Navigation Controller Data Store Help

[DenVog]

I am working on a Navigation controller that will allow users to select from different media. I have a basic text-based controller working (top image), but am running into issues as I start to add detail to it (mock-up bottom image). The most pressing question which is, how should I store the data?

Things to keep in mind are:

• List of albums will always be short (i.e. less than 10) and static
• Display correct thumbnail image of album art in each row of Albums table
• Same but larger image of album art in detail view of selected album
• Text field that can hold a couple paragraphs of information in detail view of selected album

I've seen data stored in a number of ways:
Array within my AlbumsController.m file, plist file, Dictionary, SQL database

I like the array approach, as it is really convenient to implement, but doesn't seem to allow for:

• different image in each row
• second line of text (i.e. album date under album name in table row cell)
• place to store a couple of paragraphs of text that will only be shown on the detail screen

Here's what I use now:

- (void)viewDidLoad {
	NSArray *array = [[NSArray alloc] initWithObjects:@"Album 1", @"Album 2", @"Album 3", nil];
	self.list = array;
	[array release];
	[super viewDidLoad];
}

I'd really like to be able to create a single AlbumsDetail.xib file as a template and just have the appropriate information populate the fields based on which album was selected from the Albums table.

Current

Goal

Thank you for any guidance. I have been through the Apple sample code (e.g. TheElements), a couple books, and the threads here. The approaches all have slightly different implications, and I'm having trouble reconciling them...

[rooster117]

Hello,

I guess the question I have for you is whether you want the user to be able to add, edit or change the data in any way?

If the answer is no: If you aren't gonna have too much data then you can just stick with the array approach. You can even hard code it.

I like the array approach, as it is really convenient to implement, but doesn't seem to allow for:

* different image in each row
* second line of text (i.e. album date under album name in table row cell)
* place to store a couple of paragraphs of text that will only be shown on the detail screen

You can do this with arrays but not just one. To make it simple for your case you could just do three arrays that are all the same size. so:

NSArray *title_array = .....
NSArray *details_array = .....
NSArray *image_array = .....

Just make sure the first element in title_array is intended for details_array and image_array so that when you're setting up your cell for the table view you would set your title to: [title_array objectAtIndex:indexpath.row]; and your image to: [image_array objectAtIndex:indexpath.row];

Then in your details view you would pass in the details_array element at the same index.

Let me know if you have any other questions regarding that.

Otherwise if you do need to edit it I would suggest sql which is another animal.

In terms of your views and view controllers. If you only want to have one .xib then make a tableviewnavigationcontroller (or however its spelled) and added a details view to it. For the first two levels in your image you will need to build the tableview with the delegate methods. If this is all in one controller and using arrays you will have to have all of the array information hard coded in and you will have to keep track of what level you are in and what item has been selected(if you are in the second level). You can store this in the app delegate pretty easily.

Sorry if my reply is long. Let me know if there is something you need more clarification on.

Thanks
-Ryan

Bolt and Nut iphone utility app
Tooth Brush Timer

[DenVog]

Hi Ryan. Thanks for your detailed reply.

Originally Posted by rooster117

I guess the question I have for you is whether you want the user to be able to add, edit or change the data in any way?

I don't need the user to do anything other than view the data that I provide.

I've made some decent progress thanks to your message, and a tutorial I found. I am a little stuck now, trying to get my albumYear label to display info from an array. The albumTitle label displays fine. The albumYear label will display the same value in all rows if I hard code it

albumYearValue.text = @"Sub Value";

When I use the following code to try to get the albumYear label to display a different value in each row based on data from an array, it's just blank.

