Android Sliding Puzzzle Game: the slide effect -

i'm trying make android puzzle game out of picture. i've done 'till is: -i've cut picture in how many parts edittext field; -i've put cut pictures in gridview , got puzzle table; -i've used collection.suffle(list) suffle images in gridview;

now, trying implement sliding effect on 2 images gridview. want achieve sliding effect similar candycrush app or 1 http://www.youtube.com/watch?v=quop87fnb8w . mean, want hold image , drag top should slide top. if click picture , slide bottom, should change picture below , on...

here code:

        reset = (button) findviewbyid(r.id.breset);     splitno = (edittext) findviewbyid(r.id.edsplitby);     splitby = integer.parseint(splitno.gettext().tostring());     imgno = splitby * splitby;     puzzle = (gridview) findviewbyid(r.id.puzzle);     rootimg = (imageview) findviewbyid(r.id.source_image);     splitimage(rootimg);     formpuzzle(smallimages);     reset.setonclicklistener(new onclicklistener() {          public void onclick(view v) {             reset.settext("reset");             splitno.geteditabletext().tostring();             splitby = integer.parseint(splitno.gettext().tostring());             imgno = splitby * splitby;             collections.shuffle(smallimages);             formpuzzle(smallimages);         }      }); 

and here how form puzzle:

private void formpuzzle(arraylist<puzzleitem> smallimages) {      smi = new smallimageadapter(this, smallimages);     puzzle.setadapter(smi);     puzzle.setnumcolumns(splitby);     puzzle.sethorizontalspacing(0);     puzzle.setverticalspacing(0); } 

puzzleitem.class:

public class puzzleitem { bitmap puzzlepartimage; int correctposition;  public puzzleitem(bitmap d, int index) {     puzzlepartimage = d;     correctposition = index; } 

i used class remember position of pieces can check if puzzle finished...

so i'm interested in how implement sliding motion draging item gridview...

thanks :)

edit: should use ontouchlistener ?

ok, i've managed find solution myself :

private void formpuzzle(final arraylist<puzzleitem> smallimages) {      smi = new smallimageadapter(this, smallimages);     puzzle.setadapter(smi);     puzzle.setnumcolumns(splitby);     puzzle.sethorizontalspacing(0);     puzzle.setverticalspacing(0);      puzzle.setontouchlistener(new ontouchlistener() {          @override         public boolean ontouch(view v, motionevent event) {             switch (event.getaction()) {             case motionevent.action_down: {                 startx = event.getx();                 starty = event.gety();                 smallimage_position = puzzle.pointtoposition((int) startx,                         (int) starty);                 return true;             }             case motionevent.action_move: {                 endx = event.getx();                 endy = event.gety();                 log.d("x", "..." +endx);                 log.d("y", "..." +endy);                 if(endx > startx + smallimage_width/2 && (endy < starty - smallimage_height/2 || endy < starty + smallimage_height/2) ){                     puzzleitem p1 = smi.smallimages.get(smallimage_position);                     puzzleitem p2 = smi.smallimages.get(smallimage_position +1);                     smi.smallimages.set(smallimage_position, p2);                     smi.smallimages.set(smallimage_position +1, p1);                     smi.notifydatasetchanged();                     startx = endx*200;                     starty = endy*200;                   }                 return true;             }             }             return true;         }     }); 

the slide given motionevent.action_move , calculating pixels can find out in direction finger moving ... example .. if action_move case recognising swipe right ...

i hope of guys ...