Menambah kontrol tombol , teks dan label

Control ComboBox: name = cmbKategori

Control TextBox: name = txtNamaBarang, text = dikosongkan

Control TextBox: name = txtJumlah, text = '0'

Control TextBox: name = txtHargaJual, text = '0'

Control Label: name = lblKategori, text = 'Kategori'

Control Label: name = lblNamaBarang, text = Nama Barang'

Control Label: name = lblJumlah, text = 'Jumlah'

Control Label: name = lblHargaJual, text = 'Harga Jual'