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Looking to understand the iOS UIViewController lifecycle
...the screen.
ViewDidAppear - Called after the view appears - great place to start an animations or the loading of external data from an API.
ViewWillDisappear/DidDisappear - Same idea as ViewWillAppear/ViewDidAppear.
ViewDidUnload/ViewDidDispose - In Objective-C, this is where you do your clean-up an...
How to check whether a file is empty or not?
...en at this point.. now what?
... my_file.seek(0) #ensure you're at the start of the file..
... first_char = my_file.read(1) #get the first character
... if not first_char:
... print "file is empty" #first character is the empty string..
... else:
... my_file.seek(0) #...
What are Runtime.getRuntime().totalMemory() and freeMemory()?
...mory(). The answer is that the JVM allocates memory lazily. Lets say you start your Java process as such:
java -Xms64m -Xmx1024m Foo
Your process starts with 64mb of memory, and if and when it needs more (up to 1024m), it will allocate memory. totalMemory() corresponds to the amount of memory ...
Opening port 80 EC2 Amazon web services [closed]
... Also, check your firewall (as nsof stated). RHEL has iptables started by default. Windows has windows FW. Turn them off and see if that was the problem. If it was, then edit the firewall to allow 80/443 and restart
– Andrew Backer
Feb 28 '14 at ...
Multiprocessing vs Threading Python [duplicate]
...nthreads]
for thread_class, work_size in input_params:
start_time = time.time()
threads = []
for i in range(nthreads):
thread = thread_class(work_size)
threads.append(thread)
thread.start()
for i,...
'printf' vs. 'cout' in C++
...<ctime>
class TimedSection {
char const *d_name;
timespec d_start;
public:
TimedSection(char const *name) :
d_name(name)
{
clock_gettime(CLOCK_REALTIME, &d_start);
}
~TimedSection() {
timespec end;
...
Is Tomcat running?
...a pid file may not exist, it depends on the environment and how tomcat was started. See this answer to create a pid file on startup.
– Alberto de Paola
Sep 25 '16 at 1:59
...
What is “lifting” in Haskell?
...e have liftFoo3, liftFoo4 and so on. However this is often not necessary.
Start with the observation
liftFoo1 :: (a -> b) -> Foo a -> Foo b
But that is exactly the same as fmap. So rather than liftFoo1 you would write
instance Functor Foo where
fmap f foo = ...
If you really want ...
Android studio logcat nothing to show
...
Restarting logcat helps me always.
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Convert integer into its character equivalent, where 0 => a, 1 => b, etc
...pqrstuvwxyz
^ ^
n n+10
By offsetting by 10 the characters start at a instead of 0.
Not entirely sure about how fast running the two different examples client-side would compare though.
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