android--to determine how the ListView slides up and down

1Elv_music_res_fragment.setonscrolllistener (NewAbslistview.onscrolllistener () {2             Private intmlastfirstpostion = 0;3             Private intMlastfirsttop = 0;4             Private intTouchslop =Viewconfiguration.get (Getactivity ()). Getscaledtouchslop ();5 6 @Override7              Public voidOnscrollstatechanged (Abslistview view,intscrollstate) {8 9             }Ten  One @Override A              Public voidOnscroll (Abslistview Abslistview,intFirstvisibleitem,intVisibleItemCount,intTotalitemcount) { -                 intCurrenttop; -  theView Firstchildview = Abslistview.getchildat (0); -                 if(Firstchildview! =NULL) { -Currenttop = Abslistview.getchildat (0). GetTop (); -}Else { +                     //when the ListView initializes, the Onscroll method is recalled, and Getchildat (0) is still empty. -                     return; +                 } A                 //determine the last visible first position and this visible first position at                 if(Firstvisibleitem! =mlastfirstpostion) { -                     //not the same location . -                     if(Firstvisibleitem >mlastfirstpostion) { -                         //under -                         if(Rg_container_resfragment.getvisibility ()! =view.gone) { - rg_container_resfragment.setvisibility (view.gone); in                         } -}Else { to                         //on +                         if(Rg_container_resfragment.getvisibility ()! =view.visible) { - rg_container_resfragment.setvisibility (view.visible); the                         } *                     } $Mlastfirsttop =Currenttop;Panax Notoginseng}Else { -                     //It's the same place . the                     if(Math.Abs (Currenttop-mlastfirsttop) >touchslop) { +                         //avoid action execution too often or wrong touch, add touchslop judgment, the specific value can be adjusted A                         if(Currenttop >mlastfirsttop) { the                             //on +                             if(Rg_container_resfragment.getvisibility ()! =view.visible) { - rg_container_resfragment.setvisibility (view.visible); $                             } $}Else if(Currenttop <mlastfirsttop) { -                             //under -                             if(Rg_container_resfragment.getvisibility ()! =view.gone) { the rg_container_resfragment.setvisibility (view.gone); -                             }Wuyi                         } theMlastfirsttop =Currenttop; -                     } Wu                 } -Mlastfirstpostion =Firstvisibleitem; About             } $});

android--to determine how the ListView slides up and down