'CLLocationManager'没有可见的@interface声明选择器'requestAlwaysAuthorization'

Question

我们正在制作一个与iOS 8兼容的应用程序,但与此同时,我们的一些开发人员还没有Xcode 6,因此他们在尝试调用时遇到此错误

[self.locationManager requestAlwaysAuthorization];

即使它在if里面

if(floor(NSFoundationVersionNumber) > NSFoundationVersionNumber_iOS_7_1) {
    [self.locationManager requestAlwaysAuthorization];
}

我们怎么解决这个问题才能在Xcode 5上编译？

Answer 1

以下是处理此问题的正确方法.这假定您的应用程序具有iOS 7.x或更早版本的"部署目标",您需要使用"Base SDK"的不同值编译项目(例如Xcode 6下的iOS 8和Xcode 5下的iOS 7):

#if __IPHONE_OS_VERSION_MAX_ALLOWED >= 80000
    // Being compiled with a Base SDK of iOS 8 or later
    // Now do a runtime check to be sure the method is supported
    if ([self.locationManager respondsToSelector:@selector(requestAlwaysAuthorization)]) {
        [self.locationManager requestAlwaysAuthorization];
    } else {
        // No such method on this device - do something else as needed
    }
#else
    // Being compiled with a Base SDK of iOS 7.x or earlier
    // No such method - do something else as needed
#endif