C ++ (with reference from the other party) Design Mode

In Java, there is a design pattern called holding the references of the other party.

 

However, in C ++, there are more powerful pointers. So that this design mode is not a design mode.

 

Let's take a look at how to use it.

 

 

First, let's look at a phenomenon.

 

Suppose there are Class A and Class B

 

If a contains a member variable of the B object type

B has a member variable of the type.

 

Then, the constructor B will be called when the object A is instantiated, And the constructor A will be called when the constructor B is called. This is an endless loop.

So what should I do if I really need this design?

 

At this time, the pointer becomes very powerful. (Of course, you can refer to the design mode referenced by the owner of Java)

You only need to have a pointer of the B type in a and a pointer of the type in B.

Of course, after doing so, it doesn't mean that everything is fine.

Constructor A and constructor B cannot call the constructor of the other party at the same time.

 

If neither of them calls the constructor of the other party, this is also possible, as long as there is a set method. So as to achieve the goal.

But the simple method is:

In a, new B. In B's constructor, set the parameter to (*).

A ()

{

New B (this)

}