c++ - Qt When will the dialog return QDialog::Rejected -

i'm in trouble. have qdialog login form. when log in, form closes , mainwindow appear. login fine when closes returns qdialog::rejected.

what can prevent return of qdialog::rejected? , when return qdialog::rejected?

code when log in :

void login::on_cmdlogin_clicked() {      if( ui->txtusernamelogin->text().isempty()  || ui->txtpasslogin->text().isempty() )     {             qmessagebox::critical(this, "vocabulary trainer", "please fill in both textboxes.", qmessagebox::ok);             return;     }     user user(filepath + "/users.txt");     if ( user.checkpassword( ui->txtusernamelogin->text(), ui->txtpasslogin->text() ))     {         username = ui->txtusernamelogin->text();         close();     }     else         qmessagebox::warning(this, "vocabulary trainer", "sorry, password incorrect.\nplease type in correct password.", qmessagebox::ok); } 

main() :

mainwindow w;   //real window login lg(0);    //login window  lg.set_path(workspace_path); lg.setmodal(true); if(lg.exec() == qdialog::rejected)     qmessagebox::critical(0, "rr", "", qmessagebox::ok); else     w.show();   //shows real window 

it'll rejected.

try call done(qdialog::accepted); instead close(); in login::on_cmdlogin_clicked()