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What is “android:allowBackup”?
... 21) , they have a new lint warning that tells me the next thing on the manifest file (in the application tag):
4 Answers
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Understanding offsetWidth, clientWidth, scrollWidth and -Height, respectively
...raw boxes, determining all the dimensions using JS is not straight-forward if you only have the CSS.
That's why each element has six DOM properties for your convenience: offsetWidth, offsetHeight, clientWidth, clientHeight, scrollWidth and scrollHeight. These are read-only attributes representing t...
What is the use of a private static variable in Java?
If a variable is declared as public static varName; , then I can access it from anywhere as ClassName.varName . I am also aware that static members are shared by all instances of a class and are not reallocated in each instance.
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Delete duplicate records in SQL Server?
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If you don't have a primary key, you can use ORDER BY (SELECT NULL) stackoverflow.com/a/4812038
– Arithmomaniac
Jul 1 '16 at 16:57
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GCD to perform task in main thread
...on the main thread, which happens when the corresponding run loop is run.
If you already are on the main thread, the behaviour is the same: the block is scheduled, and executed when the run loop of the main thread is run.
s...
Calling a function every 60 seconds
Using setTimeout() it is possible to launch a function at a specified time:
13 Answers
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How to drop columns using Rails migration
...:table_name, :column_name, :type, :options within the change method, since if you specify the type reverting the migration is possible. From the documentation: The typeand options parameters will be ignored if present. It can be helpful to provide these in a migration's change method so it can be re...
How can I calculate an md5 checksum of a directory?
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Note that the same checksum will be generated if a file gets renamed. So this doesn't truly fit a "checksum which will uniquely identify the directory as a whole" if you consider file layout part of the signature.
– Valentin Milea
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How to generate a random alpha-numeric string?
...ric string. In my situation it would be used as a unique session/key identifier that would "likely" be unique over 500K+ generation (my needs don't really require anything much more sophisticated).
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What is the difference between Θ(n) and O(n)?
...g because nobody knows how to type this symbol, or does it mean something different?
9 Answers
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