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Does ARC support dispatch queues?
...
The short answer: YES, ARC retains and releases dispatch queues.
And now for the long answer…
If your deployment target is lower than iOS 6.0 or Mac OS X 10.8
You need to use dispatch_retain and dispatch_release on your queue. ARC does not manage ...
Programmatically get height of navigation bar
...ure out if MoreViewController is showing? (If so, what do you want to do?) and if not, could you clarify what exactly you mean?
– Sum
Sep 5 '11 at 22:32
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How can I set the aspect ratio in matplotlib?
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Third times the charm. My guess is that this is a bug and Zhenya's answer suggests it's fixed in the latest version. I have version 0.99.1.1 and I've created the following solution:
import matplotlib.pyplot as plt
import numpy as np
def forceAspect(ax,aspect=1):
im = ax.g...
Difference in System. exit(0) , System.exit(-1), System.exit(1 ) in Java
...er programming languages where it's useful to know if something went wrong and what went wrong.
Exit code is
0 when execution went fine;
1, -1, whatever != 0 when some error occurred, you can use different values for different kind of errors.
If I'm correct exit codes used to be just positive n...
Cell spacing in UICollectionView
...in case anyone still needs correct answer here what you need:
Override standard flow layout.
Add implementation like that:
- (NSArray *) layoutAttributesForElementsInRect:(CGRect)rect {
NSArray *answer = [super layoutAttributesForElementsInRect:rect];
for(int i = 1; i < [answer count]...
Disable activity slide-in animation when launching new activity?
... another activity, via a button click. By default, on newer OS versions of android, the OS will animate the new activity sliding in from right to left.
...
Swift equivalent for MIN and MAX macros
In C / Objective-C it is possible to find the minimum and maximum value between two numbers using MIN and MAX macros. Swift doesn't support macros and it seems that there are no equivalents in the language / base library. Should one go with a custom solution, maybe based on generics like this one ?...
Regular expression for letters, numbers and - _
...iteral .
References
regular-expressions.info/Anchors, Character Classes and Repetition
In PHP
Here's a snippet to show how you can use this pattern:
<?php
$arr = array(
'screen123.css',
'screen-new-file.css',
'screen_new.js',
'screen new file.css'
);
foreach ($arr as $s) {
if...
Difference between '..' (double-dot) and '…' (triple-dot) in range generation?
I've just started learning Ruby and Ruby on Rails and came across validation code that uses ranges:
5 Answers
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Checking to see if one array's elements are in another array in PHP
... why in PHP docs about this function they say "Returns FALSE if var exists and has a non-empty, non-zero value. Otherwise returns TRUE. The following things are considered to be empty: array() (an empty array)"? Source: php.net/manual/en/function.empty.php
– Pere
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