Question

I am trying to save few property into the plist when the user starts the app for the first time, and then I have to retrieve those data and show it to the user, when the user restart the app, so that I don’t have to ask for the same data again.

I am guessing this should be very straight forward, but may be I am missing something.

It would be nice if some one can point me to a sample code for doing the same thing, it would be nice if the code saves and retrieves the data from dictionary to plist and from plist to dictionary.

I looked into the Apple Property List Programming guide and used the code from Reading and Writing Property list data

http://developer.apple.com/library/mac/documentation/Cocoa/Conceptual/PropertyLists/ReadWritePlistData/ReadWritePlistData.html#//apple_ref/doc/uid/10000048i-CH8-SW1

but, when i restart my app, I don’t get back the data that I have stored.

*EDIT*

I am adding some code so that some one can point out if I am making any mistake.

I created a plist file “Data.plist” in my project Resources folder.

This is how I save data in one of my view controller

    NSString *path = [[NSBundle mainBundle] bundlePath];
NSString *finalPath = [path stringByAppendingPathComponent:@"Data.plist"];
//NSString *error;

NSMutableDictionary *dict = [NSMutableDictionary dictionary];


[dict setObject:@"xxxxxx" forKey:@"phoneNumber"];
[dict setObject:@"password" forKey:@"password"];
[dict setObject:@"email" forKey:@"email"];

[dict writeToFile:finalPath atomically:NO];

This is how I am reading the the data on the same view controller viewDidLoad method, because I want to load the data from when next time app starts.

    NSDictionary *dictionary;

// read "Data.plist" from application bundle
NSString *path = [[NSBundle mainBundle] bundlePath];
NSString *finalPath = [path stringByAppendingPathComponent:@"Data.plist"];
dictionary = [NSDictionary dictionaryWithContentsOfFile:finalPath];

// dump the contents of the dictionary to the console
for (id key in dictionary) {
    NSLog(@"bundle: key=%@, value=%@", key, [dictionary objectForKey:key]);
}   

Before saving to the file i can do “po dict” at gdb and can see there are data in the file

NSLog print following error

Assertion failed: (cls), function getName, file /SourceCache/objc4_Sim/objc4-427.1.1/runtime/objc-runtime-new.m, line 3939.

Because when i load data and do “po dictionary” at gdb it is empty

Answer 1

-[NSDictionary writeToFile:atomically:] returns YES or NO depending on whether it’s successful or not. Are you checking the return value?

If I had to take a guess, I’d say it’s because you’re writing the file into the application bundle. You should write it elsewhere in the file system; ~/Library/Application Support/<application name> is the usual location.

Edit:

You can check the return value with something like:

BOOL success = [dict writeToFile:finalPath atomically:YES];
if (!success) {
    NSLog(@"Could not write file");
}