如何通过按钮发送直接短信

Question

My end goal is to create an application that will send a text message to a database of phone numbers that the user inputs. Then, by pressing a button they can automatically respond to all people that they are driving, and would like them to text them back another time. The automatic message response is also customizable. I'm using Xamarin for Visual Studios, and am struggling making a text to send.

using Android.App;
using Android.Widget;
using Android.OS;
using System;
using Android.Telephony;

namespace DrivePhone_GeniusHourProject
{
    [Activity(Label = "Drive Time!", MainLauncher = true, Icon = "@drawable/icon")]
    public class MainActivity : Activity
    {
        protected override void OnCreate(Bundle bundle)
        {
            base.OnCreate(bundle);

            // Set our view from the "main" layout resource
            SetContentView (Resource.Layout.Main);

            EditText SMS = FindViewById<EditText>(Resource.Id.SMS_Message);
            Button sendSMS = FindViewById<Button>(Resource.Id.Send_SMS);

            string SMS_Text = SMS.ToString();
            var smsTo = NSUrl.FromString();
            SmsMessage();

            smsTo = "815376377";
            sendSMS.Click += (object sender, EventArgs e) =>
            {

            }
        }
    }
}

Answer 1

My problem is that i'll do SmsManager. and then there isn't an option to send text. But in develoers website there is a public method called sendTextMessage(); But I can't use it in Visual studio.

In Xamarin, it is Android.Telephony.Gsm.SmsManager.SendTextMessage Method .

For example:

sendSMS.Click += (object sender, EventArgs e) =>
{
   var content = "**HERE GOES SMS CONTENT**";
   var destinationAdd = "**HERE GOES DESTINATION PHONE NUMBER**";

   Android.Telephony.Gsm.SmsManager sm = SmsManager.Default;
   sm.SendTextMessage(destinationAdd, null, content, null, null);
}

Don't forget to add permission in your manifest:

<uses-permission android:name="android.permission.SEND_SMS" />

If you want to receive sms, you also need the following permission:

<uses-permission android:name="android.permission.RECEIVE_SMS" /> 

Answer 2

For a better way to sent message install xam.plugin.Messaging( https://www.nuget.org/packages/Xam.Plugins.Messaging/ )

Then use the below code to send message

var smsMessenger = CrossMessaging.Current.SmsMessenger; if (smsMessenger.CanSendSms) smsMessenger.SendSms("+1234567890", "Well hello there from Xam.Messaging.Plugin");

Also please add the android.permission.SEND_SMS permission to your Android manifest file

For more details please go through https://github.com/cjlotz/Xamarin.Plugins/blob/master/Messaging/Details.md