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POProblem with allocating memory for an Objective-C data object
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copied!<p>I've been programming objective-C for a few months now and have done pretty well so far without having to post any questions. This would be my first. The problem is that I'm getting a memory leak warning from a data object in one of it's methods. I can see that the problem is that I'm sending an alloc to it without releasing it, but I don't know how else to get it to retain the object in memory. If I take the alloc out, the program crashes. If I leave it in, it leaks memory. Here is the method in question:</p> <pre><code>+ (id) featureWithID:(int)fID name:(NSString*)fName secure:(int)fSecure { Feature *newFeature = [[self alloc] init]; newFeature.featureID = fID; newFeature.featureName = fName; newFeature.featureSecure = fSecure; return [newFeature autorelease]; </code></pre> <p>}</p> <p>This method is called by another method in my view controller. This method is as follows:</p> <pre><code>+ (NSMutableArray*) createFeatureArray { NSString *sqlString = @"select id, name, secure from features"; NSString *file = [[NSBundle mainBundle] pathForResource:@"productname" ofType:@"db"]; sqlite3 *database = NULL; NSMutableArray *returnArray = [NSMutableArray array]; if(sqlite3_open([file UTF8String], &database) == SQLITE_OK) { const char *sqlStatement = [sqlString UTF8String]; sqlite3_stmt *compiledStatement; if(sqlite3_prepare_v2(database, sqlStatement, -1, &compiledStatement, NULL) == SQLITE_OK) { while(sqlite3_step(compiledStatement) == SQLITE_ROW) { Feature *myFeature = [Feature featureWithID:sqlite3_column_int(compiledStatement,0) name:[NSString stringWithUTF8String:(char *)sqlite3_column_text(compiledStatement, 1)] secure:sqlite3_column_int(compiledStatement,2)]; [returnArray addObject:myFeature]; } } // Release the compiled statement from memory sqlite3_finalize(compiledStatement); } sqlite3_close(database); return returnArray; </code></pre> <p>}</p> <p>I have tried several things, such as creating a featureWithFeature class method, which would allow me to alloc init the feature in the calling method, but that crashed the program also.</p> <p>Please let me know if you need any clarification or any other parts of the code. Thank you in advance for your help.</p> <p>UPDATE: 4/14/2011</p> <p>After reading the first two responses I implemented the suggestion and found that the program is now crashing. I am at a complete loss as to how to track down the culprit. Hoping this helps, I am posting the calling method from the view controller as well:</p> <pre><code>- (void)setUpNavigationButtons { // get array of features from feature data controller object NSArray *featureArray = [FeatureController createFeatureArray]; int i = 0; for (i = 0; i < [featureArray count]; i++) { Feature *myFeature = [featureArray objectAtIndex:i]; CGRect buttonRect = [self makeFeatureButtonFrame:[featureArray count] withMember:i]; UIButton *aButton = [UIButton buttonWithType:UIButtonTypeRoundedRect]; [aButton setFrame:buttonRect]; [aButton addTarget:self action:@selector(buttonTouched:) forControlEvents:UIControlEventTouchUpInside]; [aButton setTitle:[NSString stringWithFormat:@"%@",myFeature.featureName] forState:UIControlStateNormal]; aButton.tag = myFeature.featureID; [self.view addSubview:aButton]; } </code></pre> <p>}</p> <p>NOTE: These methods are posted in reverse of the order they are invoked. This last method calls the second method, which in turn, calls the first.</p> <p>UPDATE: I've updated these functions to show what is in there now: Below, I will post the header files for the object - maybe that will help</p> <pre><code>@interface Feature : NSObject { int featureID; int featureSecure; NSString *featureName; } @property (nonatomic, assign) int featureID; @property (nonatomic, assign) int featureSecure; @property (nonatomic, retain) NSString *featureName; - (id) init; - (void) dealloc; + (id) featureWithID:(int)fID name:(NSString*)fName secure:(int)fSecure; @end @interface FeatureController : NSObject { } - (id) init; - (void) dealloc; + (NSMutableArray*) createFeatureArray; + (Feature*) getFeatureWithID:(int)fetchID; @end </code></pre>

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