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Android: upgrading DB version and adding new table
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1. About onCreate() and onUpgrade()
onCreate(..) is called whenever the app is freshly installed. onUpgrade is called whenever the app is upgraded and launched and the database version is not the same.
2. Incrementing the db version
You ne...
How to automatically add user account AND password with a Bash script?
I need to have the ability to create user accounts on my Linux (Fedora 10) and automatically assign a password via a bash script(or otherwise, if need be).
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What is “thread local storage” in Python, and why do I need it?
...on-local variables (because each function call gets its own set of locals, and threads are always separate function calls.) And even then, only the variables themselves (the names that refer to objects) are local to the function; objects themselves are always global, and anything can refer to them.
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Why does Chrome incorrectly determine page is in a different language and offer to translate?
...we navigate to this particular page, Chrome tells us the page is in Danish and offers to translate. The page is in English, just like every other page in our app. This particular page is an internal testing page that has a few dozen form fields with English labels. I have no idea why Chrome think...
How to check iOS version?
...lable(iOS 9, *) {}
In Objective-C, you need to check the system version and perform a comparison.
[[NSProcessInfo processInfo] operatingSystemVersion] in iOS 8 and above.
As of Xcode 9:
if (@available(iOS 9, *)) {}
The full answer …
In Objective-C, and Swift in rare cases, it's better to...
CSS3 Transparency + Gradient
RGBA is extremely fun, and so is -webkit-gradient , -moz-gradient , and uh... progid:DXImageTransform.Microsoft.gradient ... yeah. :)
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How to convert a String to its equivalent LINQ Expression Tree?
...o you mean by "writing a parser (using Expression under the hood)" Parsing and then generating an expression tree, or does System.Linq.Expressions have some parsing mechanism?
– AK_
Jul 1 '13 at 14:51
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Is there a reason that Swift array assignment is inconsistent (neither a reference nor a deep copy)?
I'm reading the documentation and I am constantly shaking my head at some of the design decisions of the language. But the thing that really got me puzzled is how arrays are handled.
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Better explanation of when to use Imports/Depends
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"Imports" is safer than "Depends" (and also makes a package using it a 'better citizen' with respect to other packages that do use "Depends").
A "Depends" directive attempts to ensure that a function from another package is available by attaching the other pa...
nginx missing sites-available directory
I installed Nginx on Centos 6 and I am trying to set up virtual hosts. The problem I am having is that I can't seem to find the /etc/nginx/sites-available directory.
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