File is Out of sync Using 1.7 requires compiling with Android 4.4 (KitKat); currently using API 16

Question

[2014-05-05 09:05:20 - android-support-v7-appcompat] File is Out of sync
[2014-05-05 09:05:22 - android-support-v7-appcompat] Using 1.7 requires compiling with Android 4.4 (KitKat); currently using API 16

what I must do?

Answer 1

Changing Compiler compliance level in Java Compiler settings to 1.6 solved the problem for me. (Project Properties -> Java Compiler -> Enable project specific settings -> Compiler compliance level -> 1.6)

Answer 2

I disagree with @Iliya Gug. This error cause by setting Project build target to 4.0 (API 14). If change to Java 1.6, you'll can't use Java 1.7 sode style.
For ex: ArrayList myArrayList = new ArrayList<>();. To fix this, set your target to 4.4 (API 19) or higher.