My function can not access self property since code is centralised [closed] - ios

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I am fairly new at using xCode, so sorry if this question seems strange.
In my app I would like all the views and tableviews to channel their DB (sqlite3) access trough one object. I already got the openDatabase function running but seem to have an issue with the function that creates a new one when none is available.
It all used to work when the code was in the view itself, but centralising it made it a lot more difficult than I had anticipated :(.
below my code for the .h and .m:
beDbAccess.h
//
// beDbAccess.h
// myDiveApp
//
// Created by Jurgen on 07/09/13.
// Copyright (c) 2013 Dictus. All rights reserved.
//
#import "beObject.h"
#import "sqlite3.h"
#interface beDbAccess : NSObject
{
NSArray *path;
NSString *docPath;
NSString *dbPathString;
NSFileManager *fileManager;
}
#property (nonatomic, retain) NSArray *path;
#property (nonatomic) NSString *docPath;
#property (nonatomic) NSString *dbPathString;
#property (nonatomic) NSFileManager *fileManager;
#pragma functions callable from the outside
NSString *openDatabase();
#pragma functions
-(void)createNewDatabase;
#end
=================
beDbAccess.m
//
// beDbAccess.m
// myDiveApp
//
// Created by Lion on 07/09/13.
// Copyright (c) 2013 Dictus. All rights reserved.
//
// LET EROP DAT JE NOOIT '' gebruikt rond de veldnamen in de WHERE CLAUSE !!!
#import "beDbAccess.h"
#implementation beDbAccess
#synthesize path, dbPathString, docPath, fileManager;
NSMutableArray *arrayOfButtons;
sqlite3 *myDb;
NSArray *path;
NSFileManager *fileManager;
NSString *docPath, *dbPathString;
UIRefreshControl *refreshControl;
NSString *openDatabase()
{
sqlite3 *myDb;
NSArray *path = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *docPath = [path objectAtIndex:0];
NSString *dbPathString = [docPath stringByAppendingPathComponent:#"myDb.db"];
NSFileManager *fileManager = [NSFileManager defaultManager];
if (![fileManager fileExistsAtPath:dbPathString])
{
const char *dbPath = [dbPathString UTF8String];
if (sqlite3_open(dbPath, &myDb)==SQLITE_OK)
{
NSLog(#" Create Database: EMPTY ...");
/*!*/ [self createNewDatabase]; // This is where the problem lies... Use of undeclared identifier 'self' :(
} else NSLog(#"#Local: db open...");
}
return dbPathString;
}

Answer 1

Functions are not methods conceptually
Functions don't know about a self pointer because they typically don't belong to a class
In your case you have to make the function part of the class OR give it access to the class some other way (which wouldn't be OO style)
e.g.
#interface beDbAccess : NSObject
{
NSArray *path;
NSString *docPath;
NSString *dbPathString;
NSFileManager *fileManager;
}
#property (nonatomic, retain) NSArray *path;
#property (nonatomic) NSString *docPath;
#property (nonatomic) NSString *dbPathString;
#property (nonatomic) NSFileManager *fileManager;
#pragma functions callable from the outside
+ (id)sharedInstance;
-(NSString*)openDatabase;
#pragma functions
-(void)createNewDatabase;
#end
THEN use it from the outside like:
[[beDbAccess sharedInstance] openDatabase];