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POshort call for singleton
 

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    <p><strong>Update with working code. Problem was like @HotLinks state, that I did <code>init</code> instead of <code>initWithBaseURL:url</code></strong></p> <p>I am using a <code>Singleton</code> in my App, based on <a href="http://www.johnwordsworth.com/2010/04/iphone-code-snippet-the-singleton-pattern/" rel="nofollow">this guide</a>. </p> <p>Now every time I use the singleton I do like this: </p> <pre><code>SingletonClass* sharedSingleton = [SingletonClass sharedInstance]; [sharedSingleton callAMethod]; // or [[SingletonClass sharedInstance] callAMethod]; </code></pre> <p><strong>Is there a way to use a short syntax, especially if I have to use the <code>Singleton</code> several times?</strong> Something like: </p> <pre><code>[sc callAMethod]; </code></pre> <p>I tried already this kind, but it did not work, as the init method was not called... </p> <h3>WebApi.h</h3> <pre class="lang-c prettyprint-override"><code>#import "AFHTTPRequestOperationManager.h" #import "SingletonClass.h" @interface WebApi : AFHTTPRequestOperationManager @property (nonatomic, strong) SingletonClass *sc; +(WebApi*)sharedInstance; -(void)sandbox; @end </code></pre> <h3>WebApi.m (updated with working code)</h3> <pre class="lang-c prettyprint-override"><code>#import "WebApi.h" @implementation WebApi //-(WebApi*)init { -(WebApi*)initWithBaseURL:url { self = [super init]; if (self != nil) { self.sc = [SingletonClass sharedInstance]; // is never called. } return self; } #pragma mark - Singleton methods /** * Singleton methods */ +(WebApi*)sharedInstance { static WebApi *sharedInstance = nil; static dispatch_once_t oncePredicate; dispatch_once(&amp;oncePredicate, ^{ sharedInstance = [[self alloc] initWithBaseURL:[NSURL URLWithString:kApiHost]]; }); return sharedInstance; } -(void)sandbox { DLog(@"test short singleton call: %@", [sc callAMethod]; } @end </code></pre> <h3>Debug Message</h3> <blockquote> <p>[WebApi sandbox] [Line 42] test short singleton call: (null)</p> </blockquote>
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    1. COYou can certainly create a "class" ("+") method of your singleton class that obtains the singleton pointer and then cascades to the instance method.
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    2. COWhat about just: `#define SC [SingletonClass sharedInstance]`
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    3. CO@HotLicks I often have recognized that init methods where not called - at least breakpoints where never hit, that where placed on the init method. It was always strange to me, but I could never figure out why. Yes I am calling it in another Singleton class.
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