private void barangToolStripMenuItem_Click(object sender, EventArgs e)
 {
     if (frmBarang == null)
     {
         frmBarang             = new FormMasterBarang();
         frmBarang.FormClosed += new FormClosedEventHandler(frmBarang_fromClosed);
         frmBarang.ShowDialog();
     }
     else
     {
         frmBarang.Activate();
     }
 }
 void frmBarang_fromClosed(object sender, FormClosedEventArgs e)
 {
     frmBarang = null;
 }