Fling gesture detection on grid layout

Question

I want to get fling gesture detection working in my Android application   What I have is a GridLayout that contains 9 ImageViews  The source can be found here  Romain Guys s Grid Layout   That file I take is from Romain Guy s Photostream application and has only been slightly adapted   For the simple click situation I need only set the onClickListener for each ImageView I add to be the main activity which implements View OnClickListener  It seems infinitely more complicated to implement something that recognizes a fling  I presume this is because it may span views    If my activity implements OnGestureListener I don t know how to set that as the gesture listener for the Grid or the Image views that I add   public class SelectFilterActivity extends Activity implements    View OnClickListener  OnGestureListener        If my activity implements OnTouchListener then I have no onFling method to override  it has two events as parameters allowing me to determine if the fling was noteworthy    public class SelectFilterActivity extends Activity implements     View OnClickListener  OnTouchListener        If I make a custom View  like GestureImageView that extends ImageView I don t know how to tell the activity that a fling has occurred from the view  In any case  I tried this and the methods weren t called when I touched the screen    I really just need a concrete example of this working across views  What  when and how should I attach this listener  I need to be able to detect single clicks also      Gesture detection mGestureDetector   new GestureDetector this  new GestureDetector SimpleOnGestureListener          public boolean onFling MotionEvent e1  MotionEvent e2  float velocityX  float velocityY            int dx    int   e2 getX   - e1 getX                don t accept the fling if it s too short            as it may conflict with a button push         if  Math abs dx   gt  MAJOR MOVE  amp  amp  Math abs velocityX   gt  Math absvelocityY                 if  velocityX  gt  0                    moveRight                  else                   moveLeft                              return true            else               return false                        Is it possible to lay a transparent view over the top of my screen to capture flings   If I choose not to inflate my child image views from XML can I pass the GestureDetector as a constructor parameter to a new subclass of ImageView that I create   This is the very simple activity that I m trying to get the fling detection to work for  SelectFilterActivity  Adapted from photostream    I ve been looking at these sources    Detect Gestures - Tutorial SDK docs Calculator Code   Nothing has worked for me so far and I was hoping for some pointers

User · Answer

My version of solution proposed by Thomas Fankhauser and Marek Sebera (does not handle vertical swipes):

SwipeInterface.java

import android.view.View;

public interface SwipeInterface {

    public void onLeftToRight(View v);

    public void onRightToLeft(View v);
}

ActivitySwipeDetector.java

import android.content.Context;
import android.util.DisplayMetrics;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewConfiguration;

public class ActivitySwipeDetector implements View.OnTouchListener {

    static final String logTag = "ActivitySwipeDetector";
    private SwipeInterface activity;
    private float downX, downY;
    private long timeDown;
    private final float MIN_DISTANCE;
    private final int VELOCITY;
    private final float MAX_OFF_PATH;

    public ActivitySwipeDetector(Context context, SwipeInterface activity){
        this.activity = activity;
        final ViewConfiguration vc = ViewConfiguration.get(context);
        DisplayMetrics dm = context.getResources().getDisplayMetrics();
        MIN_DISTANCE = vc.getScaledPagingTouchSlop() * dm.density;
        VELOCITY = vc.getScaledMinimumFlingVelocity();
        MAX_OFF_PATH = MIN_DISTANCE * 2;            
    }

    public void onRightToLeftSwipe(View v){
        Log.i(logTag, "RightToLeftSwipe!");
        activity.onRightToLeft(v);
    }

    public void onLeftToRightSwipe(View v){
        Log.i(logTag, "LeftToRightSwipe!");
        activity.onLeftToRight(v);
    }

    public boolean onTouch(View v, MotionEvent event) {
        switch(event.getAction()){
        case MotionEvent.ACTION_DOWN: {
            Log.d("onTouch", "ACTION_DOWN");
            timeDown = System.currentTimeMillis();
            downX = event.getX();
            downY = event.getY();
            return true;
        }
        case MotionEvent.ACTION_UP: {
            Log.d("onTouch", "ACTION_UP");
            long timeUp = System.currentTimeMillis();
            float upX = event.getX();
            float upY = event.getY();

            float deltaX = downX - upX;
            float absDeltaX = Math.abs(deltaX); 
            float deltaY = downY - upY;
            float absDeltaY = Math.abs(deltaY);

            long time = timeUp - timeDown;

