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Objective-C: Where to remove observer for NSNotification?
...his is obviously not a satisfying answer.
I'd recommend, that you add a call [notificationCenter removeObserver: self] in method dealloc of those classes, which you intend to use as observers, as it is the last chance to unregister an observer cleanly. This will, however, only protect you against ...
Remote debugging Tomcat with Eclipse
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Actually, yours did fix it. Eclipse doesn't actually say anything when it successfully connects, and reconnecting a second time forces the error. So it was working, but I just didn't notice.
– victor
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When to encode space to plus (+) or %20?
...value is query value with a space, but the folder name in the path is literally foo+bar, not foo bar.
%20 is a valid way to encode a space in either of these contexts. So if you need to URL-encode a string for inclusion in part of a URL, it is always safe to replace spaces with %20 and pluses with ...
How to generate a random int in C?
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Note: Don't use rand() for security. If you need a cryptographically secure number, see this answer instead.
#include <time.h>
#include <stdlib.h>
srand(time(NULL)); // Initialization, should only be called once.
int r = rand(); // Returns a pseudo-random integer bet...
“Insufficient Storage Available” even there is lot of free space in device memory
The total space of my app is 10 MB, and after installation it will take less than 20 MB. In Galaxy Note I , while updating my app, it's saying "Insufficient Storage Available", where there is 214 MB of free space in device memory (internal). It happens even trying to download a new app.
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Rotating and spacing axis labels in ggplot2
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Change the last line to
q + theme(axis.text.x = element_text(angle = 90, vjust = 0.5, hjust=1))
By default, the axes are aligned at the center of the text, even when rotated. When you rotate +/- 90 degrees, you usually want it to be aligned at the edge instead:
The image ab...
How to get Twitter-Bootstrap navigation to show active link?
...g the same code over and over. I would recommend at least using the current_page? method to check the current controller/action, and would also move the code into a helper to avoid the code repetition.
– Dustin Frazier
May 9 '12 at 17:17
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Converting from a string to boolean in Python?
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Use:
bool(distutils.util.strtobool(some_string))
Python 2: http://docs.python.org/2/distutils/apiref.html?highlight=distutils.util#distutils.util.strtobool
Python 3: https://docs.python.org/3/distutils/apiref.html#distutils.util.strtobool
True values are y...
MySQL “WITH” clause
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Update: MySQL 8.0 is finally getting the feature of common table expressions, including recursive CTEs.
Here's a blog announcing it: http://mysqlserverteam.com/mysql-8-0-labs-recursive-common-table-expressions-in-mysql-ctes/
Below is my earlier answ...
grep a file, but show several surrounding lines?
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Ok, but what if want to show all lines of output after the match? grep -A0 and grep -A-1 don't cut it...
– g33kz0r
Jul 22 '11 at 2:18
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