Hi I'm a newbie here in salesforce stackexchange, so please bear with me. :)
Assuming I have three custom objects: Order__c, OrderItem__c, and Product__c.
My plan is to create three sections in the Order Form (Order__c) and these are the sections: Order Information, Delivery Information, and Product Information. In the Product Information section, there's an Add button, and upon clicking this button, rows for adding products with corresponding quantity, unit price, discount (per product), and total price (per product) will appear.
Upon product selection and input of quantity and discount, Grand Total (From Order Information section) will automatically compute the total of the selected items in the Product Information Section. The idea is that before saving the order form, I will already have the idea of how much I'm going to pay for this transaction.
How can I do this without clicking New Button from Order Item, and there add product?
What I have right now is the usual process, meaning I'll have to save order first (without product info section). After the order form is saved, I'll have to look to OrderItem related list, and from there, add the products. This process takes much of my time, that's why I'm planning to have a new way.