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Android: how to check if a View inside of ScrollView is visible?
I have a ScrollView which holds a series of Views . I would like to be able to determine if a view is currently visible (if any part of it is currently displayed by the ScrollView ). I would expect the below code to do this, surprisingly it does not:
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Is there a way to avoid null check before the for-each loop iteration starts? [duplicate]
Every time I have to iterate over a collection I end up checking for null, just before the iteration of the for-each loop starts. Like this:
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Why there is no ConcurrentHashSet against ConcurrentHashMap
...map (or map class).
Prior to Java 8, you produce a concurrent hash set backed by a concurrent hash map, by using Collections.newSetFromMap(map)
In Java 8 (pointed out by @Matt), you can get a concurrent hash set view via ConcurrentHashMap.newKeySet(). This is a bit simpler than the old newSetFromM...
Simple regular expression for a decimal with a precision of 2
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Valid regex tokens vary by implementation. A generic form is:
[0-9]+(\.[0-9][0-9]?)?
More compact:
\d+(\.\d{1,2})?
Both assume that both have at least one digit before and one after the decimal place.
To require that the whole strin...
How to add a right button to a UINavigationController?
...d it still might be quite a while before it displays, no point in doing work early and tying up memory.
- (void)viewDidLoad {
[super viewDidLoad];
UIBarButtonItem *anotherButton = [[UIBarButtonItem alloc] initWithTitle:@"Show" style:UIBarButtonItemStylePlain target:self action:@selector(refres...
Is there a better way to iterate over two lists, getting one element from each list for each iterati
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Roberto BonvalletRoberto Bonvallet
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How do I remove  from the beginning of a file?
I have a CSS file that looks fine when I open it using gedit , but when it's read by PHP (to merge all the CSS files into one), this CSS has the following characters prepended to it: 
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How does Facebook Sharer select Images and other metadata when sharing my URL?
When using Facebook Sharer, Facebook will offer the user the option of using 1 of a few images pulled from the source as a preview for their link. How are these images selected, and how can I ensure that any particular image on my page is always included in this list?
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Is using Random and OrderBy a good shuffle algorithm?
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It's not a way of shuffling that I like, mostly on the grounds that it's O(n log n) for no good reason when it's easy to implement an O(n) shuffle. The code in the question "works" by basically giving a random (hopefully unique!) number to each element, then ord...
Saving image from PHP URL
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Andrew
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answered Apr 7 '09 at 7:15
vartecvartec
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