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Sending a message to nil in Objective-C
...x:i]; This will also return 0, but since objectAtIndex: returns a pointer, and a pointer to 0 is nil/NULL, NSLog will be passed nil each time through the loop. (Although NSLog is a function and not a method, it prints out (null) if passed a nil NSString.
In some cases it's nicer to have a NullPoint...
How do I make calls to a REST api using C#?
... post an updated answer since most of these responses are from early 2012, and this thread is one of the top results when doing a Google search for "call restful service c#".
Current guidance from Microsoft is to use the Microsoft ASP.NET Web API Client Libraries to consume a RESTful service. This ...
Thread-safe List property
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Like List<T> and unlike Dictionary, ConcurrentBag accepts duplicates.
– The Light
May 24 '12 at 9:17
122
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Input from the keyboard in command line application
I am attempting to get the keyboard input for a command line app for the new Apple programming language Swift.
19 Answers
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If using maven, usually you put log4j.properties under java or resources?
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src/main/resources is the "standard placement" for this.
Update: The above answers the question, but its not the best solution. Check out the other answers and the comments on this ... you would probably not shipping your own logging properties with the...
Error Code: 2013. Lost connection to MySQL server during query
...onds? The DBMS connection read time out field only accept up to 5 figures, and setting the field to 0 is equivalent to the default parameter (600 seconds). (Windows 7 64-bit Ultimate, MySQL Workbench 5.2.47 CE)
– Franck Dernoncourt
Jun 1 '13 at 21:30
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in iPhone App How to detect the screen resolution of the device
...ays this will return a 1.0f, while Retina Display devices will give a 2.0f and the iPhone 6 Plus (Retina HD) will give a 3.0f.
Now if you want to get the pixel width & height of the iOS device screen you just need to do one simple thing.
CGSize screenSize = CGSizeMake(screenBounds.size.width *...
How to perform Unwind segue programmatically?
...oryboardSegue argument; the WWDC 2012 session 407 talk didn't mention that and didn't paste that code in. Without it, my Exit icon wouldn't go active when control-dragging to it. 3) It's pretty cool that at the end of your big red arrow, in the Action field, you can hit the "go there" arrow!
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Coarse-grained vs fine-grained
What is the difference between coarse-grained and fine-grained?
11 Answers
11
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Can an abstract class have a constructor?
... what) {
super(what);
}
}
The superclass Product is abstract and has a constructor. The concrete class TimesTwo has a constructor that just hardcodes the value 2. The concrete class TimesWhat has a constructor that allows the caller to specify the value.
Abstract constructors will fre...