Error making calling methods from one class through another

Question

My application crashes when I write this code below, I am trying to stop the Login Class in the Registration Class and access the Login class methods through the Registration class.

    ca.getLogar().setLogin(logCad.getText().toString());
    ca.getLogar().setSenha(senhaCad.getText().toString());

Does anyone have any idea how to solve this ? These are the access method and attributes in the login class

private LoginClasse logar;

    public LoginClasse getLogar() {
        return logar;
    }

    public void setLogar(LoginClasse logar) {
        this.logar = logar;
    }

Login class

    public class LoginClasse {
    
        private String login;
        private String senha;
    
    
    
        public String getLogin() {
            return login;
        }
    
        public void setLogin(String login) {
            this.login = login;
        }
    
        public String getSenha() {
            return senha;
        }
    
        public void setSenha(String senha) {
            this.senha = senha;
        }
    }

Register Class

public class CadastroClasse {

    private String nome;
    private String cpf;
    private String tel;
    private String end;
    private String cep;
    private String email;

    private LoginClasse logar;

    public LoginClasse getLogar() {
        return logar;
    }

    public void setLogar(LoginClasse logar) {
        this.logar = logar;
    }

    public String getNome() {
        return nome;
    }

    public void setNome(String nome) {
        this.nome = nome;
    }

    public String getCpf() {
        return cpf;
    }

    public void setCpf(String cpf) {
        this.cpf = cpf;
    }

    public String getTel() {
        return tel;
    }

    public void setTel(String tel) {
        this.tel = tel;
    }

    public String getEnd() {
        return end;
    }

    public void setEnd(String end) {
        this.end = end;
    }

    public String getCep() {
        return cep;
    }

    public void setCep(String cep) {
        this.cep = cep;
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }
}

      

Registration method that is responsible for the problem

    public void Cadastrar(View view)
        {
            CadastroClasse ca=new CadastroClasse();
        
    
            ca.getLogar().setLogin(logCad.getText().toString());
            ca.getLogar().setSenha(senhaCad.getText().toString());
            ca.setNome(nome.getText().toString());
            ca.setCpf(cpf.getText().toString());
            ca.setTel(tel.getText().toString());
            ca.setEnd(end.getText().toString());
            ca.setCep(cep.getText().toString());
            ca.setEmail(email.getText().toString());
    
            startActivity(new Intent(Cadastro.this,MainActivity.class));
    
        }

Answer 1

Your Registration class has the private Loginclasse attribute log in, but you do not initialize it at any time. With this, you are trying to call setLogin a variable that has not been initialized, and this ends up generating an error.

To solve this you could, modify your main and call setLog the register class by passing a Loginclasse object, example:

public void Cadastrar(View view)
        {
            CadastroClasse ca=new CadastroClasse();
        
            ca.setLogar(LoginClasse());//linha adicionada por mim
            ca.getLogar().setLogin(logCad.getText().toString());
            ca.getLogar().setSenha(senhaCad.getText().toString());
            ca.setNome(nome.getText().toString());
            ca.setCpf(cpf.getText().toString());
            ca.setTel(tel.getText().toString());
            ca.setEnd(end.getText().toString());
            ca.setCep(cep.getText().toString());
            ca.setEmail(email.getText().toString());
    
            startActivity(new Intent(Cadastro.this,MainActivity.class));
    
        }

Another way would be to instantiate this class in the constructor of the Register class, example

public class CadastroClasse {

    private String nome;
    private String cpf;
    private String tel;
    private String end;
    private String cep;
    private String email;

    private LoginClasse logar;
    
    public CadastroClasse(){
        logar = LoginClasse()
    }
   
    //resto do codigo

Doing one of these ways you will be initiating the log variable and will be able to access the Loginclasse class methods.