1) Add the AutoScrollLabel class files to your project and add an outlet for the scrolling text. Save the files. Otherwise the next steps won't work.
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2) Add a UIScrollView to your view using Interface Builder. Then, using the Inspector, change the class type to AutoScrollLabel.
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3) Right click on the scrolling label and assign a referencing outlet to be the outlet you added in step 1.
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4) Add code to your view controller class to set the text and other properties for the autoScrollLabel.
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5) Compile your project and the autoScrollLabel should now be scrolling like a marquee.
And in case that's not clear, here's a (silent) video demonstrating the same thing. (You might want to bump the video to fullscreen so the text is readable.) Enjoy!
AutoScrollLabel Demo from Brian Stormont on Vimeo.