For opentaps Open Source ERP + CRM version 1.4, we have a new “editable grid” based on the Google Web Toolkit that should make entering invoices and orders a lot easier. Here’s an example of how it works.
As you can see, there are now two ways to enter new items into invoices. You can use the traditional form to enter a new item, and then the server will refresh the page with the list of updated items. Or, you can switch to the new [Grid View] and type in the products or the invoice item types and their quantities. opentaps will make a server-side call to get the price and insert it into the grid, and you can keep going without waiting after entering each new item. opentaps calculates the invoice total from the items you have entered into the grid, but these items are kept locally in your browser and not stored on the server until you click on [Save All].
Of course, the old forms are still there, and you can always switch back to the [Full View]. The full view is better if you need to enter other information, such as the accounting tags, for your invoice items, or if you have a modified version of these forms from older versions of opentaps. opentaps will remember whether you prefer the grid or the full view and pull up the correct one when you get to the create invoice screen by default.