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UIImagePickerController error: Snapshotting a view that has not been rendered results in an empty sn
...ion code
- (void)showcamera {
imagePicker = [[UIImagePickerController alloc] init];
[imagePicker setDelegate:self];
[imagePicker setSourceType:UIImagePickerControllerSourceTypeCamera];
[imagePicker setAllowsEditing:YES];
[self presentModalViewController:imagePicker animated:YES...
Can you attach a UIGestureRecognizer to multiple views?
...matically UITapGestureRecognizer *tapRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(didPressed:)]; [self.view1 addGestureRecognizer:tapRecognizer]; [self.view2 addGestureRecognizer:tapRecognizer]; Output view1 has no gesture recognizers array ; view2 has got ges...
Fast way to discover the row count of a table in PostgreSQL
...s. You can use a subquery with LIMIT:
SELECT count(*) FROM (SELECT 1 FROM token LIMIT 500000) t;
Postgres actually stops counting beyond the given limit, you get an exact and current count for up to n rows (500000 in the example), and n otherwise. Not nearly as fast as the estimate in pg_class, t...
Programmatically set the initial view controller using Storyboards
...ngWithOptions:(NSDictionary *)launchOptions
{
self.window = [[UIWindow alloc] initWithFrame:UIScreen.mainScreen.bounds];
UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"MainStoryboard" bundle:nil];
UIViewController *viewController = // determine the initial view controlle...
When to use -retainCount?
...meaningless.
If you're trying to track down why an object isn't getting deallocated, use the Leaks tool in Instruments. If you're trying to track down why an object was deallocated too soon, use the Zombies tool in Instruments.
But don't use -retainCount. It's a truly worthless method.
edit
Pl...
Does Parallel.ForEach limit the number of active threads?
...s, based on how many you physically have and how many are already busy. It allocates work for each core and then uses a technique called work stealing to let each thread process its own queue efficiently and only need to do any expensive cross-thread access when it really needs to.
Have a look at t...
How to convert a std::string to const char* or char*?
...t chance that your string implementation will need to do some extra memory allocation and/or data copying in order to prepare the NUL terminated buffer
As a further hint, if a function's parameters require the (const) char* but don't insist on getting x.size(), the function probably needs an ASCII...
How to “return an object” in C++?
...hat, you'd probably want to do the out parameter. It avoids dynamic memory allocation, which is safer and generally faster. It does require you have some way to construct the object prior to calling the function, which doesn't always make sense for all objects.
If you want to use dynamic allocation...
Ruby: How to turn a hash into HTTP parameters?
... a good example:
require 'rack'
Rack::Utils.build_query(
authorization_token: "foo",
access_level: "moderator",
previous: "index"
)
# => "authorization_token=foo&access_level=moderator&previous=index"
It even handles arrays:
Rack::Utils.build_query( {:a => "a", :b => ["c...
POST JSON to API using Rails and HTTParty
...ave an api and instructions as follows. You need to authenticate and get a token and then submit the ticket with the token. From squishlist.
...