- (void)viewDidLoad {
	 [super viewDidLoad];
	 
	 //Initialize the array
	 albumsArray = [[NSMutableArray alloc] init];
	 
	 NSArray *albumTitleArray = [NSArray arrayWithObjects:@"Album 1", @"Album 2", @"Album 3", nil];
	 NSDictionary *albumTitleDic = [NSDictionary dictionaryWithObject:albumTitleArray forKey:@"Title"];
	 
	 NSArray *albumYearArray = [NSArray arrayWithObjects:@"1995", @"2000", @"2005", nil];
	 NSDictionary *albumYearDic = [NSDictionary dictionaryWithObject:albumYearArray forKey:@"Year"];
	 
	 [albumsArray addObject:albumTitleDic];
	 [albumsArray addObject:albumYearDic];

	 copyListOfItems = [[NSMutableArray alloc] init];
	 
} 

#pragma mark -
#pragma mark Table Data Source Methods
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
	//Number of rows it should expect should be based on the section
	NSDictionary *dictionary = [albumsArray objectAtIndex:section];
	NSArray *array = [dictionary objectForKey:@"Title"];
	return [array count];

}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
    static NSString *CellIdentifier = @"Cell";
	
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
	if (cell == nil)
		cell = [self getCellContentView:CellIdentifier];
	UILabel *albumTitleValue = (UILabel *)[cell viewWithTag:kAlbumTitleValueTag];
	UILabel *albumYearValue = (UILabel *)[cell viewWithTag:kAlbumYearValueTag];

	NSDictionary *dictionary = [albumsArray objectAtIndex:indexPath.section];
	
	NSArray *titleArray = [dictionary objectForKey:@"Title"];
	NSString *titleValue = [titleArray objectAtIndex:indexPath.row];
	albumTitleValue.text = titleValue;
	[titleValue release];

	NSArray *yearArray = [dictionary objectForKey:@"Year"];
	NSString *yearValue = [yearArray objectAtIndex:indexPath.row];
	albumYearValue.text = yearValue;
	[yearValue release];
	return cell;
}

- (UITableViewCell *) getCellContentView:(NSString *)cellIdentifier {
	
	CGRect cellFrame = CGRectMake(0, 0, 300, 65);
	CGRect albumTitleValueRect = CGRectMake(80, 5, 200, 15);
	CGRect albumYearValueRect = CGRectMake(80, 25, 200, 15);
	UILabel *titleTemp;
	UILabel *yearTemp;
	UITableViewCell *cell = [[[UITableViewCell alloc] initWithFrame:cellFrame reuseIdentifier:cellIdentifier] autorelease];
	
	
	//Initialize Label with AlbumTitle Tag
	titleTemp = [[UILabel alloc] initWithFrame:albumTitleValueRect];
	titleTemp.tag = kAlbumTitleValueTag;
	[cell.contentView addSubview:titleTemp];
	[titleTemp release];
	
	//Initialize Label with AblumYear Tag
	yearTemp = [[UILabel alloc] initWithFrame:albumYearValueRect];
	yearTemp.tag = kAlbumYearValueTag;
	yearTemp.font = [UIFont boldSystemFontOfSize:12];
	yearTemp.textColor = [UIColor lightGrayColor];
	[cell.contentView addSubview:yearTemp];
	[yearTemp release];
	
	return cell;
}

Thanks again for your assistance.

[rooster117]

To be honest I've yet to use dictionary stuff. If you can hard code what you want then the problem has to be in the data structure. If I were you I'd use the debugger at this point and step through the code to see if the array contains what you want and when you want it.

Could be something simple.

Sorry if this response isn't as helpful

-Ryan

[DenVog]

Originally Posted by rooster117

To be honest I've yet to use dictionary stuff

I am not set on using dictionary. Just an example I found that I was able to get working. If there is an easier way, please do share.

Originally Posted by rooster117

If you can hard code what you want then the problem has to be in the data structure. If I were you I'd use the debugger at this point and step through the code to see if the array contains what you want and when you want it.

Could be something simple.

You are probably right. I spent a couple hours troubleshooting this evening, and can't seem to find it. Maybe a fresh look at it tomorrow will help.

[rooster117]

For me I would just make a second array for the album year and keep them in synch. So each index of one corresponds to the same index of the other. Then you could just use the same "indexPath.row" to access them both. This probably breaks some coding standards but it would be easy to get working and you could always change methods once you get the basics down.

I personally find most of my problems like this with the inline debugger. Good luck.

-Ryan