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How to check visibility of software keyboard in Android?
I need to do a very simple thing - find out if the software keyboard is shown. Is this possible in Android?
42 Answers
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Regular expression that matches valid IPv6 addresses
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IPv4 segments should not include leading zeros. If a leading zero is present, the IPv4 segment should be interpreted in octal. So the IPV4SEG above is correct in not allowing '000'. It does however permit '00' which it should not.
– par
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How to “test” NoneType in python?
...value. So how can I question a variable that is a NoneType? I need to use if method, for example
7 Answers
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Regex lookahead for 'not followed by' in grep
...more powerful tool than the standard grep. You need a PCRE-enabled grep.
If you have GNU grep, the current version supports options -P or --perl-regexp and you can then use the regex you wanted.
If you don't have (a sufficiently recent version of) GNU grep, then consider getting ack.
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Doing something before program exit
...e atexit module:
http://docs.python.org/library/atexit.html
For example, if I wanted to print a message when my application was terminating:
import atexit
def exit_handler():
print 'My application is ending!'
atexit.register(exit_handler)
Just be aware that this works great for normal ter...
How to escape double quotes in JSON
...ation marks except for the characters that must be escaped and then it specifies: \" represents the quotation mark character (U+0022)
– mastazi
Mar 30 '17 at 1:30
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How can I generate a list of files with their absolute path in Linux?
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If you give find an absolute path to start with, it will print absolute paths. For instance, to find all .htaccess files in the current directory:
find "$(pwd)" -name .htaccess
or if your shell expands $PWD to the current ...
In log4j, does checking isDebugEnabled before logging improve performance?
...re up-to-date logging framework where the log statements take a format specification and a list of arguments to be substituted by the logger—but "lazily," only if the logger is enabled. This is the approach taken by slf4j.
See my answer to a related question for more information, and an example o...
String's Maximum length in Java - calling length() method
...n is implemented for Strings), Chapter 10: Arrays of The Java Language Specification, Java SE 7 Edition says the following:
The variables contained in an array
have no names; instead they are
referenced by array access expressions
that use nonnegative integer index
values. These variable...
Finding quaternion representing the rotation from one vector to another
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@sinisterchipmunk Actually, if v1 = v2, crossproduct would be (0,0,0) and w would be positive, which normalizes to identity. According to gamedev.net/topic/… it should work just fine also for v1 = -v2 and in their close vicinity.
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