如何将AppDelegate Swift代码放入Objective-C AppDelegate文件并使其工作？

Question

I'm trying to work with an Amazon Web Serivces SDK for iOS called AWSAppSync. I found good instructions for Swift . I'll try to make the question more general to all Obj-c/Swift bridging problems:

There's a code snippet for the AppDelegate.Swift file. However, my AppDelegate is in Objective-C. I've put it into a function (called awsConfig) within a Swift file, referenced the file in the Bridging-Header.h and called the function in the Swift file from my AppDelegate.m:

// AppDelegate.m
#import "<ProductModuleName>-Swift.h"

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    appsyncer *syncClass = [appsyncer new];
    [syncClass awsConfig];

    return YES;
}

And here's the snippet within the Swift file.

// SwiftAppDelegateExtension.Swift 
var appSyncClient: AWSAppSyncClient?

    do {
        // You can choose the directory in which AppSync stores its persistent cache databases
        let cacheConfiguration = try AWSAppSyncCacheConfiguration()

        // AppSync configuration & client initialization
        let appSyncServiceConfig = try AWSAppSyncServiceConfig()
        let appSyncConfig = try AWSAppSyncClientConfiguration(appSyncServiceConfig: appSyncServiceConfig,
                                                              cacheConfiguration: cacheConfiguration)
        appSyncClient = try AWSAppSyncClient(appSyncConfig: appSyncConfig)

    } catch {
        print("Error initializing appsync client. \(error)")
    }

When I want to use it in another Swift file, like this:

let appDelegate = UIApplication.shared.delegate as! AppDelegate
appSyncClient = appDelegate.appSyncClient

I get the error:

(!) Value of type 'AppDelegate' has no member 'appSyncClient'

Why doesn't this work? And what would be a better way to tackle this problem if my workaround is too ugly?

Answer 1

this might be because of the version you currently are working with since this issue can relate to the problem of the versions you are using. So try to use a different version first since this happened to me once and i just used a old version since there are slight changes to the compiler so if you can try different versions and then let me know and make sure to make a report of the versions you tried that failed.

Answer 2

I found the answer to be a slight error: Turns out I put appDelegate.h instead of appDelegate.m in my bridging-header file. After changing that it works. Probably translating the Swift code to objective C would've been a better option, but this is easier if you're not as skilled in both languages like I am.