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POWhy is NSPredicate evaluateWithObject nil when searching for string within NSMutableArray loaded from plist
 

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  1. POWhy is NSPredicate evaluateWithObject nil when searching for string within NSMutableArray loaded from plist
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    <p>I am trying to check within a plist if I had previously saved the value (song) before. Basically why is this:</p> <pre><code> if ([condition evaluateWithObject:favoritesArray] == YES) { return; } </code></pre> <p>being evaluated to nil while this:</p> <pre><code>if ([[favoritesArray filteredArrayUsingPredicate:condition] count] != 0) { return; } </code></pre> <p>works perfectly fine with the exact same condition. </p> <p>Sample of plist:</p> <pre><code>( { artist = Yuna; image = ""; isFavorite = 1; song = "I Wanna Go (BELARBI REMIX)"; thumbnail = "http://userserve-ak.last.fm/serve/64/94177627.png"; } ) </code></pre> <p>printed condition: </p> <pre><code>song = "I Wanna Go (BELARBI REMIX)" </code></pre> <p>Note: changing condition to "song LIKE %@" gives me an "Can't do regex matching on object" error. "song.song" is a NSString.</p> <p>Here is the full code below:</p> <pre><code>- (void) saveFavorite: (Songs*)song { NSMutableArray *favoritesArray = [NSMutableArray arrayWithContentsOfFile:[MBCUtils dataFilePathWithFile:@"favorites.plist"]]; NSPredicate *condition = [NSPredicate predicateWithFormat:@"song == %@" argumentArray:@[song.song]]; if (favoritesArray == nil) { favoritesArray = [NSMutableArray arrayWithCapacity:1]; } else { //favorite is already in list; NSLog(@"filtered favs: %@", [favoritesArray filteredArrayUsingPredicate:condition]); if ([[favoritesArray filteredArrayUsingPredicate:condition] count] != 0) { return; } // why this isn't working is beyond me; if ([condition evaluateWithObject:favoritesArray] == YES) { return; } } [favoritesArray addObject:[song toDictionary]]; [favoritesArray writeToFile:[MBCUtils dataFilePathWithFile:@"favorites.plist"] atomically:YES]; } </code></pre>
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    1. USMircea Botez
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