Xamarin.Android - List View Using SQL Server Database

Let’s start,

Prior to starting an Android Application, we need to Create SQL server Database Using WEB API. Refer to this one,

• Xamarin Android: Create Login with WEB API Using Azure SQL Server - Part One

Step 1

Open Visual Studio->New Project->Templates->Visual C#->Android->Blank App

Select Blank App. Then give Project Name and Project Location.

Step 2

Go to Solution Explorer-> Project Name-> References then Right Click to Manage Nuget Packages then open new Dialog box. This dialog box to search the Json then Install theNewtonsoft.Json Packages.

Step 3

Next to Open Solution Explorer-> Project Name->Resources->layout->Main.axmlClick Open Design View.

Step 4

Then Go to Toolbar Select ListViewDrag and Drop in Design Page then give android:id="@+id/ListView".

XMLCode 

<?xmlversion="1.0"encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
   android:orientation="vertical"
   android:layout_width="match_parent"
   android:layout_height="match_parent"
   android:minWidth="25px"
   android:minHeight="25px">
    <ListView
      android:minWidth="25px"
      android:minHeight="25px"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      android:id="@+id/Listview" />
</LinearLayout>

Step 5

Next to create New Layout for List View Design Adapter Page, go to Solution Explorer-> Project Name->Resources->layout then Right Click to Add->New Item then open new Dialog box. Then select Android Layout then give name for ListViewDesign.axml

Step 6

Then open Solution Explorer-> Project Name->Resources->Layout->ListViewDesign.axml click to open Design View then give the  following code, here we create two textviews, one for Name ,another one for Contact Number.

XML Code 

<?xmlversion="1.0"encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
   android:orientation="vertical"
   android:layout_width="match_parent"
   android:layout_height="match_parent">
    <TextView
      android:text="Name"
      android:textAppearance="?android:attr/textAppearanceLarge"
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:id="@+id/TxtName" />
    <TextView
      android:textAppearance="?android:attr/textAppearanceLarge"
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:id="@+id/TxtNumber"
      android:text="Number" />
</LinearLayout>

Step 7

We need to assign the SQL List Values in any Class so here create new class. Go to Solution Explorer-> Project Name then Right Click to Add->New Item then open new Dialog box. Then select class File give name for UserInfo.cs

Step 8

Then open UserInfo.cs give following code. 

public class UserInfo {
    publicstring firstname {
        get;
        set;
    }
    publicstring contact_no {
        get;
        set;
    }
}

Step 9

Afterwardsto open Solution Explorer-> Project Name->MainActivity.cs then Add below Namespaces. 

using System.Collections.Generic;
using Newtonsoft.Json;
using System.Net.Http.Headers;
using System.Net.Http;

Step 10

Next to Open Solution Explorer-> Project Name->MainAtivity.cs,Open Oncreate()then implement following code

C# Code 

public static Context context;
public static List < UserInfo > UserInfoList = newList < UserInfo > ();
public static ListView ListView;
protected override void OnCreate(Bundle bundle) {
    base.OnCreate(bundle);
    SetContentView(Resource.Layout.Main);
    ListView = FindViewById < ListView > (Resource.Id.Listview);
    GetList list = newGetList();
    list.Execute();
}

Step 11

Below Oncreate() declare the AsyncTask for SQL Server Data Retrieve. Here only we call and assign the values for Base Adapter .

C# Code 

public class GetList: AsyncTask {
    Context con;
    protected override Java.Lang.Object DoInBackground(params Java.Lang.Object[] @params) {
        System.Net.Http.HttpClient client = new System.Net.Http.HttpClient();
        var _WebApiUrl = string.Format("https://URL/api/Account/Profile");
        client.DefaultRequestHeaders.Accept.Add(newMediaTypeWithQualityHeaderValue("application/json"));
        HttpResponseMessage messge = client.GetAsync(_WebApiUrl).Result;
        var Return_EventList = messge.Content.ReadAsStringAsync().Result;
        var EventList = JsonConvert.DeserializeObject < List < UserInfo >> (Return_EventList);
        foreach(var data in EventList) {
            UserInfoList.Add(data);
        }
        return true;
    }
    protected override void OnPreExecute() {
        base.OnPreExecute();
    }
    protected override void OnPostExecute(Java.Lang.Object result) {
        base.OnPostExecute(result);
        ListView.Adapter = newUserInfoListAdapter(context, UserInfoList);
    }
}

Step 12

Next to create new BaseAdapter class. Declare all variables of ListViewDesign.axml here

C# Code 

class UserInfoListAdapter: BaseAdapter < UserInfo > {
    private List < UserInfo > mItem = newList < UserInfo > ();
    private Context context;
    public UserInfoListAdapter(Context mcontext, List < UserInfo > mItems) {
        mItem.Clear();
        mItem = mItems;
        context = mcontext;
        this.NotifyDataSetChanged();
    }
    public override UserInfothis[int position] {
        get {
            return mItem[position];
        }
    }
    public override int Count {
        get {
            return mItem.Count;
        }
    }
    public Context MContext {
        get;
        privateset;
    }
    public override long GetItemId(int position) {
        return position;
    }
    public override View GetView(int position, View convertView, ViewGroup parent) {
        View listitem = convertView;
        listitem = LayoutInflater.From(parent.Context).Inflate(Resource.Layout.ListViewDesign, parent, false);
        TextView TxtName = listitem.FindViewById < TextView > (Resource.Id.TxtName);
        TextView TxtNumber = listitem.FindViewById < TextView > (Resource.Id.TxtNumber);
        TxtName.Text = mItem[position].firstname;
        TxtNumber.Text = mItem[position].contact_no;
        listitem.Click += (object sender, EventArgs e) => {
            Toast.MakeText(parent.Context, "Clicked " + mItem[position].firstname, ToastLength.Long).Show();
        };
        return listitem;
    }
}

Step 13

Press F5 or Build and Run the Application

Finally, you have successfully created a Xamarin Android List View using SQL Server.