如何在同一个类的方法中使用一个类的对象？

Question

My problem is the following :

I have 2 classes : MainActivity and Compartment .

MainActivity creates an array myComp[][] of Compartment . Compartment has a static variable called PpN2 , and a public method that calculates PpN2 .

This method has to calculate myComp[x][y] . PpN2 which is a function of myComp[x-1][y].PpN2 .

Question : how can I access myComp[x-1][y].PpN2 in the method that calculates myComp[x][y].PpN2 ?

Answer 1

If it is static variable, you can access using reference (or) using class name.

Example:

Compartment.PpN2

Remember because of static variable, myComp[x][y] (or)myComp[x-1][y] references updates same variable.

Answer 2

It sounds like you need PpN2 to be an instance variable instead of static, and have MainActivity pass myComp[x-1][y] into myComp[x][y].calcPpN2() or whatever the calc method is called.

Alternatively, you could have Compartment hold a reference to the previous one that the PpN2 calc depends on, and pass it in during construction.

The reason that PpN2 should probably be static is that, being static, its value is shared by all instances of type Compartment . As an instance variable, each individual Compartment object will have its own PpN2 value.