xamarin.forms - Populating list view using a JSON subarray -

i have following json url. trying populate list view using subarrays hair[] , math[] after getting them json url.

here url http://pastebin.com/raw.php?i=2fzqlyxj

inside array "students" there subarray called "properties" , sub array inside "properties" called "grades". "hair" inside "properties" , "math" inside "grades".

here webservice class

public class webservice     {         public webservice ()         {          }          public async task<rootobject> getstudentinfoasync (string apiurl) {              var client = new httpclient ();               var response = await client.getstringasync(string.format(apiurl));              return jsonconvert.deserializeobject<rootobject>(response.tostring());          }     } 

and here view model

  public class property     {          public int iq { get; set; }         public string hair { get; set; }         public string glasses { get; set; }          public grade[] grades { get; set; }      }     public class studentinfo     {         public string name { get; set; }         public string lastname { get; set; }          public property[] properties { get; set; }          public string studentname {             get{ return string.format ("{0}", name); }         } //i accessing json sub arrays following "hair" , "math" properties.          public string[] haircolors     {                 {             return (properties ?? enumerable.empty<property>()).select(p => p.hair).toarray();         }     }        public string[] mathgrades     {                 {             return (properties ?? enumerable.empty<property>()).selectmany(p => p.grades ?? enumerable.empty<grade>()).select(g => g.math).toarray();         }     }      }      public class rootobject     {         public studentinfo[] students { get; set; }      } } 

and here how populate list view student names works. notice "studentname" not in subarray.

var sv = new webservice();             var es = await sv.getstudentinfoasync(apiurl);             xamarin.forms.device.begininvokeonmainthread( () => {                  listview.itemssource = es.students;             }); var cell = new datatemplate (typeof(textcell));              listview.itemtemplate = cell;             listview.itemtemplate.setbinding(textcell.textproperty, "studentname"); 

but need populate list view haircolors , mathgrades follows following code not work.

var sv = new webservice();             var es = await sv.getstudentinfoasync(apiurl);             xamarin.forms.device.begininvokeonmainthread( () => {                  listview.itemssource = es.students;             }); var cell = new datatemplate (typeof(textcell));              listview.itemtemplate = cell;             listview.itemtemplate.setbinding(textcell.textproperty, "haircolors");         listview.itemtemplate.setbinding (textcell.detailproperty, "mathgrades");    

what doesn't code work? how make work?

make custom converter this:

public class haircolorsconverter : ivalueconverter {     public object convert(object value, type targettype, object parameter, system.globalization.cultureinfo culture)     {         var haircolors = (string[])value;          return string.join(", ", haircolors);     }      public object convertback(object value, type targettype, object parameter, system.globalization.cultureinfo culture)     {         throw new notimplementedexception();     } } 

then bind like:

setbinding(textcell.textproperty, "haircolors", bindingmode.default, new haircolorsconverter());