Xcode中Link Binary With Libraries

Xcode中Link Binary With Libraries Status Required or Optional

Libraries and frameworks are designated as Required by default, but you can change this designation to Optional. Required libraries must be present on the host computer for the product to load. Optional libraries do not have to be present for the product to load. A Required framework will always be loaded into memory, but an Optional framework will be loaded only if needed. The initial load of the application will be faster if a large library that is never needed is designated as Optional.

内容:在指定设备上根据系统版本选择加载framework 状态,否则会出现崩溃.常见 <NotficationCenter.framework>需要 Optional,否则会在低版本系统ios7下崩溃.