Inside Apple's new Xcode 4 development tool
Now including Interface Builder
Apple's Xcode Mac OS X developer tools, adapted alongside the iPhone 2.0 SDK to also create iOS mobile apps, originally included Project Builder for working with code and Interface Builder for laying out a program's graphical user interface and mapping elements of the GUI to the code that made it functional.
Back in the late 80s, the original developer of Interface Builder, Jean-Marie Hullot, showed the graphical development concept to Apple but was wooed away to Steve Jobs' NeXT Computer, which made the advanced GUI builder part of its development tools.
Interface Builder was used to rapidly develop Tim Berners-Lee's WorldWideWeb browser at CERN. Apple later acquired the technology when it bought NeXT in 1996, making it part of the Mac OS X development tool package with Project Builder, which the company has since renamed Xcode.
In Xcode 4, Interface Builder is folded into the revamped Project Builder-based IDE to create a single tool for creating both the appearance and the functionality of applications. The deep integration between the two components provides a variety of improvements in developing mobile and desktop applications.
Graphical elements can now bind their outlets and actions right into source code using a graphical drag and drop gesture. A new Assistant feature in Xcode 4 allows developers to work on the GUI and source code at the same time (below).
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