Question

I want to make that when the user click the button below and the String on EditText is empty, it shows a dialog.
So I made this method, but unfortunately rather than showing a Dialog Box, the app crashed. There’s no problem with the Dialog box method, the problem is the IF function doesn’t read what I requested properly.

Anybody has the solution for this?

Here’s my method:

public void onClick(View v) {

if(v == launchSimplePayment) {
            String amount = paymentAmount.getText().toString();
            System.out.println(amount);
            if (amount == "")
            {
                errorDialog();
            }
            else
            {
                System.out.println(amount);
                // Use our helper function to create the simple payment.
                PayPalPayment payment = exampleSimplePayment(); 
                // Use checkout to create our Intent.
                Intent checkoutIntent = PayPal.getInstance().checkout(payment, this, new ResultDelegate());
                // Use the android's startActivityForResult() and pass in our Intent. This will start the library.
                startActivityForResult(checkoutIntent, request);

            }
}

Answer 1

Change this

if (amount == "")

with this

if (amount.equals(""))

Remember that the operator == compares references, not the content!