            if (absDeltaY > MAX_OFF_PATH) {
                Log.i(logTag, String.format("absDeltaY=%.2f, MAX_OFF_PATH=%.2f", absDeltaY, MAX_OFF_PATH));
                return v.performClick();
            }

            final long M_SEC = 1000;
            if (absDeltaX > MIN_DISTANCE && absDeltaX > time * VELOCITY / M_SEC) {
                if(deltaX < 0) { this.onLeftToRightSwipe(v); return true; }
                if(deltaX > 0) { this.onRightToLeftSwipe(v); return true; }
            } else {
                Log.i(logTag, String.format("absDeltaX=%.2f, MIN_DISTANCE=%.2f, absDeltaX > MIN_DISTANCE=%b", absDeltaX, MIN_DISTANCE, (absDeltaX > MIN_DISTANCE)));
                Log.i(logTag, String.format("absDeltaX=%.2f, time=%d, VELOCITY=%d, time*VELOCITY/M_SEC=%d, absDeltaX > time * VELOCITY / M_SEC=%b", absDeltaX, time, VELOCITY, time * VELOCITY / M_SEC, (absDeltaX > time * VELOCITY / M_SEC)));
            }

        }
        }
        return false;
    }

}

User · Answer

If you dont like to create a separate class or make code complex  You can just create a GestureDetector variable inside OnTouchListener and make your code more easier  namVyuVar can be any name of the View on which you need to set the listner  namVyuVar setOnTouchListener new View OnTouchListener          Override     public boolean onTouch View view  MotionEvent MsnEvtPsgVal                flingActionVar onTouchEvent MsnEvtPsgVal           return true             GestureDetector flingActionVar   new GestureDetector getApplicationContext    new GestureDetector SimpleOnGestureListener                 private static final int flingActionMinDstVac   120          private static final int flingActionMinSpdVac   200            Override         public boolean onFling MotionEvent fstMsnEvtPsgVal  MotionEvent lstMsnEvtPsgVal  float flingActionXcoSpdPsgVal  float flingActionYcoSpdPsgVal                        if fstMsnEvtPsgVal getX   - lstMsnEvtPsgVal getX    gt  flingActionMinDstVac  amp  amp  Math abs flingActionXcoSpdPsgVal   gt  flingActionMinSpdVac                                   TskTdo    gt  On Right to Left fling                  return false                            else if  lstMsnEvtPsgVal getX   - fstMsnEvtPsgVal getX    gt  flingActionMinDstVac  amp  amp  Math abs flingActionXcoSpdPsgVal   gt  flingActionMinSpdVac                                   TskTdo    gt  On Left to Right fling                  return false                             if fstMsnEvtPsgVal getY   - lstMsnEvtPsgVal getY    gt  flingActionMinDstVac  amp  amp  Math abs flingActionYcoSpdPsgVal   gt  flingActionMinSpdVac                                   TskTdo    gt  On Bottom to Top fling                  return false                            else if  lstMsnEvtPsgVal getY   - fstMsnEvtPsgVal getY    gt  flingActionMinDstVac  amp  amp  Math abs flingActionYcoSpdPsgVal   gt  flingActionMinSpdVac                                   TskTdo    gt  On Top to Bottom fling                  return false                            return false

