null pointer exception when trying to access class

i am trying to get the value from my methods and display it in another class as a toast (Just to make sure my methods work). I am getting a null pointer exception that i cant seem to figure out, i've tried multiple differnt things. I've even tried giving my Strings values of "This" and "That". Then my log cat tells me

04-05 21:17:29.633: E/AndroidRuntime(18838): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.cerealBarApps/com.cerealBarApps.Testing}: android.content.res.Resources$NotFoundException: String resource ID #0x0

This is the class i want to use to run everything.

public class Testing extends Activity {

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        String Testeroni = "This";
        String Testerhynocerous = "That";

        LoginTest test = new LoginTest();

        Toast.makeText(getApplicationContext(), (test.TestUsername(Testeroni)),
                Toast.LENGTH_SHORT).show();

        Toast.makeText(getApplicationContext(),
                (test.TestPassword(Testerhynocerous)), Toast.LENGTH_SHORT)
                .show();

    }
}

This is the class that i am calling to run methods from.

public class LoginTest {

    // 0 = Username length is less than 4 or greater than 15
    // 1 = Username character is not a letter/or digit
    // 9 = Everything is okay in username :)
    public int TestUsername(String username) {
        if (username.length() <= 4 || username.length() >= 15) {

            return 0;
        }

        for (int i = 0; i < username.length(); i++) {
            if (Character.isDigit(username.charAt(i))
                    || Character.isJavaLetter(username.charAt(i))) {
                System.out.println("");
                // Do Nothing
            } else

                return 1;
        }
        return 9;
    }



        // 2 = Passowrd length is less than 4 or greater than 15
        // 3 = Password character is not a digit
        // 8 = Everything is okay in password :)
        public int TestPassword(String password) {
            if (password.length() <= 4 || password.length() >= 15) {
                return 2;
            }

            for (int i = 0; i < password.length(); i++) {
                if (Character.isDigit(password.charAt(i))
                        || Character.isJavaLetter(password.charAt(i))) {
                    System.out.println("");
                    // Do Nothing
                } else
                    return 3;
            }
            return 8;
        }
    }

Answers


these code:

Toast.makeText(getApplicationContext(), (test.TestUsername(Testeroni)),
            Toast.LENGTH_SHORT).show();

    Toast.makeText(getApplicationContext(),
            (test.TestPassword(Testerhynocerous)), Toast.LENGTH_SHORT)
            .show();

have some problem, test.TestUsername(Testeroni) and test.TestPassword(Testerhynocerous) the return type is int, so it think like the string res id, so if can change to this:

 Toast.makeText(getApplicationContext(), (""+test.TestUsername(Testeroni)),
            Toast.LENGTH_SHORT).show();

    Toast.makeText(getApplicationContext(),
            (""+test.TestPassword(Testerhynocerous)), Toast.LENGTH_SHORT)
            .show();

The problem is here:

Toast.makeText(getApplicationContext(), (test.TestUsername(Testeroni)),
            Toast.LENGTH_SHORT).show();

The TestUsername returns an int and it is interpreted as resource id which of course is not valid.

Change it to:

Toast.makeText(getApplicationContext(), String.valueOf((test.TestUsername(Testeroni))),
            Toast.LENGTH_SHORT).show();

Need Your Help

Android: How to show a dialog after user clicks “Okay” on a previous dialog

android dialog

How come the AlertDialog that has the title "Location was saved to file" doesn't show up? It is the one that should be displayed after the user presses Okay on the first dialog.

Linux buffer cache for DVD/FUSE?

linux caching filesystems linux-kernel vfs

I want to know whether the buffer cache in Linux kernel is present for file systems like UDF for DVD and FUSE?

About UNIX Resources Network

Original, collect and organize Developers related documents, information and materials, contains jQuery, Html, CSS, MySQL, .NET, ASP.NET, SQL, objective-c, iPhone, Ruby on Rails, C, SQL Server, Ruby, Arrays, Regex, ASP.NET MVC, WPF, XML, Ajax, DataBase, and so on.