import android.content.Context;
    import android.content.Intent;
    import android.content.SharedPreferences;

    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;


    public class AddContacts extends AppCompatActivity {

SharedPreferences sharedPreferences;

SharedPreferences.Editor editor;

Button registerbtn;
EditText name1, num1, name2, num2, name3, num3;
String emname1,emname2,emname3;
int emnum1,emnum2,emnum3;

@Override

protected void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_addcontacts);


    sharedPreferences = this.getSharedPreferences("universe.sk.syndriveapp.addcontacts", Context.MODE_PRIVATE);
    editor = sharedPreferences.edit();

    registerbtn= findViewById(R.id.registerbtn);

    name1 = findViewById(R.id.name1);
    num1 = findViewById(R.id.num1);

    name2 = findViewById(R.id.name2);
    num2 = findViewById(R.id.num2);

    name3 = findViewById(R.id.name3);
    num3 = findViewById(R.id.num3);

    registerbtn.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {

            emname1 = name1.getText().toString();
            emnum1 = Integer.parseInt(num1.getText().toString());
            emname2 = name2.getText().toString();
            emnum2 = Integer.parseInt(num2.getText().toString());
            emname3 = name3.getText().toString();
            emnum3 = Integer.parseInt(num3.getText().toString());

            if (emname1.isEmpty() || emname2.isEmpty() || emname3.isEmpty()){
                Toast.makeText(AddContacts.this,"Please fill all details!",Toast.LENGTH_SHORT).show();
                onClick(view);
            }
            else {

                editor.putString("name1", emname1);
                editor.putInt("num1", emnum1);
                editor.putString("name2", emname2);
                editor.putInt("num2", emnum2);
                editor.putString("name3", emname3);
                editor.putInt("num3", emnum3);

                editor.apply();
                Toast.makeText(AddContacts.this,"Registration Success",Toast.LENGTH_SHORT).show();
                startActivity(new Intent(AddContacts.this,NavigationActivity.class));
            }


                        }});


         }

}