如何在Android studio中设置注册表的onClick验证

public class MainActivity extends AppCompatActivity {

    private EditText usernameEditText;
    private EditText passwordEditText;
    private Button registerButton;

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

        usernameEditText = findViewById(R.id.usernameEditText);
        passwordEditText = findViewById(R.id.passwordEditText);
        registerButton = findViewById(R.id.registerButton);

        registerButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                validateInput();
            }
        });
    }

    public void validateInput() {
        String username = usernameEditText.getText().toString();
        String password = passwordEditText.getText().toString();

        if (username.isEmpty() || password.isEmpty()) {
            Toast.makeText(this, "请输入用户名和密码", Toast.LENGTH_SHORT).show();
        } else if (password.length() < 6) {
            Toast.makeText(this, "密码长度不能少于6位", Toast.LENGTH_SHORT).show();
        } else {
            // 验证通过，执行相应的操作
            Toast.makeText(this, "注册成功", Toast.LENGTH_SHORT).show();
            // 其他操作...
        }
    }
}