User · Answer

This is a combined answer of the two answers at top  if anyone wants a working implementation   package com yourapplication   import android content Context  import android view GestureDetector  import android view MotionEvent  import android view View  import android view ViewConfiguration   public abstract class OnSwipeListener implements View OnTouchListener        private final GestureDetector gestureDetector       public OnSwipeListener Context context           gestureDetector   new GestureDetector context  new OnSwipeGestureListener context            gestureDetector setIsLongpressEnabled false               Override     public boolean onTouch View view  MotionEvent event            return gestureDetector onTouchEvent event              private final class OnSwipeGestureListener extends GestureDetector SimpleOnGestureListener            private final int minSwipeDelta          private final int minSwipeVelocity          private final int maxSwipeVelocity           private OnSwipeGestureListener Context context                ViewConfiguration configuration   ViewConfiguration get context                  We think a swipe scrolls a full page                minSwipeDelta   configuration getScaledTouchSlop                minSwipeDelta   configuration getScaledPagingTouchSlop                minSwipeVelocity   configuration getScaledMinimumFlingVelocity                maxSwipeVelocity   configuration getScaledMaximumFlingVelocity                        Override         public boolean onDown MotionEvent event                   Return true because we want system to report subsequent events to us              return true                        NOTE  see http   stackoverflow com questions 937313 android-basic-gesture-detection          Override         public boolean onFling MotionEvent event1  MotionEvent event2  float velocityX                                 float velocityY                 boolean result   false              try                   float deltaX   event2 getX   - event1 getX                    float deltaY   event2 getY   - event1 getY                    float absVelocityX   Math abs velocityX                   float absVelocityY   Math abs velocityY                   float absDeltaX   Math abs deltaX                   float absDeltaY   Math abs deltaY                   if  absDeltaX  gt  absDeltaY                        if  absDeltaX  gt  minSwipeDelta  amp  amp  absVelocityX  gt  minSwipeVelocity                              amp  amp  absVelocityX  lt  maxSwipeVelocity                            if  deltaX  lt  0                                onSwipeLeft                              else                               onSwipeRight                                                                        result   true                    else if  absDeltaY  gt  minSwipeDelta  amp  amp  absVelocityY  gt  minSwipeVelocity                          amp  amp  absVelocityY  lt  maxSwipeVelocity                        if  deltaY  lt  0                            onSwipeTop                          else                           onSwipeBottom                                                            result   true                catch  Exception e                    e printStackTrace                              return result                       public void onSwipeLeft           public void onSwipeRight           public void onSwipeTop           public void onSwipeBottom

User · Answer

One of the answers above mentions handling different pixel density but suggests computing the swipe parameters by hand  It is worth noting that you can actually obtain scaled  reasonable values from the system using ViewConfiguration class   final ViewConfiguration vc   ViewConfiguration get getContext     final int swipeMinDistance   vc getScaledPagingTouchSlop    final int swipeThresholdVelocity   vc getScaledMinimumFlingVelocity    final int swipeMaxOffPath   vc getScaledTouchSlop        there is also vc getScaledMaximumFlingVelocity   one could check against    I noticed that using these values causes the  feel  of fling to be more consistent between the application and rest of system

User · Answer

This question is kind of old and in July 2011 Google released the Compatibility Package  revision 3  which includes the ViewPager that works with Android 1 6 upwards  The GestureListener answers posted for this question don t feel very elegant on Android  If you re looking for the code used in switching between photos in the Android Gallery or switching views in the new Play Market app then it s definitely ViewPager   Here s some links for more info    http   android-developers blogspot com 2011 08 horizontal-view-swiping-with-viewpager html http   mobile tutsplus com tutorials android android-user-interface-design-horizontal-view-paging  http   thepseudocoder wordpress com 2011 10 05 android-page-swiping-using-viewpager

User · Answer

To all  don t forget about case MotionEvent ACTION CANCEL   it calls in 30  swipes without ACTION UP  and its equal to ACTION UP in this case

User · Answer

There s a built-in interface that you can use directly for all gestures  Here is an explanation for a basic level user   There is 2 imports be careful in choosing that both are diferent

User · Answer

Gestures are those subtle motions to trigger interactions between the touch screen and the user  It lasts for the time between the first touch on the screen to the point when the last finger leaves the surface    Android provides us with a class called GestureDetector using which we can detect common gestures like tapping down and up  swiping vertically and horizontally  fling   long and short press  double taps  etc  and attach listeners to them    Make our Activity class implement GestureDetector OnDoubleTapListener  for double tap gesture detection  and GestureDetector OnGestureListener interfaces and implement all the abstract methods For more info  you may visit https   developer android com training gestures detector html   Courtesy   For Demo Test GestureDetectorDemo

User · Answer

Also as a minor enhancement   The main reason for the try catch block is that e1 could be null for the initial movement   in addition to the try catch  include a test for null and return  similar to the following  if  e1    null    e2    null  return false  try         catch  Exception e     return false

User · Answer

The swipe gesture detector code above is very useful  You may however wish to make this solution density agnostic by using the following relative values  REL SWIPE  rather than the absolute values  SWIPE     DisplayMetrics dm   getResources   getDisplayMetrics     int REL SWIPE MIN DISTANCE    int  SWIPE MIN DISTANCE   dm densityDpi   160 0f   int REL SWIPE MAX OFF PATH    int  SWIPE MAX OFF PATH   dm densityDpi   160 0f   int REL SWIPE THRESHOLD VELOCITY    int  SWIPE THRESHOLD VELOCITY   dm densityDpi   160 0f

