This document provides instructions for installing and using Xcode on Mac computers. It summarizes that there will be no computer science lecture the following week, and that Xcode is now available on library Macs. It then demonstrates how to install Xcode from the App Store, create a new project, write and run sample code, and use features like autocompletion, static analysis, and the debugger.

1. Computer Science Large Practical:
Programming with Xcode
Stephen Gilmore
School of Informatics
Friday 19th October, 2012
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2. News
There will be no CSLP lecture next week. The next CSLP lecture will
be on Friday 2nd November.
As of Tuesday, Xcode is now available on all the Open Access Lab
Apple Macs in the Main Library in George Square.
If you are developing on the Macs in the library you do not need to
install Xcode.
We see first how to install Xcode if you are working on your (Mac)
laptop.
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3. Xcode is available from the App Store
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4. Click to install
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5. Supply your Apple ID password
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6. The button will change to “Installing”
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7. Foo
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8. Accept the License Agreement
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9. Some components may be updated
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10. Requires system permission
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11. Installing ...
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12. Installing ...
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13. Installation complete
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14. Welcome screen
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15. Create a new project
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16. Many options, including iOS projects
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17. Choose an OS X application
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18. Choose a command-line tool
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19. Choose options
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20. Choose options
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21. Choose Foundation for Objective-C
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22. Can choose to create a git repository
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23. Project main screen
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24. Project has sample “Hello World” code
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25. Autocompletion suggests options
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26. Autocompletion suggests options
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27. Autocompletion suggests options
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28. Static analysis warns about code problems
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29. Autocompletion works on literals too
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30. Deliberately seeding a bug, overwriting a needed value
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31. Static analysis warns about format string errors
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32. Fixing the format string error
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33. Running the code (first time)
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34. Requires authentication
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35. Build succeeded
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36. Output in console
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37. Using static analysis to find errors (choose Analyze)
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38. Errors detected: value stored to ‘s’ is never read
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39. Xcode decides to download libraries
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40. Xcode decides to download libraries
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41. Decide to initialise string
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42. Looking for appropriate init method
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43. Looking for appropriate init method (initWithString: ?)
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44. Using “initWithString:” with a literal is redundant
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45. Checking documentation
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46. Code compiles without warnings — even with Analyze
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47. Produces expected result
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