我想製作一個滑塊來控制設備的音量。 以前我曾與MPVolumeView做到了這一點,但因爲iOS 5中我得到生成以下錯誤: Undefined symbols for architecture armv7:
"_OBJC_CLASS_$_MPVolumeView", referenced from:
objc-class-ref in PlayerViewController.o
l
Xcode中給我的錯誤編譯: Undefined symbols for architecture i386:
"_OBJC_CLASS_$_MPVolumeView", referenced from:
objc-class-ref in VolumeViewController.o
ld: symbol(s) not found for architecture