Android Multi-Touch

public class mainactivity extends activity implements ontouchlistener {//   Zoom Out Matrix matrix = new matrix (); Matrix savedmatrix = new matrix (); Pointf start = new pointf (); Pointf mid = new pointf (); float olddist;private imageview myimageview;//   Mode static final int none = 0;static final int drag = 1; static final int zoom = 2;int mode = none; @Overridepublic  void  oncreate (bundle savedinstancestate)  {super.oncreate (savedinstancestate); SetContentView ( R.layout.main);myimageview =  (ImageView)  findviewbyid (r.id.iv_image); Myimageview.setontouchlistener (this);} @Overridepublic  boolean ontouch (view v, motionevent event)  {ImageView  myimageview =  (ImageView)  v;switch  (event.getaction () &nbsP;& motionevent.action_mask)  {//  Set drag mode case motionevent.action_down:log.i ("point",   "Action_pointer_down"); Matrix.set (Myimageview.getimagematrix ()); Savedmatrix.set (matrix); Start.set ( Event.getx (),  event.gety ());mode = drag;break;case motionevent.action_up:case  motionevent.action_pointer_up:mode = none;break;//  setting Multi-touch mode Case motionevent.action_pointer _down:olddist = spacing (Event);if  (olddist > 10f)  {savedmatrix.set (matrix); Midpoint (mid, event); mode = zoom;} break;//  if it is DRAG mode, click Move Picture case motionevent.action_move:if  (Mode == drag)  { Matrix.set (Savedmatrix); Matrix.posttranslate (Event.getx ()  - start.x, event.gety ()  -  START.Y);}   If zoom mode, tap Touch zoom else if  (mode == zoom)  {float newDist =  Spacing (event);if  (newdist > 10f)  {matrix.set (Savedmatrix); float scale = newdist / olddist;//  set the zoom ratio and the midpoint position of the picture Matrix.postscale (scale, scale,  MID.X, MID.Y);}} break;} Myimageview.setimagematrix (matrix); return true;}   Calculate moving distance private float spacing (motionevent event)  {float x =  Event.getx (0)  - event.getx (1), float y = event.gety (0)  - event.gety (1); RETURN FLOATMATH.SQRT (x * x + y * y);}   Calculate midpoint position Private void midpoint (pointf point, motionevent event)  {float  x = event.getx (0)  + event.getx (1); float y = event.gety (0)  +  event.gety (1);p oint.set (X / 2, Y / 2);}}

<?xml version= "1.0" encoding= "Utf-8"? ><linearlayout xmlns:android= "http://schemas.android.com/apk/res/     Android "Android:layout_width=" Match_parent "android:layout_height=" match_parent "android:orientation=" vertical " Android:background= "@android: Color/black" > <imageview android:id= "@+id/iv_image" android:layout _width= "Wrap_content" android:layout_height= "wrap_content" android:scaletype= "Matrix" android:src= "@d Rawable/koala "/></linearlayout>

Android Multi-Touch