Question

In the .h i’ve declared:

// in database.h
@interface database : UIViewController {
    NSString* databaseName;
    NSString* databasePath;
}

On execution, methodA is called first , which I get the databasePath to point to my database.db file:

//methodA: in database.m
- (void)methodA {
    databaseName = @"database.db";  
    NSArray* documentsPath = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString* documentsDir = [documentsPath objectAtIndex:0];
    databasePath = [documentsDir stringByAppendingPathComponent:databaseName];

    NSFileManager* filemagar = [NSFileManager defaultManager];
    NSString* databasePathFromApp = [[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:databaseName];
    [filemagar copyItemAtPath:databasePathFromApp toPath:databasePath error:nil];

    NSLog (@"databasePath is...%@", databasePath);

[filemagar release];
}

The databasePath will return a string of folder path name “/Users/….”. So this is what I need.

Now subsequently, when I call method B…:

//methodB: in database.m
- (void)methodB {
    NSLog (@"databasePath is now...%@", databasePath);
}

The program terminates as databasePath that is pointing to previous method strings, is no longer the same.

How do I retain the databasePath info , so that I can use in the other methods later?

Answer 1

This line:

databasePath = [documentsDir stringByAppendingPathComponent:databaseName];

Should be:

databasePath = [[documentsDir stringByAppendingPathComponent:databaseName] copy];

Another way to do this would be to use properties:

@interface database : UIViewController {
    NSString* databaseName;
    NSString* databasePath;
}

@property (nonatomic, copy) NSString *databaseName;
@property (nonatomic, copy) NSString* databasePath;

Then in your @implementation:

@synthesize databaseName, databasePath;

- (void) dealloc {
   [self setDatabaseName:nil];
   [self setDatabasePath:nil];
   [super dealloc];
}

//rest of your implementation...