User · Answer

I know its too late to answer but Still I am posting Swipe Detection for ListView that How to use Swipe Touch Listener in ListView Item   Refrence  Exterminator13 one of answer in this page   Make one ActivitySwipeDetector class  package com example wocketapp   import android content Context  import android util DisplayMetrics  import android util Log  import android view MotionEvent  import android view View  import android view ViewConfiguration   public class ActivitySwipeDetector implements View OnTouchListener        static final String logTag    SwipeDetector       private SwipeInterface activity      private float downX  downY      private long timeDown      private final float MIN DISTANCE      private final int VELOCITY      private final float MAX OFF PATH       public ActivitySwipeDetector Context context  SwipeInterface activity                this activity   activity          final ViewConfiguration vc   ViewConfiguration get context           DisplayMetrics dm   context getResources   getDisplayMetrics            MIN DISTANCE   vc getScaledPagingTouchSlop     dm density          VELOCITY   vc getScaledMinimumFlingVelocity            MAX OFF PATH   MIN DISTANCE   2             public void onRightToLeftSwipe View v                 Log i logTag   RightToLeftSwipe             activity onRightToLeft v              public void onLeftToRightSwipe View v                 Log i logTag   LeftToRightSwipe             activity onLeftToRight v              public boolean onTouch View v  MotionEvent event                 switch  event getAction                           case MotionEvent ACTION DOWN                                Log d  onTouch    ACTION DOWN                    timeDown   System currentTimeMillis                    downX   event getX                    downY   event getY                    v getParent   requestDisallowInterceptTouchEvent false                   return true                         case MotionEvent ACTION MOVE                                float y up   event getY                    float deltaY   y up - downY                  float absDeltaYMove   Math abs deltaY                    if  absDeltaYMove  gt  60                                         v getParent   requestDisallowInterceptTouchEvent false                                      else                                       v getParent   requestDisallowInterceptTouchEvent true                                                break               case MotionEvent ACTION UP                                 Log d  onTouch    ACTION UP                    long timeUp   System currentTimeMillis                    float upX   event getX                    float upY   event getY                     float deltaX   downX - upX                  float absDeltaX   Math abs deltaX                   float deltaY   downY - upY                  float absDeltaY   Math abs deltaY                    long time   timeUp - timeDown                   if  absDeltaY  gt  MAX OFF PATH                                         Log e logTag  String format                               absDeltaY   2f  MAX OFF PATH   2f   absDeltaY                              MAX OFF PATH                        return v performClick                                       final long M SEC   1000                  if  absDeltaX  gt  MIN DISTANCE  amp  amp  absDeltaX  gt  time   VELOCITY   M SEC                                          v getParent   requestDisallowInterceptTouchEvent true                       if  deltaX  lt  0                                                 this onLeftToRightSwipe v                           return true                                            if  deltaX  gt  0                                                 this onRightToLeftSwipe v                           return true                                                          else                                        Log i logTag                              String format                                       absDeltaX   2f  MIN DISTANCE   2f  absDeltaX  gt  MIN DISTANCE  b                                       absDeltaX  MIN DISTANCE                                       absDeltaX  gt  MIN DISTANCE                         Log i logTag                              String format                                       absDeltaX   2f  time  d  VELOCITY  d  time VELOCITY M SEC  d  absDeltaX  gt  time   VELOCITY   M SEC  b                                       absDeltaX  time  VELOCITY  time   VELOCITY                                               M SEC   absDeltaX  gt  time   VELOCITY                                               M SEC                                         v getParent   requestDisallowInterceptTouchEvent false                                    return false            public interface SwipeInterface                 public void onLeftToRight View v            public void onRightToLeft View v              Call it from your activity class like this   yourLayout setOnTouchListener new ActivitySwipeDetector this  your activity this      And Don t forget to implement SwipeInterface which will give you two  override methods        Override     public void onLeftToRight View v                 Log e  TAG    L to R                Override     public void onRightToLeft View v                 Log e  TAG    R to L

