design patterns explained simply

show through proxies. For example, a network request comes back, it is better to show it by success, failure code block. Performance, the performance of the block is slightly larger than delegate, because the block will involve the stack area to the heap copy operations, time and space consumption is greater than the agent. Instead, the agent simply defines a list of methods, adds a node to the objc_protocol_list that adheres to the Protocol obje

give a code to implement the Registrar. The benefit of creating a singleton pattern with the registrar mechanism is that it is easy to manage and can control multiple different types of singleton instances at the same time. Summary 1. The singleton model can be easily expanded to produce a specified number of instances. 2. In the design Patterns Java Companion, it has been mentioned that using static cl

How to skillfully use the dark patterns in interactive design, we need more thinking and learning. Do not mind the user scold you rogue, that means you rascal's not clever. Today this good article takes you to see which looks very stupid actually very ingenious interactive design, the case all is from the domestic website/app, very has the reference. Some operat

complex, there are many properties, and these properties are references to other objects, which may include a lot of object references. By encapsulating these complexities, you can use the build mode.Recommended Link: http://www.cnblogs.com/cbf4life/archive/2010/01/14/1647710.html4. Façade modeThis pattern feels like a replica of the service layer. For example DAO we define a lot of persistence methods, we use the service layer to make the DAO atomic method into business logic, and then provide

of design patterns. This article first introduces the use of simple delegates.What is a delegate: a Delegate in C # (Delegate) is similar to a pointer to a function in C or C + +. In the blogger's words, a delegate is a reference type that allows a method name to be passed as a parameter. It defines the type of method, which can be said to be the abstraction of a method, then conversely, the method can be

() { alert (this.name); }}; var person1 = new Person (), var person2 = new Person (); Person1.friends.push ("Van"); alert (person1.friends);//"Shelby,court,van" alert (person2.friends);//"Shelby,court,van" alert (person1.friends=== Person2.friends); TrueHere, the Person.prototype object has a property named friends that contains an array of strings. Then, two instances of person are created. Next, an array of person1.friends references is modified, and a string is added t

In JavaScript, there is no support for abstract classes and interfaces. JavaScript itself is also a weakly typed language. JavaScript does not have the ability or need to do more in terms of encapsulation types. For JavaScript design pattern implementations, the distinction between types is a pale, or a relief. From the point of view of design pattern, encapsulation is reflected in the more important aspec

This book should be the most interesting one I have read so far. It contains many illustrations, humorous words, and often uses anthropomorphic methods, for example, the dialogue between the abstract factory and the factory method mode does not mean that the depth is not enough. On the contrary, he explained the problem very thoroughly. This book is very different from the computer books I have read before. It is also based on Reading Notes or Blackbo

Builder Pattern) Once you hear this name, you may guess one or two points. A builder simply understands that it is something to create. It is just something that the builder model creates, not something that is more complex than a hacker. It is like building a house. You need to build a foundation, build a wall, fill cement, seal the top, and tile the last wall. The builder design mode is a

the book to implement the two patterns is completely different (I think this implementation is somewhat arbitrary). the state mode, in particular, uses a separate implementation hierarchy, but I don't think it's necessary unless you assume that the implementation code is not controlled by you (which is, of course, a possibility, but if the code is controlled by you, It is also more concise and practical with a single base class). In addition, the pro

1.JDBC (Javadatabase Connectivity)JDBC is an API that accesses the database in a uniform manner.It provides platform-independent database access, that is, with the JDBC API, we do not have to access the Oracle database to write a program specifically to access the Sybase database and write a program, and so on, only need to write a program with the JDBC API is enough, It can send SQL calls to the appropriate database. JDBC is a mechanism for the way that Java applications interact with various d

nested views. The object of the Compositeview class behaves like a view class object, and a combined view can be used wherever any view is available, but it contains and manages nested views.Divides some objects into a group and uses that group of objects as an object. This design is described as composite (combined mode), which allows you to create a class hierarchy, where some subclasses define atomic objects (such as Button) and other classes defi

the View object, and controls the response events such as triggering events. The View object is the interface logic that the user feels. Android application design is based on the MVC architecture, although strictly speaking, the activity is not simply the role of controller, and the current design patterns a

implementation for all three of these methods. Therefore, any concrete class that inherits from the abstract class Serviceadapter can choose the method implementation that it needs, regardless of the other unwanted methods. 　　the adapter mode is intended to change the interface of the source so that it is compatible with the target interface. The default adaptation is slightly different , and it is a mediocre implementation provided to facilitate the creation of a non-mediocre adapter class.At

The Observer PatternThe Observer is a design pattern where an object (known as a subject) maintains a list of objects depending on it (observe RS), automatically notifying them of any changes to the state.When a subject needs to notify observers on something interesting happening, it broadcasts a notification to the Observ ERS (which can include specific data related to the topic of the notification).When we do longer wish for a particular observer to

First, this program is marked What is a singleton mode Single-Instance pattern class diagram Singleton Pattern Code Application of single-case model Ps:java design Mode Series course, this is the last section of the class. I believe that we learn all the way down or harvest quite abundant, now think back to the learning of those design

variables, overloaded construction methods, execution of abstract methods)Outside of the programming world, there are many examples of policy patterns. For example:If I need to go to work from home in the morning, I can have a few strategies to consider: I can take the subway, take a bus, walk or other way. Each policy can get the same results, but different resources are used.Abstract class Baseagent {//Abstraction policy classAbstract function Prin

something in M changes, C needs to know about these changes, so how can we let C know about m changes? Notifications (Notification) and KVO are good ways to solve problems. That's how they work, and when something in M changes, they send a notice to C, "Hey, man, watch out, I've changed," or they'll send a pointer to change to C, or something. In short, their mode of work is like this.Here's a summary of what we've learned, cocoa is faithful to MVC, so understanding Cocoa's MVC is our key start

1. Single Case design modeThe so-called single-case design mode is simply said that no matter how the program runs, a single-instance design pattern of the class (Singleton Class) will always have only one instantiation of the object generated. The specific implementation steps are as follows:(1) The construction metho

understand it. It would be better if it could help others ~~~ Php single-column mode What is pattern design? At the beginning, beginners will be caught by the tall name. For laruence with rich programming experience, pattern design is everywhere. Many frameworks are designed based on various patterns. Simply put, the