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Fatal error: unexpectedly found nil while unwrapping an Optional values [duplicate]
...r: String!) -> AnyObject! // Used by the delegate to acquire an already allocated cell, in lieu of allocating a new one.
That's determined by the exclamation mark after AnyObject:
AnyObject!
So, first thing to consider is, what is an "Implicitly Unwrapped Optional"?
The Swift Programmin...
Static variables in member functions
...ted meanings in C++
When used for data members it means that the data is allocated in the class and not in instances.
When used for data inside a function it means that the data is allocated statically, initialized the first time the block is entered and lasts until the program quits. Also the var...
Eclipse error: 'Failed to create the Java Virtual Machine'
...retty old now but I have just had the same issue and the problem was I was allocating to much memory to eclipse that it could not get hold of. So open eclipse.ini and lower the amount of memory that is being allocated to -Xmx XXMaxPermSize I changed mine to -Xmx512m and XXMaxPermSize256m
...
Long press on UITableView
...view:
UILongPressGestureRecognizer *lpgr = [[UILongPressGestureRecognizer alloc]
initWithTarget:self action:@selector(handleLongPress:)];
lpgr.minimumPressDuration = 2.0; //seconds
lpgr.delegate = self;
[self.myTableView addGestureRecognizer:lpgr];
[lpgr release];
Then in the gesture handler:
...
Are the days of passing const std::string & as a parameter over?
...ith `str`.
m_str = str;
}
Hello, copy constructor and potential memory allocation (ignore the Short String Optimization (SSO)). C++11's move semantics are supposed to make it possible to remove needless copy-constructing, right? And A passes a temporary; there's no reason why C should have to co...
How to populate/instantiate a C# array with a single value?
...ence, so it has to guess as to the array size. That means you'll get array allocations every time ToArray's buffer is exceeded, plus one more allocation at the end for the trim. There's also overhead involved with the enumerable object.
– Edward Brey
Feb 12 '16...
What is the best way to deal with the NSDateFormatter locale “feechur”?
...self init];
if (en_US_POSIX == nil) {
en_US_POSIX = [[NSLocale alloc] initWithLocaleIdentifier:@"en_US_POSIX"];
}
[self setLocale:en_US_POSIX];
return self;
}
@end
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Objective-C declared @property attributes (nonatomic, copy, strong, weak)
...red when the attribute is a pointer to a reference counted object that was allocated on the heap. Allocation should look something like:
NSObject* obj = [[NSObject alloc] init]; // ref counted var
The setter generated by @synthesize will add a reference count to the object when it is copied so the ...
How to compare two NSDates: Which is more recent?
...
NSDate *retVal;
NSDateComponents *components = [[NSDateComponents alloc] init];
[components setDay:days];
NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
retVal = [gregorian dateByAddingComponents:components toDate:self options:0];
...
Are delphi variables initialized with a value by default?
...
Global variables that don't have an explicit initializer are allocated in the BSS section in the executable. They don't actually take up any space in the EXE; the BSS section is a special section that the OS allocates and clears to zero. On other operating systems, there are similar me...