for Sawser

package com.example.igor.myregex;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
/*
    All this "PROGRAM" does is to determin if the userInput was numbers or not!
*/
public class MainActivity extends AppCompatActivity
{
    EditText ip;//<-- set up variable for your EditText (that exists in XML)
    Button btn; //<-- set up variable for your button (that exists in the XML)

     //in here you will connect your Java variable with the XML tags (using the tags ID's)
    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        ip = (EditText)findViewById(R.id.idTextIP);//<--connect EditText Variable with EditText tag ID (that located in the XNL)
        btn = (Button)findViewById(R.id.idBtn); //<-- connect Button Variable with the Button tag ID (that located in the XML)
    }
     //this method will activate the following actions after pressing the button on the screen!
     //NOTE! That if you wish to make this method to activate on button click you need to go to the button TAG in XML
     //and write onClick and in it write THIS (onConfirm) method name!
    public void onConfirm(View v)//<-- do not forget to insert the View v or else Java wont that you wish to use this method
     //on XML Tag
    {
        String str = idText.getText().toString(); //get string from the editText

        //just like discribed aboe ^ create String variable inside the method that will contain all of users input in the EditText!

        boolean isNumeric;//<-- set boolean Variable inside the method and leave it empty (By Defualt its false [AKA isNumeric=false])
        isNumeric = str.matches("[0-9]{3,}+"); // enter regex here

        //now just like described above ^ you equal the isNumeric (boolean) varialbe with the str (String) variable while
        //the str variable is used with .matches(); method that CHECKS if the String input matches the Regex you set!

        Toast.makeText(this, "is Numeric "+isNumeric, Toast.LENGTH_SHORT).show();

        //now print it all in a toast to see if the isNumeric true or false ( depends on users input in the EditText!)

    }
}