android--Custom Scrolling ViewGroup

The custom control provides a getadapter and Setadapter interface for setting the view to scroll (the full screen width is displayed by default for each view)

 Public  class scrollerviewgroup extends viewgroup {    Private intScreenHeight;//the phone Screen height    Private intCurrentY;//Record the current current Y position    Private intstartscrolly;//Record the scroll position of the Y-direction when the finger presses the touch event    Private intendscrolly;//Record the scroll position of the Y-direction when the finger lifts the touch event    PrivateAdapter Madapter;//Display adapter    PrivateScroller Mscroller; Public Scrollerviewgroup(context context, AttributeSet attrs) { This(Context,NULL, attrs); } Public Scrollerviewgroup(Context context) { This(Context,NULL,NULL); } Public Scrollerviewgroup(context context, Adapter Adapter) { This(Context, adapter,NULL); } Public Scrollerviewgroup(context context, Adapter Adapter, AttributeSet attrs) { This(context, adapter, Attrs,0); } Public Scrollerviewgroup(context context, Adapter Adapter, AttributeSet attrs,intDEFSTYLEATTR) {Super(Context, attrs, defstyleattr); This. Madapter = Adapter;    Init (context); }//Initialize Mscroller and ScreenHeight    Private void Init(Context context) {Mscroller =NewScroller (context);        Displaymetrics metrics = GetContext (). Getresources (). Getdisplaymetrics ();    ScreenHeight = Metrics.heightpixels; } PublicAdapterGetadapter() {returnMadapter; } Public void Setadapter(Adapter Madapter) { This. Madapter = Madapter; }@Override    protected void onmeasure(intWidthmeasurespec,intHEIGHTMEASURESPEC) {Super. Onmeasure (Widthmeasurespec, Heightmeasurespec);if(Madapter = =NULL)return;intCount = Madapter.getcount (); for(inti =0; I < count; i++) {View child = Madapter.getview (i,NULL, This);            AddView (child);        Measurechild (Child, Widthmeasurespec, Heightmeasurespec); }    }@Override    protectedLayoutparamsGeneratelayoutparams(Viewgroup.layoutparams p) {return NewMarginlayoutparams (P); }@Override    protected void OnLayout(BooleanChangedintLintTintRintb) {intCount = Getchildcount ();        Marginlayoutparams MLP = (marginlayoutparams) getlayoutparams ();        Mlp.height = ScreenHeight * count; Setlayoutparams (MLP); for(inti =0, j =0; I < count; i++) {View child = Getchildat (i);if(child.getvisibility () = = VISIBLE)            {Child.layout (L, J * ScreenHeight, R, (++j) * screenheight); }        }    }@Override     Public Boolean ontouchevent(Motionevent event) {inty = (int) event.gety ();Switch(Event.getaction ()) { CaseMotionEvent.ACTION_DOWN:currentY = y; startscrolly = getscrolly (); Break; CaseMotionevent.action_move:if(!mscroller.isfinished ()) mscroller.abortanimation ();intoffset = currenty-y;if(Getscrolly () <0) offset =0;if(getscrolly () > GetHeight ()-screenheight) offset =0; Scrollby (0, offset); CurrentY = y; Break; CaseMotionEvent.ACTION_UP:endScrollY = getscrolly ();intOffsetY = endscrolly-startscrolly;if(OffsetY >0) {if(OffsetY > ScreenHeight/3) {Mscroller.startscroll (0, Endscrolly,0, screenheight-offsety); }Else{Mscroller.startscroll (0, Endscrolly,0,-offsety); }                }Else{if(-offsety > ScreenHeight/3) {Mscroller.startscroll (0, Endscrolly,0,-screenheight-offsety); }Else{Mscroller.startscroll (0, Endscrolly,0,-offsety); }                } Break; } postinvalidate ();return true; }@Override     Public void Computescroll() {Super. Computescroll ();if(Mscroller.computescrolloffset ()) {ScrollTo (0, Mscroller.getcurry ());        Postinvalidate (); }    }}

When used:

protected void onCreate(Bundle savedinstancestate)        {super.oncreate (savedinstancestate); Setcontentview (R.layout.activity_main); Adapter Adapter =NewArrayadapter<integer> ( This,0, color) {@Override PublicViewGetView(intPosition, View Convertview, ViewGroup parent) {intcolor = GetItem (position);if(Convertview = =NULL) {Convertview =NewView (GetContext ()); Viewgroup.layoutparamsparams=NewViewgroup.layoutparams (ViewGroup.LayoutParams.MATCH_PARENT, Viewgro Up.                    Layoutparams.match_parent); Convertview.setlayoutparams (params); } convertview.setbackgroundcolor (color);returnConvertview;        }        }; SVG = (scrollerviewgroup) Findviewbyid (r.id.svg);if(svg==NULL) LOG.E ("Main","NULL");    Svg.setadapter (adapter); } integer[] color =NewInteger[]{color.red, Color.Blue, color.yellow};

android--Custom Scrolling ViewGroup