How to change the format of date in date picker

Question

In my iPhone app, I need to display date in yyyy/MM/dd format as show in beloow image

Answer 1

 NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[NSTimeZone resetSystemTimeZone];
NSTimeZone *gmtZone = [NSTimeZone systemTimeZone];
[dateFormatter setTimeZone:gmtZone];
[dateFormatter setDateFormat:@"day, MMM HH:mm:ss Z"];
NSDate *dateT = [dateFormatter dateFromString:str1];
NSString *strDateTaken=[appDelegate convertDate:dateT withFormat:@"EEEE, MMMM dd,yyyy hh:mm a"];
[dateFormatter release];
- (NSString *)convertDate:(NSDate *)date withFormat:(NSString *)format {
    NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
    [formatter setDateFormat:format];
    NSString *dt = [formatter stringFromDate:date];
    [formatter release];
    return dt;
}