring it back to the creator for keep working on it… )

you can see other solution to add to the param instead of { obj: null } ?
it looks like it always add the “” to the default value where i place the null from the creator