package example.javatpoint.com.sumoftwonumber;  
  
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 MainActivity extends AppCompatActivity {  
    private EditText edittext1, edittext2;  
    private Button buttonSum;  
  
    @Override  
    protected void onCreate(Bundle savedInstanceState) {  
        super.onCreate(savedInstanceState);  
        setContentView(R.layout.activity_main);  
  
        addListenerOnButton();  
    }  
  
    public void addListenerOnButton() {  
        edittext1 = (EditText) findViewById(R.id.editText1);  
        edittext2 = (EditText) findViewById(R.id.editText2);  
        buttonSum = (Button) findViewById(R.id.button);  
  
        buttonSum.setOnClickListener(new View.OnClickListener() {  
            @Override  
            public void onClick(View view) {  
                String value1=edittext1.getText().toString();  
                String value2=edittext2.getText().toString();  
                int a=Integer.parseInt(value1);  
                int b=Integer.parseInt(value2);  
                int sum=a+b;  
                Toast.makeText(getApplicationContext(),String.valueOf(sum), Toast.LENGTH_LONG).show();  
            }  
        });  
    }  
}