Xamarin Android: Create Android App Contact Picker and Send SMS

Step 1: Open Visual Studio, New Project, Templates, Visual C#, Android, then Blank App (Android).

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

Step 2: Next go to Solution Explorer-> Project Name-> Components then Right Click to Get More Components then open new Dialog box. This dialog box to search the Xamarin.Mobile then Click Add App.

Step 3: Next to Open Solution Explorer, Project Name, Properties, AndroidManifest.xml Open the Xml page then give permission for READ_CONTACTS and SEND_SMS.

Step 4: Next to Open Solution Explorer, Project Name, Resources, layout, then Main.axml Click Open Design View and give the following code.

XML Code:

<?xml version="1.0" encoding="utf-8"?>

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="match_parent" android:layout_height="match_parent" android:id="@+id/lellayout" android:background="#3E4095">

    <RelativeLayout android:orientation="horizontal" android:layout_width="match_parent" android:id="@+id/linearLayout3" android:layout_height="wrap_content">

        <TextView android:text="TO" android:layout_width="wrap_content" android:layout_height="wrap_content" android:id="@+id/textView1" android:gravity="top" android:paddingTop="20dp" />

        <EditText android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_alignParentRight="true" android:id="@+id/txtmobilenum" android:layout_marginLeft="20dp" android:layout_marginRight="35dp" />

        <Button android:background="@drawable/addusergroup_48" android:layout_width="42.7dp" android:layout_alignParentRight="true" android:layout_height="wrap_content" android:id="@+id/btncontact" android:layout_marginLeft="20dp" android:layout_marginRight="2dp" />

    </RelativeLayout>

    <LinearLayout android:orientation="vertical" android:minWidth="25px" android:minHeight="25px" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_below="@id/linearLayout3" android:id="@+id/linearLayout6">

        <EditText android:inputType="textMultiLine" android:layout_width="match_parent" android:layout_height="wrap_content" android:id="@+id/txtbodymsg" />

    </LinearLayout>

    <LinearLayout android:orientation="vertical" android:minWidth="25px" android:minHeight="25px" android:layout_width="match_parent" android:layout_height="match_parent" android:layout_below="@id/linearLayout6" android:id="@+id/linearLayout7">

        <TableLayout android:orientation="horizontal" android:layout_width="match_parent" android:layout_below="@id/linearLayout3" android:stretchColumns="*" android:layout_height="wrap_content" android:id="@+id/linearLayout5">

            <TableRow android:minWidth="25px" android:minHeight="25px" android:layout_width="wrap_content" android:layout_height="match_parent" android:id="@+id/tableRow1">

                <Button android:text="Send" android:layout_width="wrap_content" android:layout_height="46.0dp" android:id="@+id/btnsmssend" android:layout_column="2" />

            </TableRow>

        </TableLayout>

    </LinearLayout>

</RelativeLayout>

Step 5: Next to Open Solution Explorer-> Project Name->MainActivity.cs.open c# Code Window. First give name space for using System.Linq;

Step 6: Next to declare Button and EditText Events and following to create Button Click Events.

C# Code:

using System;
using Android.App;
using Android.Content;
using Android.Runtime;
using Android.Views;
using Android.Widget;
using Android.OS;
using System.Linq;
namespace SMS
{
    [Activity(Label = "SMS", MainLauncher = true, Icon = "@drawable/icon")]
    public class MainActivity: Activity
    {
        Button btncontact;
        Button btnsmssend;
        EditText txtmobilenum;
        EditText txtbodymsg;
        protected override void OnCreate(Bundle bundle)
        {
            base.OnCreate(bundle);
            // Set our view from the "main" layout resource
            SetContentView(Resource.Layout.Main);
            txtbodymsg = FindViewById < EditText > (Resource.Id.txtbodymsg);
            txtmobilenum = FindViewById < EditText > (Resource.Id.txtmobilenum);
            btncontact = FindViewById < Button > (Resource.Id.btncontact);
            btnsmssend = FindViewById < Button > (Resource.Id.btnsmssend);
            btncontact.Click += Btncontact_Click;
            btnsmssend.Click += Btnsmssend_Click;
        }
    }
}

Step 7: Next to Pick the Contact Number in Contact List.so here create Contact Picker Button Click Event and then its passing Intent Value in OnActivityResult().

C# Code: 

private void Btncontact_Click(object sender, EventArgs e)
{
    var contactPickerIntent = new Intent(Intent.ActionPick,
        Android.Provider.ContactsContract.Contacts.ContentUri);
    StartActivityForResult(contactPickerIntent, 101);
}
protected override void OnActivityResult(int requestCode, Result resultCode, Intent data)
{
    if (requestCode == 101 && resultCode == Result.Ok)
    {
        //Ensure we have data returned
        if (data == null || data.Data == null)
            return;
        var addressBook = new Xamarin.Contacts.AddressBook(this);
        addressBook.PreferContactAggregation = false;
        //Load the contact via the android contact id
        // in the last segment of the Uri returned by the
        // android contact picker
        var contact = addressBook.Load(data.Data.LastPathSegment);
        //Use linq to find a mobile number
        var mobile = (from p in contact.Phones
            where
            p.Type == Xamarin.Contacts.PhoneType.Mobile
            select p.Number).FirstOrDefault();
        //See if the contact has a mobile number
        if (string.IsNullOrEmpty(mobile))
        {
            Toast.MakeText(this, "No Mobile Number for contact!",
                ToastLength.Short).Show();
            return;
        }
        txtmobilenum.Text = mobile;
    }
}

Step 8: Finally w Send the sms on given selected Number so here to create Send Button Event.

C# code:

private void Btnsmssend_Click(object sender, EventArgs e)
{
    try
    {
        if (string.IsNullOrWhiteSpace(txtbodymsg.Text))
        {
            Toast.MakeText(this, "SMS Text Body Is Empty", ToastLength.Long).Show();
        }
        else if (string.IsNullOrWhiteSpace(txtmobilenum.Text))
        {
            Toast.MakeText(this, "Enter Mobile Number", ToastLength.Long).Show();
        }
        else
        {
            Toast.MakeText(this, "Sending SMS... Please wait...", ToastLength.Short).Show();
            //Send SMS!
            var smsMgr = Android.Telephony.SmsManager.Default;
            smsMgr.SendTextMessage(txtmobilenum.Text, null, txtbodymsg.Text, null, null);
            Toast.MakeText(this, "SMS successfully sent", ToastLength.Short).Show();
            txtbodymsg.Text = "";
            txtmobilenum.Text = "";
        }
    }
    catch (Exception ex)
    {
        Toast.MakeText(this, ex.ToString(), ToastLength.Short).Show();
    }
}

Step 9: Press F5 or Build and Run the Application.