User · Answer

I do it a little different  and wrote an extra detector class that implements the View onTouchListener   onCreateis simply add it to the lowest layout like this   ActivitySwipeDetector activitySwipeDetector   new ActivitySwipeDetector this   lowestLayout    RelativeLayout this findViewById R id lowestLayout   lowestLayout setOnTouchListener activitySwipeDetector     where id lowestLayout is the id xxx for the view lowest in the layout hierarchy and lowestLayout is declared as a RelativeLayout  And then there is the actual activity swipe detector class   public class ActivitySwipeDetector implements View OnTouchListener    static final String logTag    ActivitySwipeDetector   private Activity activity  static final int MIN DISTANCE   100  private float downX  downY  upX  upY   public ActivitySwipeDetector Activity activity       this activity   activity     public void onRightSwipe        Log i logTag   RightToLeftSwipe         activity doSomething       public void onLeftSwipe        Log i logTag   LeftToRightSwipe         activity doSomething       public void onDownSwipe        Log i logTag   onTopToBottomSwipe         activity doSomething       public void onUpSwipe        Log i logTag   onBottomToTopSwipe         activity doSomething       public boolean onTouch View v  MotionEvent event        switch event getAction             case MotionEvent ACTION DOWN                downX   event getX                downY   event getY                return true                    case MotionEvent ACTION UP                upX   event getX                upY   event getY                 float deltaX   downX - upX              float deltaY   downY - upY             swipe horizontal          if Math abs deltaX   gt  Math abs deltaY                         if Math abs deltaX   gt  MIN DISTANCE                      left or right                 if deltaX  gt  0    this onRightSwipe    return true                    if deltaX  lt  0    this onLeftSwipe    return true                              else                       Log i logTag   Horizontal Swipe was only     Math abs deltaX      long  need at least     MIN DISTANCE                       return false     We don t consume the event                                    swipe vertical          else                        if Math abs deltaY   gt  MIN DISTANCE                      top or down                 if deltaY  lt  0    this onDownSwipe    return true                    if deltaY  gt  0    this onUpSwipe    return true                              else                       Log i logTag   Vertical Swipe was only     Math abs deltaX      long  need at least     MIN DISTANCE                       return false     We don t consume the event                                      return true                      return false         Works really good for me

User · Answer

There is a lot of excellent information here  Unfortunately a lot of this fling-processing code is scattered around on various sites in various states of completion  even though one would think this is essential to many applications   I ve taken the time to create a fling listener that verifies that the appropriate conditions are met  I ve added a page fling listener that adds more checks to ensure that flings meet the threshold for page flings  Both of these listeners allow you to easily restrict flings to the horizontal or vertical axis  You can see how it s used in a view for sliding images  I acknowledge that the people here have done most of the research---I ve just put it together into a usable library   These last few days represent my first stab at coding on Android  expect much more to come

User · Answer

I slightly modified and repaired solution from Thomas Fankhauser  Whole system consists from two files  SwipeInterface and ActivitySwipeDetector    SwipeInterface java  import android view View   public interface SwipeInterface        public void bottom2top View v        public void left2right View v        public void right2left View v        public void top2bottom View v          Detector  import android util Log  import android view MotionEvent  import android view View   public class ActivitySwipeDetector implements View OnTouchListener        static final String logTag    ActivitySwipeDetector       private SwipeInterface activity      static final int MIN DISTANCE   100      private float downX  downY  upX  upY       public ActivitySwipeDetector SwipeInterface activity           this activity   activity             public void onRightToLeftSwipe View v           Log i logTag   RightToLeftSwipe             activity right2left v              public void onLeftToRightSwipe View v           Log i logTag   LeftToRightSwipe             activity left2right v              public void onTopToBottomSwipe View v           Log i logTag   onTopToBottomSwipe             activity top2bottom v              public void onBottomToTopSwipe View v           Log i logTag   onBottomToTopSwipe             activity bottom2top v              public boolean onTouch View v  MotionEvent event            switch event getAction             case MotionEvent ACTION DOWN                downX   event getX                downY   event getY                return true                    case MotionEvent ACTION UP                upX   event getX                upY   event getY                 float deltaX   downX - upX              float deltaY   downY - upY                  swipe horizontal              if Math abs deltaX   gt  MIN DISTANCE                      left or right                 if deltaX  lt  0    this onLeftToRightSwipe v   return true                    if deltaX  gt  0    this onRightToLeftSwipe v   return true                              else                   Log i logTag   Swipe was only     Math abs deltaX      long  need at least     MIN DISTANCE                                 swipe vertical              if Math abs deltaY   gt  MIN DISTANCE                      top or down                 if deltaY  lt  0    this onTopToBottomSwipe v   return true                    if deltaY  gt  0    this onBottomToTopSwipe v   return true                              else                   Log i logTag   Swipe was only     Math abs deltaX      long  need at least     MIN DISTANCE                   v performClick                                              return false               it is used like this   ActivitySwipeDetector swipe   new ActivitySwipeDetector this   LinearLayout swipe layout    LinearLayout  findViewById R id swipe layout   swipe layout setOnTouchListener swipe       And in implementing Activity you need to implement methods from SwipeInterface  and you can find out on which View the Swipe Event was called    Override public void left2right View v        switch v getId             case R id swipe layout                 do your stuff here         break

