![]() The CrossBasic name was trademarked by another company, so the product was renamed REALbasic. A public beta was released in April 1996. CrossBasic got its name from its ability to compile the same programming code for the classic Mac OS and the Java virtual machine (although the integrated development environment was Mac only). In 1996 FYI Software, founded by Geoff Perlman, bought CrossBasic, which had been marketed by its author Andrew Barry as a shareware product. Xojo uses a proprietary object-oriented language. of Austin, Texas for software development targeting macOS, Microsoft Windows, Linux, iOS, Android, the Web and Raspberry Pi. (For information about constructors and destructors, see the section Constructors and Destructors.) When you access it, it gives you the current number of instances of the class.The Xojo programming environment and programming language is developed and commercially marketed by Xojo, Inc. Each time you create or destroy an instance of the class, you can increment the value of the shared property in its constructor and decrement it in its destructor. For example, if you are using an instance of a class to keep track of items (e.g., persons, merchandise, sales transactions, and so forth) you can use a shared property as a counter. Generally speaking, shared properties are an advanced feature that you only need in special cases. It is important to understand that if you change the value of a shared property, the change is available to every usage of the shared property. ![]() In many ways, it works like a module property. A shared property is global and can be accessed from anywhere its scope allows. And with classes, you have the option to create versions that don 't allow access to the source code of the class, allowing you to create classes you can share or sell to others.Ī shared property (sometimes called a class property) is like a regular property, except it belongs to the class, not an instance of the class. You can use classes to create custom controls. ![]() More Control - Classes give you more control than you can get by adding code to the event handlers of a control in a window. Changes to the code in a class are automatically used anywhere where the class is used.Įasier Debugging - The less code you have, the less code there is to debug. By storing one copy of the code, when you need to make changes, you'll spend less time tracking down all those places in your project where you are using the same code. If you have basically the same code copied in several places of your projects, you have to keep that in mind when you make changes or fix bugs. Smaller Projects and Apps - Because classes allow you to store code once and use it over and over in a project, your project and the resulting app is smaller in size and may require less memory.Įasier Code Maintenance - Less code means less maintenance. ![]() If you create a class based on the DesktopButton control and then add your code to that class, any usage (instances) of that custom class will have that code. Classes store the code once and refer to the object (like the DesktopButton) generically so that the same code can be reused any number of times without modification. If you want to use the same code with another DesktopButton, you need to copy the code and then make changes to the code in case it refers to the original DesktopButton (since the new DesktopButton will have a different name than the original). Reusable Code - When you directly add code to a DesktopButton on a Window to customize its behavior, you can only use that code with that one DesktopButton. Classes are the fundamental building blocks of object-oriented programming. But unlike a module, a class provides better code reuse. In its simplest form, a class is a container of code and data much like a module. Reporting bugs and making feature requests.Understanding classes, instances and references.
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