How to make a SetOnClickListener only happening when its EditText's are different from zero

Question

I want to make a calculator that uses the button Add to take 2 different EditText's and add them, showing on a Toast. But when I click directly on the button without typing any value, the app crashes. I would be very glad to hear a solution to this. I tried with an if comparing with null. Here's the code:

if(num1 != null && num2 != null){

    som.setOnClickListener(         
        new View.OnClickListener(){

        @Override
        public void onClick(View v){


            Double valor1 = Double.parseDouble(num1.getText().toString());
            Double valor2 = Double.parseDouble(num2.getText().toString());

            Double Soma = valor1+valor2;

            Toast.makeText(MainActivity.this,"A soma é: "+Soma, Toast.LENGTH_LONG).show();


                                    }
    });
}

Answer 1

put if(! num1 .getEditableText().toString().matches("") && !num2 .getEditableText().toString().matches("")) in your onClick method