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UIImagePickerController error: Snapshotting a view that has not been rendered results in an empty sn
...Camera in your UIViewController, only after the view has Loaded and with a timeout:
- (void)viewDidAppear:(BOOL)animated
{
[super viewDidAppear:animated];
//show camera...
if (!hasLoadedCamera)
[self performSelector:@selector(showcamera) withObject:nil afterDelay:0.3];
}
and ...
Binary Data in JSON String. Something better than Base64
.... A simple encode+decode timing measurement shows that b85 is more than 13 times slower than b64. So we have a 7% size win, but 1300% performance loss.
– Pieter Ennes
Sep 11 '14 at 12:03
...
The Definitive C++ Book Guide and List
...purely as a reference for experienced users willing to devote considerable time and effort to its understanding. The C++17 standard is released in electronic form for 198 Swiss Francs.
The C++17 standard is available, but seemingly not in an economical form – directly from the ISO it costs 198 Sw...
How can you automatically remove trailing whitespace in vim
I am getting 'trailing whitespace' errors trying to commit some files in git.
13 Answers
...
DESTDIR and PREFIX of make
...Sepcify a different --prefix location/option for each build - at configure time. For eg:
untar petsc tar ball
./configure --prefix=/opt/petsc/petsc-3.9.0-mpich --with-mpi-dir=/opt/mpich
make
make install DESTDIR=/tmp/petsc-pkg
untar petsc tar ball
./configure --prefix=/opt/petsc/petsc-3.9.0-openmpi...
How to forward declare a C++ template class?
...e a templated class whose definition states the default arguments, but any time you reference the class you must include all of its arguments until the definition is introduced.
eg. Let's use std::vector without including it (the second argument of std::vector is defined with a default):
namespace s...
Do htmlspecialchars and mysql_real_escape_string keep my PHP code safe from injection?
...a wrapper like PEAR DB
Make sure that magic_quotes_gpc and magic_quotes_runtime are off at all times, and never get accidentally turned on, not even briefly. These are an early and deeply misguided attempt by PHP's developers to prevent security problems (which destroys data)
There isn't really a ...
How can I search Git branches for a file or directory?
...cript to use it, I found it a little restricted to use that approach.
Sometimes you need to search for something that can appear/disappear over time, so why not search against all commits? Besides that, sometimes you need a verbose response, and other times only commit matches. Here are two version...
Why does InetAddress.isReachable return false, when I can ping the IP address?
...
// in case of Linux change the 'n' to 'c'
Process p1 = java.lang.Runtime.getRuntime().exec("ping -n 1 www.google.com");
int returnVal = p1.waitFor();
boolean reachable = (returnVal==0);
The -c option of ping will allow ping to simply try to reach the server once(as opposed to the in...
Why does i = i + i give me 0?
...
This is my favorite answer on this site ever of all times.
– Lee White
Jun 12 '14 at 14:24
2
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