onSubmit()
  {
    this.http.post('some/api',
    JSON.stringify({
      user_name: this.login_form.value.user_name,
      password: this.login_form.value.password
    }),
    this.options
    )
    .subscribe(data =>  {
      this.getUserData = data[0];

      this.user = {
        Ime: data['Ime'],
        Prezime: data['Prezime'],
        Username: data['Username'],
        Sifra: data['Sifra'],
        Broj_telefona: data['Broj_telefona'],
        jmbg: data['jmbg'],
        Nivo: data['Nivo']
      }
    console.log(this.user);
    console.log(this.getUserData);
    });
  }