Why does Android automatically invoke the Onscroll method when it does not scroll when the ListView is first displayed, from the source code analysis

When we do a ListView batch load, we need to call Setonscrolllistener for the ListView (Specific code visible in my previous blog)

However, we will find that the ListView does not scroll when running the program, so why does the system call the Onscroll method? (Supplemental: onscrollstatechanged is not called at this time)

Let's look at Setonscrolllistener source code first:

public void Setonscrolllistener (Onscrolllistener l) {        monscrolllistener = l;        Invokeonitemscrolllistener ();    }

Setonscrolllistener inside called the Invokeonitemscrolllistener () method, and then see the method source code:

void  Invokeonitemscrolllistener () {        if (mfastscroller! = null) {             Mfastscroller.onscroll (mfirstposition, Getchildcount (), mitemcount);         }         if (Monscrolllistener! = null) {            Monscrolllistener.onscroll (this, mfirstposition, Getchildcount (), mitemcount);// Call onscroll here, everything is out of the truth.         }         Onscrollchanged (0, 0, 0, 0); Dummy values, View ' s implementation does not use these.       }