How to write a android code where I can get registration ID

Before i was not understood how its GCM Notifications work. I google it. and i found the following step and then i understood.

steps are give below.

1-First Create a developer account.

2-From that developer account we can get 1) Sender ID/Project ID 2) API Key.

3- To send message on each client we need to have their Device Registration ID

' This one i don't know how to get, for that i used GCM Server Helper in Play store. on that apps i put project ID then

this apps give me registration ID

then i create small ASP.Net apps code behind file Vb.net

and i pass four thing. 1) Sender/Project ID 2) API Key 3) Registration ID 4) Message.

then now i understood how popup notification works. When data inserted into sql table then we need to tell GCM services to send message to registered client.

Now what my problem are:

1) How to do the programe in android where i can pass the send ID/Project ID and API parameter to GCM service and get the Registration ID

2) Then i want to save this registration ID in sql becoz i will tell GCM to send message to particular client.

Below is perfectly working code in asp.net.

Private Sub Frm_SendNotification()

RegId = ""

ApplicationID = ""

SENDER_ID = ""

Dim value = TextBox1.Text

'message text box

Dim tRequest As WebRequest

tRequest = WebRequest.Create("https://android.googleapis.com/gcm/send")

tRequest.Method = "post"

tRequest.ContentType = "application/x-www-form-urlencoded;charset=UTF-8"

tRequest.Headers.Add(String.Format("Authorization: key={0}", ApplicationID))

tRequest.Headers.Add(String.Format("Sender: id={0}", SENDER_ID))

'Data post to the Server

Dim postData As String = (Convert.ToString("collapse_key=score_update&time_to_live=108&delay_while_idle=1&data.message=" + value + "&data.time=" + System.DateTime.Now.ToString() + "&registration_id=") & RegId) + ""

Console.WriteLine(postData)

Dim byteArray As [Byte]() = Encoding.UTF8.GetBytes(postData)

tRequest.ContentLength = byteArray.Length

Dim dataStream As Stream = tRequest.GetRequestStream()

dataStream.Write(byteArray, 0, byteArray.Length)

dataStream.Close()

Dim tResponse As WebResponse = tRequest.GetResponse()

dataStream = tResponse.GetResponseStream()

Dim tReader As New StreamReader(dataStream)

Dim sResponseFromServer As [String] = tReader.ReadToEnd()

'Get response from GCM server

Label1.Text = sResponseFromServer

'Assigning GCM response to Label text

tReader.Close()

dataStream.Close()

tResponse.Close()

End Sub