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Difference between addSubview and insertSubview in UIView class
...array then add in View'slayer
- (void)addSubview:(UIView *)subview
{
[_subviews addObject:subview];
[_layer addSublayer:subview.layer];
}
}
2.While insertSubview add your view as subview then call
[_layer insertSublayer:subview.layer atIndex:index];
- (void)insertSubview:(UIView *)subv...
Is there any overhead to declaring a variable within a loop? (C++)
...
Stack space for local variables is usually allocated in function scope. So no stack pointer adjustment happens inside the loop, just assigning 4 to var. Therefore these two snippets have the same overhead.
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How do I pass the this context to a function?
...
Javascripts .call() and .apply() methods allow you to set the context for a function.
var myfunc = function(){
alert(this.name);
};
var obj_a = {
name: "FOO"
};
var obj_b = {
name: "BAR!!"
};
Now you can call:
myfunc.ca...
Application_Error not firing when customerrors = “On”
...the HandleErrorAttribute tells MVC to look for an Error view and it never calls the Application_Error() method. I couldn't find documentation of this but it is explained in this answer on programmers.stackexchange.com.
To get the ApplicationError() method called for every unhandled exception, simpl...
How to solve the error LNK2019: unresolved external symbol - function?
...l but have not declared that class itself as import/export.
#ifdef MYDLL_EXPORTS
#define DLLEXPORT __declspec(dllexport)
#else
#define DLLEXPORT __declspec(dllimport)
#endif
class DLLEXPORT Book // <--- this class must also be declared as export/import
{
public:
Book();
...
Is std::unique_ptr required to know the full definition of T?
...s. However shared_ptr and unique_ptr are partial exceptions. Some, but not all of their members can be instantiated with incomplete types. The motivation for this is to support idioms such as pimpl using smart pointers, and without risking undefined behavior.
Undefined behavior can occur when you h...
CSS hexadecimal RGBA?
... to #00FF00).
8 digits
The first 6 digits are interpreted identically to the 6-digit notation. The last pair of digits, interpreted as a hexadecimal number, specifies the alpha channel of the color, where 00 represents a fully transparent color and ff represent a fully opaque color.
...
Which @NotNull Java annotation should I use?
... with each others' @NotNull / @NonNull / @Nonnull annotation and listing all of them in my code would be terrible to read. Any suggestions of which one is the 'best'? Here is the list of equivalent annotations I've found:
...
Techniques for Tracing Constraints
... and GHC complains could not deduce x ~ y for some x and y . You can usually throw GHC a bone and simply add the isomorphism to the function constraints, but this is a bad idea for several reasons:
...
Xcode stuck at “Your application is being uploaded”
... just keep your head cool and check this first method:
Check if your firewall protection is off. If not then turn it off. It maybe blocking you to connect your computer with iTunes
Store.
Try a different internet connection. The purpose for trying a different internet connection is that your curre...