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Constructor of an abstract class in C#
Why is it possible to write constructor for an abstract class in C#?
As far as I know we can't instantiate an abstract class.. so what is it for?
You can't instantiate the class, right?
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Fragment in ViewPager using FragmentPagerAdapter is blank the second time it is viewed
I have a fragment interface with tabs along the bottom which open different fragments in the main view.
13 Answers
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How do I use shell variables in an awk script?
...best way, most portable)
Use the -v option: (P.S. use a space after -v or it will be less portable. E.g., awk -v var= not awk -vvar=)
variable="line one\nline two"
awk -v var="$variable" 'BEGIN {print var}'
line one
line two
This should be compatible with most awk, and the variable is available ...
What is the purpose of the “final” keyword in C++11 for functions?
...is the purpose of the final keyword in C++11 for functions? I understand it prevents function overriding by derived classes, but if this is the case, then isn't it enough to declare as non-virtual your final functions? Is there another thing I'm missing here?
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uint8_t vs unsigned char
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It documents your intent - you will be storing small numbers, rather than a character.
Also it looks nicer if you're using other typedefs such as uint16_t or int32_t.
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What are the best practices for SQLite on Android?
...hat would be considered the best practices when executing queries on an SQLite database within an Android app?
10 Answers
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NullPointerException in Java with no StackTrace
...mization. To get the stack traces back, you need to pass the option -XX:-OmitStackTraceInFastThrow to the JVM.
The optimization is that when an exception (typically a NullPointerException) occurs for the first time, the full stack trace is printed and the JVM remembers the stack trace (or maybe jus...
Visual Studio displaying errors even if projects build
I have a problem with Visual Studio on a C# solution. It displays totally random errors, but the projects build. Right now, I have 33 files with errors, and I can see red squiggly lines in all of them.
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How is null + true a string?
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Bizarre as this may seem, it's simply following the rules from the C# language spec.
From section 7.3.4:
An operation of the form x op y, where op is an overloadable binary operator, x is an expression of type X, and y is an expression of type Y,...
Is “double hashing” a password less secure than just hashing it once?
... a password twice before storage any more or less secure than just hashing it once?
16 Answers
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