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What is the purpose of willSet and didSet in Swift?
... for instance to notify other objects that the property just changed. When all you have is get/set, you need another field to hold the value. With willSet and didSet, you can take action when the value is modified without needing another field. For instance, in that example:
class Foo {
var myP...
How to resize superview to fit all subviews with autolayout?
...n a UITableViewCell (to determine row height for example) then you should call it against your cell contentView and grab the height.
Further considerations exist if you have one or more UILabel's in your view that are multiline. For these it is imperitive that the preferredMaxLayoutWidth propert...
Convert decimal to binary in python [duplicate]
...
all numbers are stored in binary. if you want a textual representation of a given number in binary, use bin(i)
>>> bin(10)
'0b1010'
>>> 0b1010
10
...
How does Facebook disable the browser's integrated Developer Tools?
... link; ours is a little more complicated for no good reason.
Chrome wraps all console code in
with ((console && console._commandLineAPI) || {}) {
<code goes here>
}
... so the site redefines console._commandLineAPI to throw:
Object.defineProperty(console, '_commandLineAPI',
{...
Remove secure warnings (_CRT_SECURE_NO_WARNINGS) from projects by default in Visual Studio
Is there a way to set by default for all projects removing the precompiler secure warnings that come up when using functions like scanf(). I found that you can do it by adding a line in the project option or a #define _CRT_SECURE_NO_WARNINGS in the beginning of the code.
...
After Installing Java JDK 7 For Mac OS X - mvn -version still shows java version 1.6.0_31
Oracle released Java JDK 7 on April 26 for Mac OS X. I followed the install instructions and when I do java -version in a terminal window I get:
...
Why dict.get(key) instead of dict[key]?
...
It allows you to provide a default value if the key is missing:
dictionary.get("bogus", default_value)
returns default_value (whatever you choose it to be), whereas
dictionary["bogus"]
would raise a KeyError.
If omitted...
JRE 1.7 - java version - returns: java/lang/NoClassDefFoundError: java/lang/Object
...
This problem stems from an improper Java installation.
Possibility 1
NOTE: This scenario only applies to Java 8 and prior. Beginning with Java 9, the JRE is structured differently. rt.jar and friends no longer exist, and Pack200 is no longer used.
The Java standa...
Undocumented NSURLErrorDomain error codes (-1001, -1003 and -1004) using StoreKit
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All error codes are on "CFNetwork Errors Codes References" on the documentation (link)
A small extraction for CFURL and CFURLConnection Errors:
kCFURLErrorUnknown = -998,
kCFURLErrorCancelled = -999,
kCFURLErrorBadU...
Algorithm to detect corners of paper sheet in photo
...n are awesome, move to them as soon as possible. :D
Instead of removing small objects and or noise, lower the canny restraints, so it accepts more edges, and then find the largest closed contour (in OpenCV use findcontour() with some simple parameters, I think I used CV_RETR_LIST). might still stru...