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Android. Fragment getActivity() sometimes returns null

...eFragment() { // Implement the Parent. super(); // Allocate the ActivityBuffer. this.mActivityBuffer = new ActivityBuffer(); } @Override public final void onAttach(final Context pContext) { // Handle as usual. super.onAttach(pContext); ...
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Initializing a struct to 0

...so just declare it myStruct _m; If the data is a local variable or a heap-allocated zone, clear it with memset like: memset(&m, 0, sizeof(myStruct)); Current compilers (e.g. recent versions of gcc) optimize that quite well in practice. This works only if all zero values (include null pointer...
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How do I design a class in Python?

...l methods. Go through the adjectives, looking for potential attributes Allocate methods and attributes to your classes To refine the class, the book also advises we can do the following: Write down (or dream up) a set of use cases—scenarios of how your program may be used. Try to c...
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How to check if running in Cygwin, Mac or Linux?

...LAGS += -DNDEBUG endif ifeq ($(uname_S),GNU/kFreeBSD) CFLAGS += -D_BSD_ALLOC endif ifeq ($(uname_S),UnixWare) CFLAGS += -Wextra endif ... See also this complete answer about uname -s and Makefile. The correspondence table in the bottom of this answer is from Wikipedia article about uname. P...
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C++ STL Vectors: Get iterator from index?

...s of a vector are stored contiguously, meaning that if v is a vector<T, Allocator> where T is some type other than bool, then it obeys the identity &v[n] == &v[0] + n for all 0 <= n < v.size()" – yves Baumes Sep 17 '12 at 21:07 ...
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Summarizing multiple columns with dplyr? [duplicate]

...#> # A tibble: 3 x 6 #> expression min median `itr/sec` mem_alloc `gc/sec` #> <bch:expr> <bch:tm> <bch:tm> <dbl> <bch:byt> <dbl> #> 1 dplyr 2.81ms 2.85ms 328. NA 17.3 #> 2 purrrlyr 7.96ms 8.04ms ...
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What does @synchronized() do as a singleton method in objective C?

...ES NOT do the same as @syncrhonized, it can be a substitute ONLY under the allocation of a singleton. – jugutier Aug 22 '16 at 21:32 add a comment  |  ...
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Why is Linux called a monolithic kernel?

...FS, device drivers, etc) as well as core functionality (scheduling, memory allocation, etc.) are a tight knit group sharing the same space. This directly opposes a microkernel. A microkernel prefers an approach where core functionality is isolated from system services and device drivers (which are ...
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Difference between InvariantCulture and Ordinal string comparison

...ld days before computers had lowercase letters, the uppercase letters were allocated first and thus had lower values than the lowercase letters added later). For example, by Ordinal: "0" < "9" < "A" < "Ab" < "Z" < "a" < "aB" < "ab" < "z" < "Á" < "Áb" < "á" < "...
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How to list active / open connections in Oracle?

... For a more complete answer see: http://dbaforums.org/oracle/index.php?showtopic=16834 select substr(a.spid,1,9) pid, substr(b.sid,1,5) sid, substr(b.serial#,1,5) ser#, substr(b.machine,1,6) box, substr(b.username,1,10) username, -- b.server, ...