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How can I maintain fragment state when added to the back stack?

... back stack. However, when I return to FragmentA (by pressing back), a totally new FragmentA is created and the state it was in is lost. I get the feeling I'm after the same thing as this question, but I've included a complete code sample to help root out the issue: ...
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What are the applications of binary trees?

...ningless - they are not a data structure, but a family of data structures, all with different performance characteristics. While it is true that unbalanced binary trees perform much worse than self-balancing binary trees for searching, there are many binary trees (such as binary tries) for which "b...
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__proto__ VS. prototype in JavaScript

...x = x; this.y = y; } var myPoint = new Point(); // the following are all true myPoint.__proto__ == Point.prototype myPoint.__proto__.__proto__ == Object.prototype myPoint instanceof Point; myPoint instanceof Object; Here Point is a constructor function, it builds an object (data structure) p...
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Set Django IntegerField by choices=… name

... Really like the Encapsulation section on the blog. – Nathan Keller Mar 3 '13 at 21:57 ...
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Check if OneToOneField is None in Django

... Thank you for this solution. Unfortunately, this doesn't work all the time. In case you want to work with select_related() now or in the future -- or maybe even to be sure you also handle other sorts of magic which may happen elsewhere -- you have to extend the test as follows: if hasat...
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Correct use of Multimapping in Dapper

...ID, CustomerName. This makes the spliton: parameter not so useful, especially when you're not sure what order the columns are returned in. Of course you could manually specify columns...but it's 2017 and we just rarely do that anymore for basic object gets. What we do, and it's worked great fo...
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Creating the Singleton design pattern in PHP5

... /** * Singleton class * */ final class UserFactory { /** * Call this method to get singleton * * @return UserFactory */ public static function Instance() { static $inst = null; if ($inst === null) { $inst = new UserFactory(); ...
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Static files in Flask - robot.txt, sitemap.xml (mod_wsgi)

... achieved.) it's not clean to add static files into the app root folder finally, the proposed solution looks much cleaner than the adding middleware approach: share | improve this answer |...
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How do I log a Python error with debug information?

...g.exception("message") Output: ERROR:root:message Traceback (most recent call last): File "<stdin>", line 2, in <module> ZeroDivisionError: integer division or modulo by zero @Paulo Cheque notes, "be aware that in Python 3 you must call the logging.exception method just inside the ex...
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Select count(*) from multiple tables

How can I select count(*) from two different tables (call them tab1 and tab2 ) having as result: 18 Answers ...