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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:
...
UICollectionView Set number of columns
...[self.myCollectionView.collectionViewLayout invalidateLayout];
}
Additionally, here are 2 really good tutorials on UICollectionViews:
http://www.raywenderlich.com/22324/beginning-uicollectionview-in-ios-6-part-12
http://skeuo.com/uicollectionview-custom-layout-tutorial
...
How to shuffle a std::vector?
...n Coliru
Make sure to reuse the same instance of rng throughout multiple calls to std::shuffle if you intend to generate different permutations every time!
Moreover, if you want your program to create different sequences of shuffles each time it is run, you can seed the constructor of the random e...
URL rewriting with PHP
...
You can essentially do this 2 ways:
The .htaccess route with mod_rewrite
Add a file called .htaccess in your root folder, and add something like this:
RewriteEngine on
RewriteRule ^/?Some-text-goes-here/([0-9]+)$ /picture.php?id=$1
Thi...
How do you calculate the average of a set of circular data? [closed]
... sum_i_from_1_to_N cos(a[i])
The method given by starblue is computationally equivalent, but his reasons are clearer and probably programmatically more efficient, and also work well in the zero case, so kudos to him.
The subject is now explored in more detail on Wikipedia, and with other uses, l...
How to set the prototype of a JavaScript object that has already been instantiated?
...n set of rules. This is currently unresolved but at least it will be officially part of JavaScript's specification.
This question is a lot more complicated than it seems on the surface, and beyond most peoples' pay grade in regards to knowledge of Javascript internals.
The prototype property of an...
Stop pip from failing on single package when installing with requirements.txt
I am installing packages from requirements.txt
6 Answers
6
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Why is Python running my module when I import it, and how do I stop it?
...program I'm building that can be run in either of 2 ways: the first is to call "python main.py" which prompts the user for input in a friendly manner and then runs the user input through the program. The other way is to call "python batch.py -file- " which will pass over all the friendly input gat...
What is your favorite C programming trick? [closed]
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C99 offers some really cool stuff using anonymous arrays:
Removing pointless variables
{
int yes=1;
setsockopt(yourSocket, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(int));
}
becomes
setsockopt(yourSocket, SOL_SOCKET, SO_REUSEADDR...
How does deriving work in Haskell?
Algebraic Data Types (ADTs) in Haskell can automatically become instances of some typeclasse s (like Show , Eq ) by deriving from them.
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