Reading values from a plist file - objective-c

Question

I have a UITextField and when the user hits a save button, the text should be saved into a plist file with the following code:
-(IBAction)saveButtonPressed
{
NSError *error;
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); //1
NSString *documentsDirectory = [paths objectAtIndex:0]; //2
NSString *path = [documentsDirectory stringByAppendingPathComponent:#"Data.plist"]; //3
NSFileManager *fileManager = [NSFileManager defaultManager];
if (![fileManager fileExistsAtPath: path]) //4
{
//5
NSString *bundle=[[NSBundle mainBundle] pathForResource:#"Data" ofType:#"plist"];
[fileManager copyItemAtPath:bundle toPath: path error:&error]; //6
}
NSMutableDictionary *data = [[NSMutableDictionary alloc] initWithContentsOfFile: path];
//here add elements to data file and write data to file
[data setObject:[inkTextField text] forKey:#"inkText"];
BOOL didWrite=[data writeToFile: path atomically:YES];
if(didWrite==YES)
NSLog(#"didWrite");
else NSLog(#"nope");
[data release];
}
Then I have a UITableView and I want to load the string value of plist into the cell text field with the following code:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:#"CellViewController"];
if (cell == nil) {
// Load the top-level objects from the custom cell XIB.
NSArray *topLevelObjects = [[NSBundle mainBundle] loadNibNamed:#"CellViewController" owner:self options:nil];
// Grab a pointer to the first object (presumably the custom cell, as that's all the XIB should contain).
cell = [topLevelObjects objectAtIndex:0];
}
NSError *error;
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); //1
NSString *documentsDirectory = [paths objectAtIndex:0]; //2
NSString *path = [documentsDirectory stringByAppendingPathComponent:#"Data.plist"]; //3
NSFileManager *fileManager = [NSFileManager defaultManager];
if (![fileManager fileExistsAtPath: path]) //4
{
//5
NSString *bundle=[[NSBundle mainBundle] pathForResource:#"Data" ofType:#"plist"];
[fileManager copyItemAtPath:bundle toPath: path error:&error]; //6
}
NSMutableDictionary *savedInks = [[NSMutableDictionary alloc] initWithContentsOfFile: path];
//load from savedStock example int value
NSString *value;
value = [[savedInks objectForKey:#"inkText"]stringValue];
[savedInks release];
inkTitle.text=value;
return cell;
}
When I save, I get a the log outputs didWrite, so I know it saved properly. However when I visit the tableView, I get a crash with the following error:
2011-08-19 13:56:45.717 MyApp[36067:b303] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[NSCFString stringValue]: unrecognized selector sent to instance 0x4bb5fa0'
So I thought it was something to do with this line:
value = [[savedInks objectForKey:#"inkText"]stringValue];
so I tried
value = [savedInks objectForKey:#"inkText"];
but that also causes a crash but with no message. What am I doing wrong?

Answer 1

You should remove the 'stringValue', as you're already returning a NSString value.
In the next line, you're releasing 'savedInks', before retaining 'value'. Swap the release with the line below it and see if that works.:
NSString *value;
value = [savedInks objectForKey:#"inkText"];
inkTitle.text=value;
[savedInks release];
When savedInks is released, all of the objects within the dictionary are released as well. Setting inkTtile.text should perform a retain on value automatically.