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Creating a UICollectionView programmatically
...wDataSource,UICollectionViewDelegateFlowLayout>
{
UICollectionView *_collectionView;
}
Implementation File:--
- (void)viewDidLoad
{
[super viewDidLoad];
self.view = [[UIView alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
UICollectionViewFlowLayout *layout=[[UICollect...
Performance of Arrays vs. Lists
...
Very easy to measure...
In a small number of tight-loop processing code where I know the length is fixed I use arrays for that extra tiny bit of micro-optimisation; arrays can be marginally faster if you use the indexer / for form - but IIRC believe it dep...
How to concatenate strings in django templates?
...
I was totally confused by this answer as it uses the include tag instead of the extend tag, but apparently it just works. Though I would recommend Ahsan's own answer as it also workes and is (in my opinion) semantically more correct a...
Event handling for iOS - how hitTest:withEvent: and pointInside:withEvent: are related?
...lementation of hitTest:withEvent: in UIResponder does the following:
It calls pointInside:withEvent: of self
If the return is NO, hitTest:withEvent: returns nil. the end of the story.
If the return is YES, it sends hitTest:withEvent: messages to its subviews.
it starts from the top-level subview, ...
How do you test functions and closures for equality?
...s Lattner wrote on the developer forums:
This is a feature we intentionally do not want to support. There are
a variety of things that will cause pointer equality of functions (in
the swift type system sense, which includes several kinds of closures)
to fail or change depending on optimiz...
How do I select the parent form based on which submit button is clicked?
...l in one form, and I'd like to validate/etc all the forms with only one JS script.
5 Answers
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“No such file or directory” error when executing a binary
I was installing a binary Linux application on Ubuntu 9.10 x86_64. The app shipped with an old version of gzip (1.2.4), that was compiled for a much older kernel:
...
How do I animate constraint changes?
...
Two important notes:
You need to call layoutIfNeeded within the animation block. Apple actually recommends you call it once before the animation block to ensure that all pending layout operations have been completed
You need to call it specifically on the ...
get list from pandas dataframe column
...rame columns are Pandas Series when you pull them out, which you can then call x.tolist() on to turn them into a Python list. Alternatively you cast it with list(x).
import pandas as pd
data_dict = {'one': pd.Series([1, 2, 3], index=['a', 'b', 'c']),
'two': pd.Series([1, 2, 3, 4], inde...
“Variable” variables in Javascript?
...usly consider that). It is possible to access some global variables dynamically via window, but that doesn't work for variables local to a function. Global variables that do not become a property of window are variables defined with let and const, and classes.
There is almost always a better soluti...