how to use dependencies in path

Hi Community,

I want to have two comboBoxes, where one of them should change its content dependent on the choice of the first Combobox.
I tried aggregation binding and element Binding (I may have made mistakes) but I was not able to connect the data into my ComboBox.

My actual "workaround" shows Data with and hard coded Path:

Test.view.js:

var errorGroupComboBox = new sap.m.ComboBox({  placeholder: "{i18n>menu.captureSite.incidentTab.selectErrorGroup}",  items: {  path: "errorCodes>/ErrorCode", template: new sap.ui.core.Item({  key: "{errorCodes>group}",  text: "{errorCodes>groupDescription}"  })  },  selectedKey : "{input>/myErrorGroup}"  });  var errorGroupComboBoxLabel = new sap.m.Label({  text : "{i18n>menu.captureSite.incidentTab.errorGroupLabel}",  labelFor : errorGroupComboBox  });   incidentForm.addContent(errorGroupComboBoxLabel);  incidentForm.addContent(errorGroupComboBox);   var errorCodeComboBox = new sap.m.ComboBox({  placeholder: "{i18n>menu.captureSite.incidentTab.selectErrorCode}",  items:{  path: "errorCodes>/ErrorCode/0/error", template: new sap.ui.core.Item({  key: "{errorCodes>code}",  text: "{errorCodes>de_DE}"  })  },  selectedKey : "{input>/myErrors}"  });

The Controller got this code:

Test.controller.js:

onInit: function() {  jQuery.sap.require("sap.ui.model.json.JSONModel");  var input = {  date1   : new Date(),  date2   : new Date(new Date().getTime() + 1000*60*60*24*7),  date3   : new Date(),  myDrink : "",  myMachine: "",  myErrorGroup: "",  myErrors: "",  takeAway : ""  };  var model = new sap.ui.model.json.JSONModel(input);  sap.ui.getCore().setModel(model, "input");  this.getView().setModel(model, "input");  // this.getView().setModel(new sap.ui.model.json.JSONModel(input), "input");  this.getView().setModel(new sap.ui.model.json.JSONModel("model/coffee.json"), "coffee");  this.getView().setModel(new sap.ui.model.json.JSONModel("model/equipments.json"), "equipments");  this.getView().setModel(new sap.ui.model.json.JSONModel("model/errorCodes.json"), "errorCodes");      this.bus = sap.ui.getCore().getEventBus();
}

My Example Data looks like this:

errorCodes.json:

{
"ErrorCode" : [                      {                           "group" : 10,                           "groupDescription" : "Example Group Alpha" ,                           "active" : true,                           "error" : [                                          {"code" : 100 , "de_DE" : "TestDaten 1", "en_EN": "test data 1" , "active" : true},                                          {"code" : 101 , "de_DE" : "TestDaten 2", "en_EN": "test data 2" , "active" : true},                                          {"code" : 102 , "de_DE" : "TestDaten 3", "en_EN": "test data 3", "active" : true }                           ]                      },                      {                           "group" : 11,                           "groupDescription" : "Example Groupe Beta" ,                           "active" : true,                           "error" : [                                          {"code" : 110 , "de_DE" : "DatenTest 4", "en_EN": "Data test 4" , "active" : true},                                          {"code" : 111 , "de_DE" : "DatenTest 5", "en_EN": "Data test 5" , "active" : true},                                          {"code" : 112 , "de_DE" : "DatenTest 6", "en_EN": "Data test 6", "active" : true }                           ]                 }                 ]
}

My goal is to chose a "group" in the first combobox and then chose an "error" from this "group" in the second comboBox.

I hope you can give me some tips, links or even examples to help me with this issue.

Regards,
Dain