Row values with DataGrid SelectionChanged Event

[IvanDrago]

Hello, 

im new in Xamarin Forms. I tried to get the Row Values of a selected row in DataGrid. The Problem ist when i try this Knowledge Base Article it shows me null  in the selectedItem Breackpoint. Can someone help me to get this Values?

My MainPage.xaml.cs

using Newtonsoft.Json;
using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Data.SqlClient;
using System.Linq;
using System.Net;
using System.Net.Http;
using System.Text;
using System.Threading.Tasks;
using Telerik.XamarinForms.DataGrid.Commands;
using Xamarin.Forms;


namespace LagerApp.Portable
{
    public partial class MainPage : ContentPage
    {
        public MainPage()
        {
            InitializeComponent();
            GetArticles();
        }
        

        private void buttonbearbeiten_Clicked(object sender, EventArgs e)
        {
            
        }

        private void buttonNew_Clicked(object sender, EventArgs e)
        {
            popupNew.IsOpen = true;
            ArtNumber.Focus();
            ArtNumber.Text = "";
            WerkNumber.Text = "";
            Description.Text = "";
        }

        private void buttonDelete_Clicked(object sender, EventArgs e)
        {

        }

        private async void GetArticles()
        {
            HttpClientHandler clientHandler = new HttpClientHandler();
            clientHandler.ServerCertificateCustomValidationCallback = delegate { return true; };

            HttpClient client = new HttpClient(clientHandler);
            
            var response = await client.GetStringAsync("https://lagerapp.api.leonhardlang.at/api/Lager/GetArticle");
            var articles = JsonConvert.DeserializeObject<List<Articles>>(response);
            var columns = from c in articles select new { c.Artikelnummer, c.Werk, c.Kommentar };
            DataGrid.ItemsSource = columns;
        }

        private async void btnSave_Clicked(object sender, EventArgs e)
        {
            Articles articles = new Articles()
            {
                Artikelnummer = ArtNumber.Text,
                Werk = WerkNumber.Text,
                Kommentar = Description.Text
            };



            var json = JsonConvert.SerializeObject(articles);
            var content = new StringContent(json, Encoding.UTF8, "application/json");
            HttpClientHandler clientHandler = new HttpClientHandler();
            clientHandler.ServerCertificateCustomValidationCallback = delegate { return true; };


            HttpClient client = new HttpClient(clientHandler);
            
            var result = await client.PostAsync("https://lagerapp.api.leonhardlang.at/api/Lager/CreateArticle", content);

            if (result.StatusCode == HttpStatusCode.OK)
            {
                await DisplayAlert("Information","Erfolgreich angelegt", "Ok");
            }

            GetArticles();
            popupNew.IsOpen = false;
        }
       

        private void btnCancel_Clicked(object sender, EventArgs e)
        {
            popupNew.IsOpen = false;
        }

        private void DataGrid_SelectionChanged(object sender, Telerik.XamarinForms.DataGrid.DataGridSelectionChangedEventArgs e)
        {

            if (e.AddedItems.Count() > 0)
            {
                var selectedItem = e.AddedItems as Articles;

                
                Application.Current.MainPage.DisplayAlert("Info", $"{selectedItem.id}, " +
                    $"{selectedItem.Artikelnummer}, {selectedItem.Werk}, {selectedItem.Kommentar}", "OK");
            }

        }
    }

}

My Class: 

using System;
using System.Collections.Generic;
using System.Text;

namespace LagerApp.Portable
{
   
    public class Articles
    {
        public int id { get; set; }
        public string Artikelnummer { get; set; }
        public string Werk { get; set; }
        public string Kommentar { get; set; }
    }
}

 

Thank you

 

 

 

[Yana]

Hello Drago,

Inside the SelectionChanged event handler you can access the Selected item/items through the e.AddedItems collection.  The problem comes from the cast here:

var selectedItem = e.AddedItems as Articles;

e.AddedItems is a collection which holds a list of Articles objects, the cast is not correct, that's why selectedItem is null.  You would need to modify it like this:

var selectedItem = e.AddedItems.First() as Articles;

Please give it a try and let me know if you have any additional questions on this.

Regards,
Yana
Progress Telerik

[IvanDrago]

Omg. 

 

Thank you very much. That was the hint.

 

Cheers