My enum declaration:

```
public enum Note { A, A_SHARP, B, C, C_SHARP, D, D_SHARP,
    E, F, F_SHARP, G, G_SHARP;

    public String toString(Note note) {
        if (note == Note.A)
            return "A";
        else if (note == Note.A_SHARP)
            return "A#";
        else if (note == Note.B)
            return "B";
        else if (note == Note.C)
            return "C";
        else if (note == Note.C_SHARP)
            return "C#";
        else if (note == Note.D)
            return "D";
        else if (note == Note.D_SHARP)
            return "D#";
        else if (note == Note.E)
            return "E";
        else if (note == Note.F)
            return "F";
        else if (note == Note.F_SHARP)
            return "F#";
        else if (note == Note.G)
            return "G";
        else if (note == Note.G_SHARP)
            return "G#";
        else
            return "";
    }

    public Note getNext() {
        int index = ordinal();
        index++;
        if (index > values().length)
            return values()[0];
        else
            return values()[index];
    }
}

```

Whenever I call either of these two methods, my app crashes. Here is where I call them:

```
public void ChangeSound(View v) {
    note = note.getNext();
    tvSounds.setText(note.toString(note));
}

```

ChangeSound() is an onClick method for a button. If I remove both lines in ChangeSound(), the code works as it should, but if either of the two lines are in there, the app crashes on the button click. Any ideas why? Thanks in advance!!

EDIT\*\*
note is a variable of type Note

Thank you everyone! It was returning null (look at Jason C's answers (my comment)). All of this was helpful for me!