How to read data structure from .plist file into NSArray

Question

I was creating a data structure manually using the following:

NSDictionary* league1 = [[NSDictionary alloc] initWithObjectsAndKeys: @"Barclays Premier League", @"name",
        @"Premier League", @"shortname",
        @"101", @"id", nil];
NSDictionary* league2 = [[NSDictionary alloc] initWithObjectsAndKeys: @"Coca-Cola Championship", @"name",
        @"Championship", @"shortname",
        @"102", @"id", nil];
NSDictionary* league3 = [[NSDictionary alloc] initWithObjectsAndKeys: @"Scottish Premier League", @"name",
        @"SPL", @"shortname",
        @"201", @"id", nil];
NSDictionary* league4 = [[NSDictionary alloc] initWithObjectsAndKeys: @"Champions League", @"name",
        @"UCL", @"shortname",
        @"501", @"id", nil];

contentArray = [[NSArray alloc] initWithObjects:

       [[NSDictionary alloc] initWithObjectsAndKeys: @"English", @"category", [[NSArray alloc] initWithObjects: league1, league2, nil], @"leagues", nil],
       [[NSDictionary alloc] initWithObjectsAndKeys: @"Scottish", @"category", [[NSArray alloc] initWithObjects: league3, nil], @"leagues", nil],
       [[NSDictionary alloc] initWithObjectsAndKeys: @"Tournaments", @"category", [[NSArray alloc] initWithObjects: league4, nil], @"leagues", nil],
       nil];

[league1 release];
[league2 release];
[league3 release];
[league4 release];

However, I thought this would be better if it was read from a file. So I created the file leagues.plist which has the following structure:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd"&gt;
<plist version="1.0">
    <array>
     <dict>
      <key>category</key>
      <string>English</string>
      <key>leagues</key>
      <array>
       <dict>
        <key>name</key>
        <string>Barclays Premier League</string>
        <key>shortname</key>
        <string>Premier League</string>
        <key>id</key>
        <string>101</string>
       </dict>
       <dict>
        <key>name</key>
        <string>Coca-Cola Championship</string>
        <key>shortname</key>
        <string>Championship</string>
        <key>id</key>
        <string>102</string>
       </dict>
      </array>
     </dict>
     <dict>
      <key>category</key>
      <string>Scottish</string>
      <key>leagues</key>
      <array>
       <dict>
        <key>name</key>
        <string>Scottish Premier League</string>
        <key>shortname</key>
        <string>SPL</string>
        <key>id</key>
        <string>201</string>
       </dict>
      </array>
     </dict>
     <dict>
      <key>category</key>
      <string>Tournaments</string>
      <key>leagues</key>
      <array>
       <dict>
        <key>name</key>
        <string>Champions League</string>
        <key>shortname</key>
        <string>UCL</string>
        <key>id</key>
        <string>501</string>
       </dict>
      </array>
     </dict>
    </array>
</plist>

How do I read this file in. I have tried various methods but nothing has worked. I don't even know if I am looking in the right place for the file. For reference I am trying the following methods:

NSString* errorDesc = nil;
NSPropertyListFormat format;
NSString* plistPath = [[NSBundle mainBundle] pathForResource:@"league" ofType:@"plist"];
NSData* plistXML = [[NSFileManager defaultManager] contentsAtPath:plistPath];
contentArray = (NSArray*)[NSPropertyListSerialization
             propertyListFromData:plistXML
             mutabilityOption:NSPropertyListMutableContainersAndLeaves
             format:&format
             errorDescription:&errorDesc];

if (!contentArray) {
    NSLog(errorDesc);
    [errorDesc release];
}

or

NSString* plistPath = [[NSBundle mainBundle] pathForResource:@"league" ofType:@"plist"];
contentArray = [NSArray arrayWithContentsOfFile:plistPath];

or

NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,NSUserDomainMask, YES);
NSString *documentsPath = [paths objectAtIndex:0];

NSString *fooPath = [documentsPath stringByAppendingPathComponent:@"leagues.plist"];
NSLog(fooPath);
contentArray = [NSArray arrayWithContentsOfFile:fooPath];
NSLog(@"%@",contentArray);

This is finally driving me completely insane. Help please!

Thank you kindly

Answer 1

NSString* plistPath = [[NSBundle mainBundle] pathForResource:@"league" ofType:@"plist"];
contentArray = [NSArray arrayWithContentsOfFile:plistPath];

That answer is correct - are you sure that your file is in the app? Did you add it to your project, and check to see if it gets copied into your app bundle?

Answer 2

Kendall is correct.

In my experience, you need to add your file to the "Resources" folder in xcode.

Answer 3

For completeness, Kendall and bentford are completely correct. However, in my sample, contentArray was a property and by the end of the method it was going out of scope because arrayWithContentsOfFile creates an auto-released object.

To make this work correctly I needed to do 3 things:

1. put the file in the resources folder

2. name the file correctly (was leagues.plist instead of league.plist)

3. read the file using [[NSArray alloc] initWithContentsOfFile:plistPath);

the third part creates an allocated NSArray that does not release when you exit the scope of this function... of course, this needed to be released in the dealloc function.

Answer 4

i am trying to write multiple arrays into same plist but the i am not able retain the previous data in the plist it is getting replaced......can you send me the code to change the cursor position in an plist file

Answer 5

Just to add. I had the same problem and the suggested solution helped me solve the problem, however I am not sure if I actually used the exact solution. In my case the problem was that the .plist file was added to a different target (had added a new target a moment before). Therefore the solution was .plist > Get Info > Targets, and make sure it is added to the correct target so it gets copied to device when installing. Darn had I figure that out soon enough I would have saved a lot of time. Hope this is helpful too. Regards!