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Fix for Xcode's indiscernible highlighting of inline errors?
Does anyone know how to change the color of the in-line highlighting for warnings and errors in Xcode 4? With almost every theme, the yellow warning highlight makes the underlying code impossible to read. Example picture
Just came across this, which seems to be able to modify some of Xcode's behaviors by creating some sort of plugin. Maybe one can be developed to change text highlight color. http:/github.com/davekeck/Xcode-4-Fixins
Update:
I've finally managed to implement a Xcode "fixin" to do it.
You just need to open the project and build it. Doing so will install an Xcode plugin called "XCFixin_CustomizeWarningErrorHighlights.xcplugin" into ~/Library/Application Support/Developer/Shared/Xcode/Plug-ins. You can of course customize the colors to your liking.
Get the "fixin" here:
https://github.com/armadillu/Xcode-4-Fixins/tree/master/XCFixin_CustomizeWarningErrorHighlights
There is no (official) way to do this and I believe that it's like that for a reason... We all know how much attention to details and UI paradigms Apple is paying. An error colored in Green for example would break that paradigm and possibly confuse the user. That being said, I think that a (somewhat) solution would be instead of recoloring the warning/error bubbles, to recolor the theme in such a way that every color would make a strong contrast with red/yellow (ie avoid reddish/yellowish tones) tints.
there is no options which you can change color of warning and errors.its inbuilt with Theme you are using for xcode. but you can change the style from xcode->fonts & colors and select different theme.
来源：https://stackoverflow.com/questions/7574388/how-does-one-change-the-color-for-text-highlighting-in-xcode-4-for-warnings-and