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Click Event on UIImageView programmatically in ios

...jective-c UITapGestureRecognizer *singleTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tapDetected)]; singleTap.numberOfTapsRequired = 1; [preArrowImage setUserInteractionEnabled:YES]; [preArrowImage addGestureRecognizer:singleTap]; -(void)tapDetected{ NSLog(@"si...
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What is Haskell used for in the real world? [closed]

...h closures), strong typing (TypeInference), GarbageCollection, storage allocation, whether to use boxed (pointer-to-value) or unboxed (value directly) representation... Safe multithreading! Immutable data structures are not subject to data race conditions, and consequently don't have to be p...
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Real World Use of Zookeeper [closed]

...Found, for example, we use ZooKeeper extensively for discovery, resource allocation, leader election and high priority notifications. In this article, we'll introduce you to this King of Coordination and look closely at how we use ZooKeeper at Found ...
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How do I concatenate two lists in Python?

...ise fashion, which means this is a quadratic operation as memory has to be allocated for each step. DO NOT USE if your lists are large. See chain and chain.from_iterable from the docs. You will need to import itertools first. Concatenation is linear in memory, so this is the best in terms of perfor...
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Null or default comparison of generic argument in C#

...ur example since the program exits straight away. However, every box is an allocation. If you deal with anything non-trivial, avoiding unnecessary allocations is always to be recommended. These allocations are unnecessary. – Marc Gravell♦ Nov 7 '17 at 17:28 ...
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How to check which locks are held on a table

...AS P ON P.hobt_id = TL.resource_associated_entity_id LEFT OUTER JOIN sys.allocation_units AS AU ON AU.allocation_unit_id = TL.resource_associated_entity_id; share | improve this answer ...
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Pull to refresh UITableView without UITableViewController

...able view. Same as in the case of collection view. Just replace table view alloc with collection view. UITableView *tableViewDemo = [[UITableView alloc]init]; tableViewDemo.frame = CGRectMake(0,0,self.view.frame.size.width,self.view.frame.size.height); tableViewDemo.dataSource = self; tableView...
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UIRefreshControl on UICollectionView only works if the collection fills the height of the container

... a UIRefreshControl UIRefreshControl *refreshControl = [[UIRefreshControl alloc] init]; refreshControl.tintColor = [UIColor grayColor]; [refreshControl addTarget:self action:@selector(refershControlAction) forControlEvents:UIControlEventValueChanged]; [self.collectionView addSubview:refreshControl]...
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Weak and strong property setter attributes in Objective-C

...t point to it anymore" - in other words " I'am the owner, you cannot dealloc this before aim fine with that same as retain" - You use strong only if you need to retain the object. - By default all instance variables and local variables are strong pointers. - We generally use strong f...
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Speed up the loop operation in R

...s, then fill them in, rather than expanding them each time. Even with pre-allocation, you could switch to a pass-by-reference approach rather than a pass-by-value approach, but it may not be worth the hassle. Take a look at the R Inferno for more pitfalls to avoid. Try for better vectorization...