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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 ...
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...
How can a string be initialized using “ ”?
...age for strings with the same contents to conserve storage. String objects allocated via new operator are stored in the heap, and there is no sharing of storage for the same contents.
...
Check if a string contains a string in C++
... which is expensive, particularly for longer strings that necessitate heap allocations. Further, say you call CheckSubstring("XYZab", "ab\0\0") - the while loop will end up comparing a to a, b to b, the implicit NUL at the end of the first string to the explicit NUL in the second, then it will read...
Dynamically changing font size of UILabel
...loat)i];
NSAttributedString *attributedText = [[NSAttributedString alloc] initWithString:text attributes:@{NSFontAttributeName: font}];
CGRect rectSize = [attributedText boundingRectWithSize:CGSizeMake(self.frame.size.width, CGFLOAT_MAX) options:NSStringDrawingUsesLineFragmentOrigin...
How to hide UINavigationBar 1px bottom line
...earance proxy:
[[UINavigationBar appearance] setBackgroundImage:[[UIImage alloc] init]
forBarPosition:UIBarPositionAny
barMetrics:UIBarMetricsDefault];
[[UINavigationBar appearance] setShadowImage:[[UIImage alloc] init]];
...
Sort NSArray of date strings or objects
...escriptor as below:
NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"beginDate" ascending:TRUE];
[myMutableArray sortUsingDescriptors:[NSArray arrayWithObject:sortDescriptor]];
[sortDescriptor release];
...
iOS 7 status bar back to iOS 6 default style in iPhone app?
...egate.h to make background a property in your class and prevent ARC from deallocating it. (You don't have to do it if you are not using ARC.)
After that you just need to create the UIWindow in if (NSFoundationVersionNumber > NSFoundationVersionNumber_iOS_6_1):
background = [[UIWindow alloc] ini...
How can I initialize base class member variables in derived class constructor?
...onstructor. It will first be default-initialized when the instance of B is allocated, then it will be assigned inside the B's constructor. But I also think the compiler can still optimize this.
– Violet Giraffe
Jan 10 '19 at 11:36
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C++, copy set to vector
...This doesn't deserve -1. In particular, this allows vector to only do one allocation (since it can't determine the distance of set iterators in O(1)), and, if it wasn't defined for vector to zero out each element when constructed, this could be worthwhile to allow the copy to boil down to a memcpy...