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How do I hide a menu item in the actionbar?
I have an action bar with a menuitem. How can I hide/show that menu item?
24 Answers
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Why is $$ returning the same id as the parent process?
I have problem with Bash, and I don't know why.
Under shell, I enter:
6 Answers
6
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What is the difference between an interface and abstract class?
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Interfaces
An interface is a contract: The person writing the interface says, "hey, I accept things looking that way", and the person using the interface says "OK, the class I write looks that way".
An interface is an empty shell. There are only the signatures of the methods,...
MySQL vs MongoDB 1000 reads
I have been very excited about MongoDb and have been testing it lately. I had a table called posts in MySQL with about 20 million records indexed only on a field called 'id'.
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Lock, mutex, semaphore… what's the difference?
...nly one thread to enter the part that's locked and the lock is not shared with any other processes.
A mutex is the same as a lock but it can be system wide (shared by multiple processes).
A semaphore does the same as a mutex but allows x number of threads to enter, this can be used for example to ...
What does it mean for a data structure to be “intrusive”?
...ive used to describe data structures like lists and stacks, but what does it mean?
2 Answers
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Build Eclipse Java Project from Command Line
...urce\MyProject\workspace" -application org.eclipse.jdt.apt.core.aptBuild
It uses the jdt apt plugin to build your workspace automatically. This is also known as a 'Headless Build'. Damn hard to figure out. If you're not using a win32 exe, you can try this:
java -cp startup.jar -noSplash -data "...
Why isn't ProjectName-Prefix.pch created automatically in Xcode 6?
...efix header. Put your imports into the files that need them. Put your definitions into their own files. Put your macros...nowhere. Stop writing macros unless there is no other way (such as when you need __FILE__). If you do need macros, put them in a header and include it.
The prefix header was nec...
Python: try statement in a single line
...no way to compress a try/except block onto a single line in Python.
Also, it is a bad thing not to know whether a variable exists in Python, like you would in some other dynamic languages. The safer way (and the prevailing style) is to set all variables to something. If they might not get set, set ...
How to allow to accept only image files?
...ed, so you should always validate the uploaded file on the server also.
It should work in IE 10+, Chrome, Firefox, Safari 6+, Opera 15+, but support is very sketchy on mobiles (as of 2015) and by some reports this may actually prevent some mobile browsers from uploading anything at all, so be sur...