Untitled

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;

public class MainActivity extends AppCompatActivity {

    // Declare the views that we will be using in our layout
    EditText etNum1;
    EditText etNum2;
    Button btnAdd;
    Button btnSubtract;
    Button btnMultiply;
    Button btnDivide;
    Button btnClear;
    EditText etResult;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        // Initialize the views
        etNum1 = (EditText) findViewById(R.id.etNum1);
        etNum2 = (EditText) findViewById(R.id.etNum2);
        btnAdd = (Button) findViewById(R.id.btnAdd);
        btnSubtract = (Button) findViewById(R.id.btnSubtract);
        btnMultiply = (Button) findViewById(R.id.btnMultiply);
        btnDivide = (Button) findViewById(R.id.btnDivide);
        btnClear = (Button) findViewById(R.id.btnClear);
        etResult = (EditText) findViewById(R.id.etResult);

        // Set the click listeners for the buttons
        btnAdd.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                // Perform the addition and display the result
                double num1 = Double.parseDouble(etNum1.getText().toString());
                double num2 = Double.parseDouble(etNum2.getText().toString());
                double result = num1 + num2;
                etResult.setText(Double.toString(result));
            }
        });

        btnSubtract.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                // Perform the subtraction and display the result
                double num1 = Double.parseDouble(etNum1.getText().toString());
                double num2 = Double.parseDouble(etNum2.getText().toString());
                double result = num1 - num2;
                etResult.setText(Double.toString(result));
            }
        });

        btnMultiply.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                // Perform the multiplication and display the result
                double num1 = Double.parseDouble(etNum1.getText().toString());
                double num2 = Double.parseDouble(etNum2.getText().toString());
                double result = num1 * num2;
                etResult.setText(Double.toString(result));
            }
        });

        btnDivide.setOnClickListener(