Q:

Saving an object to array using NSMutableDictionary

I have been trying to add an object as an NSMutableDictionary to my array, which I am accessing from another view, and It doesn't seem to work. I want to be able to store the data in a plist which I access from a NSDictionary.
-(void)saveAlarm:(id)sender {

    // Adding object for alarm to AlarmViewController

    alarmArrayCopy = alarmViewController.alarmsTime;

    NSMutableDictionary *newAlarm =  [[NSMutableDictionary alloc] init];
    [newAlarm setValue:labelTextField.text forKey:LABEL_KEY];
    [newAlarm setValue:alarmPicker.date forKey:TIME_KEY];
    [alarmArrayCopy addObject:(newAlarm)];

    // Dismissing and tiding up.

    [self.navigationController dismissModalViewControllerAnimated:YES];
    [newAlarm release];
}

UPDATE: How do I add an NSDictionary to my plist database (my db is an array)?
Here is some new code, I updated the NSMutableDictionary to NSDictionary because in my plist you can only have normal dictionaries not a mutable one. But now it crashed and gives me a Thread 1:Program received signal: "SIGABRT".
NSString *path = [[NSBundle mainBundle] bundlePath];
NSString *finalPath = [path stringByAppendingPathComponent:@"data.plist"];

// Adding object for alarm to AlarmViewController

NSDictionary *newAlarm =  [[NSDictionary alloc] init];
[newAlarm setValue:labelTextField.text forKey:LABEL_KEY];
[newAlarm setValue:[NSString stringWithFormat:@"%@", alarmPicker.date] forKey:TIME_KEY];
[newAlarm writeToFile:finalPath atomically:NO];

or
-(IBAction)saveAlarm:(id)sender {
// Adding object for alarm to AlarmViewController

NSString *time = [NSString stringWithFormat:@"%@", alarmPicker.date];
NSString *label = [NSString stringWithFormat:@"%@",labelTextField.text];

NSDictionary *newAlarm = [[NSDictionary alloc] initWithObjectsAndKeys:label, LABEL_KEY,time, TIME_KEY, nil];
self.alarmArrayCopy = alarmViewController.alarmsTime;
[alarmArrayCopy addObject:(newAlarm)];

// Dismissing and tiding up.
[newAlarm release];
[self.navigationController dismissModalViewControllerAnimated:YES];

}

A:

First, you should use setObject:forKey: method for adding objects to NSMutableDictionary. Second, you should use initWithObjectsAndKeys: method if you are using NSDictionary.
The setValue:forKey is a method of the Key Value Coding protocol. That was described at here “
Where's the difference between setObject:forKey: and setValue:forKey: in NSMutableDictionary?
”
So, you should do that,
NSDictionary *newAlarm = [[NSDictionary alloc] initWithObjectsAndKeys:
                                               labelTextField.text, LABEL_KEY,
                                               alarmPicker.date, TIME_KEY, nil];

