Android sets ListView to scroll to a certain position

Recently, when doing a project has a function is to click a button when the current page to stay in a fixed position, and the current page only a ListView, if it is scrollview, then believe it will be a lot simpler, direct call Scrollview.scrollto ( X,y) or Scrollview.smoothscrollto (X,y), one of these two methods, and then give the specified Y value OK, but if it is ListView, the principle is the same, there are two ways
SetSelection () and Setselectionfromtop ().

If you want to stay in the current 5th item position, that is, let the fifth item top, then direct listview.setselection (5) is OK, but if I want to stay in a more accurate position then I will call Setselectionfromtop () This method, such as I want to stay in the 4th and fifth item in the middle of the position, then assume the fourth item height is 100px, then direct Listview.setselectionfromtop (5,50) on the OK.

Explain the rationale of the two methods: the Setselectionfromtop () function is to set the ListView selected position and set an offset on the y-axis.

The SetSelection () method, passing in an index integer value, allows the ListView to position to the specified item.

Add a List1 and a Command1 to Form1 and add the following code. Press COMMAND1 button after running to see if it's the effect you want

/** Save the position **/
int currentposition = Listview.getfirstvisibleposition ();

Here u should save the currentposition anywhere

/** Restore the Previus saved position **/
Listview.setselection (savedposition);

Of course, you can also use this method:
Save index and top position
int index = mlist.getfirstvisibleposition ();
View v = mlist.getchildat (0);
int top = (v = = null)? 0:v.gettop ();

// ...

Restore
Mlist.setselectionfromtop (index, top);