[mutableTitles addObject:@"New App title"];

//
//  FilesHandlingViewController.m
//  FilesHandling
//
//  Created by Martin Chrobot on 25/04/2011.
//  Copyright 2011 home. All rights reserved.
//

#import "FilesHandlingViewController.h"

@implementation FilesHandlingViewController

//finds the path to the application's documents directory
-(NSString *)documentsPath {
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *documentsDir = [paths objectAtIndex:0];
    return documentsDir;
}

//write content into a specified file path
-(void)writeToFile:(NSString *)text withFileName:(NSString *)filePath {
    NSMutableArray *array = [[NSMutableArray alloc] init];
    [array addObject:text];
    [array writeToFile:filePath atomically:YES];
    [array release];
}

//read content from a specified file path
-(NSString *)readFromFile:(NSString *)filePath {
    //check if file exists
    if([[NSFileManager defaultManager] fileExistsAtPath:filePath]){
        NSArray *array = [[NSArray alloc] initWithContentsOfFile:filePath];
        NSString *data = [NSString stringWithFormat:@"%@", [array objectAtIndex:0]];
        
        [array release];
        return data;
    } else {
        return nil;
    }
}

- (void)dealloc
{
    [super dealloc];
}

- (void)didReceiveMemoryWarning
{
    // Releases the view if it doesn't have a superview.
    [super didReceiveMemoryWarning];
    
    // Release any cached data, images, etc that aren't in use.
}

#pragma mark - View lifecycle


// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.
- (void)viewDidLoad
{
    //formulate filename
    NSString *fileName = [[self documentsPath] stringByAppendingPathComponent:@"data.txt"];
    
    //write something to the file
    [self writeToFile:@"a string of text" withFileName:fileName];
    
    //read it back
    NSString *fileContent = [self readFromFile:fileName];
    
    //display the content read in the debugger console window
    NSLog(@"%@", fileContent);
    
    //get the path to the property list file
    NSString *plistFileName = [[self documentsPath] stringByAppendingPathComponent:@"Apps.plist"];
    
    //if the property list can be found
    if([[NSFileManager defaultManager]fileExistsAtPath:plistFileName]){
        //load the content of the property list file into a NSDictionary object
        NSDictionary *dict = [[NSDictionary alloc] initWithContentsOfFile:plistFileName];
        
        //for each category
        for(NSString *category in dict){
            NSLog(@"%@", category);
            NSLog(@"========");
            
            //return all titles in an array
            NSArray *titles = [dict valueForKey:category];
            
            //print out all the titles in that category
            for(NSString *title in titles){
                NSLog(@"%@", title);
            }
        }
        [dict release];
    } else {
        //load the property list from the resource folder
        NSString *pListPath = [[NSBundle mainBundle] pathForResource:@"Apps" ofType:@"plist"];
        NSDictionary *dict = [[NSDictionary alloc] initWithContentsOfFile:pListPath];
        
        //make mutable copy of the dictionary object
        NSMutableDictionary *copyOfDict = [dict mutableCopy];
        
        //get all the different categories
        NSArray *categoriesArray = [[copyOfDict allKeys] sortedArrayUsingSelector:@selector(compare:)];
        
        //for each category
        for(NSString *category in categoriesArray){
            //get all the app titles in that category
            NSArray *titles = [dict valueForKey:category];
            
            //make a mutable copy of the array
            NSMutableArray *mutableTitles = [titles mutableCopy];
            
            //add new title to the category
            [mutableTitles addObject:@"New App title"];
            
            //set the array back to the dictionary object
            [copyOfDict setObject:mutableTitles forKey:category];
            [mutableTitles release];
        }
        
        //write the dictionary to file
        fileName = [[self documentsPath]stringByAppendingPathComponent:@"Apps.plist"];
        [copyOfDict writeToFile:fileName atomically:YES];
        [dict release];
        [copyOfDict release];
    }
    
    [super viewDidLoad];
}


- (void)viewDidUnload
{
    [super viewDidUnload];
    // Release any retained subviews of the main view.
    // e.g. self.myOutlet = nil;
}

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
    // Return YES for supported orientations
    return (interfaceOrientation == UIInterfaceOrientationPortrait);
}

@end

} else {
        //load the property list from the resource folder
        NSString *pListPath = [[NSBundle mainBundle] pathForResource:@"Apps" ofType:@"plist"];
        NSDictionary *dict = [[NSDictionary alloc] initWithContentsOfFile:pListPath];
		
        
        //make mutable copy of the dictionary object
        NSMutableDictionary *copyOfDict = [dict mutableCopy];
        
        //get all the different categories
        NSArray *categoriesArray = [[copyOfDict allKeys] sortedArrayUsingSelector:@selector(compare:)];
		NSLog(@"The keys are %@",categoriesArray); // the list of keys in the root dictionary. With the current plist the only key is "Root", not the 3 array keys that were expected
        
        //for each category
        for(NSString *category in categoriesArray){
			NSLog(@"The category is %@",category); // The key to be checked - again with the plist list error the only key is "Root"
            //get all the app titles in that category
            NSArray *titles = [dict valueForKey:category]; 
			NSLog(@"titles is %@",titles); // the object at the key lists its contents 
NSLog(@"titles is a %@", [titles class]); // You see that titles is not an array but __NSCFDictionary
            
            //make a mutable copy of the array
            NSMutableArray *mutableTitles = [titles mutableCopy];
            
            //add new title to the category
            [mutableTitles addObject:@"New App title"];
            
            //set the array back to the dictionary object
            [copyOfDict setObject:mutableTitles forKey:category];
            [mutableTitles release];
        }