Object-oriented user interface

In computing, an object-oriented user interface (OOUI) is a type of user interface based on an object-oriented programming metaphor. In an OOUI, the user interacts explicitly with objects that represent entities in the domain that the application is concerned with. Many vector drawing applications, for example, have an OOUI – the objects being lines, circles and canvases. The user may explicitly select an object, alter its properties (such as size or colour), or invoke other actions upon it (such as to move, copy, or re-align it). If a business application has any OOUI, the user may be selecting and/or invoking actions on objects representing entities in the business domain such as customers, products or orders. Many observers have hypothesized that Smalltalk user interface and the Smalltalk language are separable innovations. Consequently, most systems influenced by the Smalltalk user interface have been engineered without resorting to Smalltalk’s implementation approach. At Apple, after using Pascal to implement six initial applications for Lisa, we discovered compelling reasons to change our programming language to incorporate more ideas from Smalltalk. Lisa applications are now written in the language Clascal, an extension of Pascal featuring objects, classes, subclasses, and procedure invocation by message-passing. In computing, an object-oriented user interface (OOUI) is a type of user interface based on an object-oriented programming metaphor. In an OOUI, the user interacts explicitly with objects that represent entities in the domain that the application is concerned with. Many vector drawing applications, for example, have an OOUI – the objects being lines, circles and canvases. The user may explicitly select an object, alter its properties (such as size or colour), or invoke other actions upon it (such as to move, copy, or re-align it). If a business application has any OOUI, the user may be selecting and/or invoking actions on objects representing entities in the business domain such as customers, products or orders. Jakob Nielsen defines the OOUI in contrast to function-oriented interfaces: 'Object-oriented interfaces are sometimes described as turning the application inside-out as compared to function-oriented interfaces. The main focus of the interaction changes to become the users' data and other information objects that are typically represented graphically on the screen as icons or in windows.'