private void buttonDodajAutomobil_Click(object sender, EventArgs e)
{
if (comboMarka.SelectedIndex != 0 && comboModel.SelectedIndex != 0 && comboTip.SelectedIndex != 0 && tbCijena.Text != "" && labelSnaga.Text != "")
{
Automobil auto = new Automobil();
auto.UpisiNoviAutomobil(Convert.ToInt32(label4.Text), Convert.ToInt32(labelSnaga.Text), rtbOpis.Text, Convert.ToInt32(tbCijena.Text));
MessageBox.Show("Uspješno ste dodali novi automobil!");
comboMarka.SelectedIndex = 0;
comboModel.SelectedIndex = -1;
comboTip.SelectedIndex = 0;
tbCijena.Text = "";
trackBar1.Value = 0;
rtbOpis.Text = "";
}
}