I faced this error during generating apk using idea13
ProGuard: Warning: butterknife.internal.InjectViewProcessor: can\'t find superclass or interface javax.ann
Even though you didn't post an actual question, I'm assuming you want that warning gone.
Add the following lines to your ProGuard configuration:
-dontwarn butterknife.internal.** -keep class **$$ViewInjector { *; } -keepnames class * { @butterknife.InjectView *;}
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