delegation

What is a C++ delegate?

由 巧了我就是萌 提交于 2019-11-26 12:35:37
What is the general idea of a delegate in C++? What are they, how are they used and what are they used for? I'd like to first learn about them in a 'black box' way, but a bit of information on the guts of these things would be great too. This is not C++ at its purest or cleanest, but I notice that the codebase where I work has them in abundance. I'm hoping to understand them enough, so I can just use them and not have to delve into the horrible nested template awfulness. These two The Code Project articles explain what I mean but not particularly succinctly: Member Function Pointers and the

What is meant by .delegate=self?

由 十年热恋 提交于 2019-11-26 07:57:30
问题 Could anyone explain the meaning of someViewController.delegate = self and self.delegate ? Where do they help us? 回答1: Delegates send messages to you. For example: if you use the accelerometer delegate, you will get messages about the accelerometer. If you use that new neutrino-detection delegate, you will get messages about any neutrinos detected in the area. If you use PopUps, PopUps send you messages. And the way that is done, is with the PopUp's delegate. There are many, many examples. So

Why aren't superclass __init__ methods automatically invoked?

由 感情迁移 提交于 2019-11-26 04:59:07
问题 Why did the Python designers decide that subclasses\' __init__() methods don\'t automatically call the __init__() methods of their superclasses, as in some other languages? Is the Pythonic and recommended idiom really like the following? class Superclass(object): def __init__(self): print \'Do something\' class Subclass(Superclass): def __init__(self): super(Subclass, self).__init__() print \'Do something else\' 回答1: The crucial distinction between Python's __init__ and those other languages

What is a C++ delegate?

由 妖精的绣舞 提交于 2019-11-26 03:46:32
问题 What is the general idea of a delegate in C++? What are they, how are they used and what are they used for? I\'d like to first learn about them in a \'black box\' way, but a bit of information on the guts of these things would be great too. This is not C++ at its purest or cleanest, but I notice that the codebase where I work has them in abundance. I\'m hoping to understand them enough, so I can just use them and not have to delve into the horrible nested template awfulness. These two The

Examples of Delegates in Swift [closed]

由 情到浓时终转凉″ 提交于 2019-11-26 00:48:17
问题 Closed . This question needs to be more focused. It is not currently accepting answers. Want to improve this question? Update the question so it focuses on one problem only by editing this post. Closed 12 months ago . I have been trying to learn how delegation with protocols work. I understood everything, but I can\'t think of when to use delegation other than when using table views and possibly scroll views. In general, when is delegation used? 回答1: What is Delegation? First of all, you

Delegates in swift?

由 不打扰是莪最后的温柔 提交于 2019-11-25 22:37:21
问题 How does one go about making a delegate, i.e. NSUserNotificationCenterDelegate in swift? 回答1: It is not that different from obj-c. First, you have to specify the protocol in your class declaration, like following: class MyClass: NSUserNotificationCenterDelegate The implementation will look like following: // NSUserNotificationCenterDelegate implementation func userNotificationCenter(center: NSUserNotificationCenter, didDeliverNotification notification: NSUserNotification) { //implementation }
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