This script shows stock of selected item from sales screen and stops selling out of stock item

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Below script creates a button on sales screen to to show stock of selected item.
Add the below line Ticket.Buttons:

<button key="button.print" name="stock" code="Script.Stock" shortcut="F9"/>

Create a new resource, Script.Stock, and add the below line:

javax.swing.JOptionPane.showMessageDialog(null, "Stock: " + sales.getStock(ticket.getLine(sales.getSelectedIndex()).getProductID()) + "     " + "Buy Price: " + ticket.getLine(sales.getSelectedIndex()).printPriceBuy());

To stop selling out of stock items, add below lines in event.addline and event.setline

event.addline

if(sales.getStock(line.getProductID())==0 || sales.getStock(line.getProductID())-line.getMultiply()<=0)
{
 javax.swing.JOptionPane.showMessageDialog(null, "There is no stock of this item.");
     return "Cancel";
}

event.setline

if(sales.getStock(line.getProductID())==0 || sales.getStock(line.getProductID())-line.getMultiply()<0)
{
 javax.swing.JOptionPane.showMessageDialog(null, "There is no stock of this item.");
     return "Cancel";
}

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