Write your own methods for objects
A new command is at your disposal allowing you to use formulas in your code. You can now encapsulate them in objects and call them when needed. There’s no more need to write your code as text. Now you can just pass your formula in your command and that’s it! This is a great addition, since your code isn’t text, you can benefit from Syntax highlighting and all the other advanced functionalities of the code editor!
Write generic code with ORDA
ORDA was one of the major announcements of 4D Summit 2018, opening a world of new possibilities in 4D. To learn more about ORDA and its benefits, check out this post to see how ORDA will change the way you work.
Times inside objects… (and everywhere else)
Objects are at it again, continuing to demonstrate their utility to ease your life as a developer.
Using time (or duration) values inside of objects is now smoother and more intuitive. Beginning with 4D v17, times inside objects are set as seconds – and not milliseconds!
How to display a multilevel collection in different list boxes!
Starting with 4D v17, the content of a multilevel collection can easily be displayed in different list boxes. Meaning that you can bind several list boxes to display nested details … without a single line of code! This can be achieved by simply using an object or a collection as the data source for another list box!
With the new list box collection type, the “Current item” and “Selected items” properties have been added. Keep in mind that the “Current item” property allows you to get an object, while the “Selected item” property returns a collection.
How to create a generic form with dynamic forms
Imagine that your database contains several tables of types or categories. These tables are very simple, often with only an identifier and a text field. For demonstration purposes, let’s say it’s a shoe management database. To qualify the products, we need to define their type, color, pattern, material, season and so on.
It’s cumbersome to manage each of these tables in a list form and an input form and associated methods. In this case, the use of a generic form is essential to avoid duplication and simplify maintenance.
And that’s where dynamic forms and JSON pointers are come in handy!
Compute statistics on entity selections with ORDA
ORDA provides a great feature to channel data through filters and get aggregated values, by including a set of easily-understood aggregation operations that examine and perform calculations on the data sets. For example, the sum, average, count, min, and max methods are used to perform the operations which their names describe!
Get machine hardware information
4D v17 goes a step further to let you create a customized server administration dialog. Following the ability to retrieve information about users & processes, getting all runtime information about 4D Web server, as well as details about the active license, you now have the ability to also retrieve all of the hardware and system details for the machine running your 4D server.
Do you need to know what OS is being used, what processor(s), how much RAM is available, etc.? Just call the new Get system info command, locally or remotely! And that’s not all, this command can be extremely useful for quickly diagnosing and solving any problems that may arise.
Logical operations on entity selections
The ORDA series continues! In this blog post we’ll see how to use logical operators on entity selections!
These operations allow you to get intersections, unions, or differences between two entity selections like you can with classic 4D sets.
Handle entities in an entity selection
FIRST RECORD, LAST RECORD, NEXT RECORD, PREVIOUS RECORD; does that ring any bells? I bet it does. You’ve already been using them to handle selections! ORDA provides useful and familiar methods to navigate through entities in an entity selection – and obviously, some perks!
For starters, you can handle several entity selections at the same time and navigate through them independently, whereas normally you can only manage a single ‘current selection’ per table. That’s precisely what we’re going to see in this blog post.
Working with ORDA optimistic locking
4D v17 introduces ORDA, a major evolution in 4D which is opening a world of new possibilities for 4D developers. One of the benefits of using ORDA is related to record locking, because ORDA offers a choice between optimistic and pessimistic locking. After having introduced the ORDA locking mechanisms, we continue the ORDA series so you can discover how to work efficiently with optimistic locking with ORDA.
Contact us
Got a question, suggestion or just want to get in touch with the 4D bloggers? Drop us a line!
* Your privacy is very important to us. Please click here to view our Policy