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UIActivityViewController crashing on iOS 8 iPads
...image];
UIActivityViewController *controller = [[UIActivityViewController alloc] initWithActivityItems:postItems applicationActivities:nil];
//if iPhone
if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPhone) {
[self presentViewController:controller animated:YES completion:nil];
}
//if iPa...
What is the difference between native code, machine code and assembly code?
...erence is that managed code “manages” the resources (mostly the memory allocation) for you by employing garbage collection and by keeping references to objects opaque. Unmanaged code is the kind of code that requires you to manually allocate and de-allocate memory, sometimes causing memory leaks...
Why do most C developers use define instead of const? [duplicate]
...til runtime and can only be used for automatic variables (i.e. can only be allocated on the stack).
– Bart van Ingen Schenau
Oct 27 '10 at 12:44
4
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Constant Amortized Time
... takes constant time (that is, O(1)). But each time the array is full, you allocate twice as much space, copy your data into the new region, and free the old space. Assuming allocates and frees run in constant time, this enlargement process takes O(n) time where n is the current size of the array.
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Difference between “on-heap” and “off-heap”
...y point to). This is important because a direct ByteBuffer (the ByteBuffer.allocateDirect kind, not the MMap kind) will be collected by the GC and when it gets collected it's Deallocater will get triggered, effectively collecting the unmanaged memory as well.
– Nitsan Wakart
...
Adding a UILabel to a UIToolbar
...
Have a look into this
[[UIBarButtonItem alloc] initWithCustomView:yourCustomView];
Essentially every item must be a "button" but they can be instantiated with any view you require. Here is some example code. Note, since other buttons are typically on the toolbar,...
What C++ Smart Pointer Implementations are available?
...t calls delete upon destruction making them unacceptable for holding array allocated objects (new[]). It takes ownership of the pointer so two auto pointers shouldn't contain the same object. Assignment will transfer ownership and reset the rvalue auto pointer to a null pointer. Which leads to perha...
Should arrays be used in C++?
...to use traditional C arrays in C++, or should they be avoided, just like malloc ?
11 Answers
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In C#, why is String a reference type that behaves like a value type?
...e (in all implementations of the CLR as of yet) stored on the stack. Stack allocating strings would break all sorts of things: the stack is only 1MB for 32-bit and 4MB for 64-bit, you'd have to box each string, incurring a copy penalty, you couldn't intern strings, and memory usage would balloon, et...
Best way to remove from NSMutableArray while iterating?
.... That may be true (although what about the memory and processing cost of allocating a new array, and discarding the old one?) but even if it's faster it may not be as big a deal as it would be for a naive implementation, because NSArrays do not behave like "normal" arrays. They talk the talk but ...