Apple Mach-O Linker (Id) 可达性错误

Question

I keep getting this error when I try to build my project which uses reachability (the error only came up after I tried to implement reachability):

I read some other posts on the inte.net but nothing seemed to work. I added SystemConfiguration.framework (project, build phases, +), but that didn't work (I had already added it when the error came up). Here's how I implement the files:

#import <UIKit/UIKit.h>
#import "Reachability.h"

@interface catalogDetailView : UIViewController{

}

-(void)checkNetwork;

@end

Then in the.m:

#import "catalogDetailView.h"
-(void)checkNetwork{
    if ([self reachable]) {
        NSLog(@"Connected to Network");
    }
    else {
        NSLog(@"Connection Failed");
    }
}
-(BOOL)reachable {
    Reachability *r = [Reachability reachabilityWithHostName:@"apple.com"];
    NetworkStatus internetStatus = [r currentReachabilityStatus];
    if(internetStatus == NotReachable) {
        return NO;
    }
    return YES;
}

So if you could help that would be amazing;! Thanks ;) Luke

Answer 1

You need to add Reachability.m to your target's "Compile Sources" build phase.

One way to do it:

1. Select Reachability.m in the project navigator, on the left side of the Xcode window. If you don't see it, choose the menu View > Navigators > Show Project Navigator.
2. Show the file inspector on the right side of the Xcode window. View > Utilities > Show File Inspector.
3. In the Target Membership section, check the checkbox next to your target.

Answer 2

I'll bet you that your 'compile sources list' does not contain reachability.m . Drag it in under the build phases tab to the list. I often find that when adding files to a project, Xcode often doesn't add the files your target's compile list (because the default is to not add them).