User · Answer

I nedded a more generic Class   I took Tomas s class and added an Interface that send events to your Activity or Fragment  it will register the listener on the constructor so be sure you implement the interface or an ClassCastException will be thorwn  the interface returns one of the four final int defined in the class and will return the view on which it was activated upon   import android app Activity  import android support v4 app Fragment  import android util Log  import android view MotionEvent  import android view View   public class SwipeDetector implements View OnTouchListener       static final int MIN DISTANCE   100      private float downX  downY  upX  upY      public final static int RIGHT TO LEFT 1      public final static int LEFT TO RIGHT 2      public final static int TOP TO BOTTOM 3      public final static int BOTTOM TO TOP 4      private View v       private onSwipeEvent swipeEventListener        public SwipeDetector Activity activity View v           try              swipeEventListener  onSwipeEvent activity                    catch ClassCastException e                        Log e  ClassCastException  activity toString     must implement SwipeDetector onSwipeEvent                       this v v            public SwipeDetector Fragment fragment View v           try              swipeEventListener  onSwipeEvent fragment                    catch ClassCastException e                        Log e  ClassCastException  fragment toString     must implement SwipeDetector onSwipeEvent                       this v v              public void onRightToLeftSwipe               swipeEventListener SwipeEventDetected v RIGHT TO LEFT              public void onLeftToRightSwipe               swipeEventListener SwipeEventDetected v LEFT TO RIGHT              public void onTopToBottomSwipe               swipeEventListener SwipeEventDetected v TOP TO BOTTOM              public void onBottomToTopSwipe            swipeEventListener SwipeEventDetected v BOTTOM TO TOP              public boolean onTouch View v  MotionEvent event            switch event getAction             case MotionEvent ACTION DOWN                downX   event getX                downY   event getY                return true                    case MotionEvent ACTION UP                upX   event getX                upY   event getY                 float deltaX   downX - upX              float deltaY   downY - upY                 HORIZONTAL SCROLL             if Math abs deltaX   gt  Math abs deltaY                                 if Math abs deltaX   gt  MIN DISTANCE                          left or right                     if deltaX  lt  0                                                 this onLeftToRightSwipe                            return true                                            if deltaX  gt  0                            this onRightToLeftSwipe                            return true                                                           else                         not long enough swipe                        return false                                                 VERTICAL SCROLL             else                                if Math abs deltaY   gt  MIN DISTANCE                          top or down                     if deltaY  lt  0                         this onTopToBottomSwipe                        return true                                             if deltaY  gt  0                        this onBottomToTopSwipe                         return true                                                          else                         not long enough swipe                        return false                                               return true                              return false            public interface onSwipeEvent               public void SwipeEventDetected View v   int SwipeType

User · Answer

You can use the droidQuery library to handle flings  clicks  long clicks  and custom events  The implementation is built on my previous answer below  but droidQuery provides a slick  simple syntax     global variables    private boolean isSwiping   false  private SwipeDetector Direction swipeDirection   null  private View v   must be instantiated before next call     swipe-handling code   with v  swipe new Function          Override     public void invoke   droidQuery  Object    params            if  params 0     SwipeDetector Direction START              isSwiping   true          else if  params 0     SwipeDetector Direction STOP                if  isSwiping                       isSwiping   false                  if  swipeDirection    null                        switch swipeDirection                            case DOWN                                    TODO  Down swipe complete  so do something                             break                          case UP                                 TODO  Up swipe complete  so do something                             break                          case LEFT                                 TODO  Left swipe complete  so do something                             break                          case RIGHT                                 TODO  Right swipe complete  so do something                             break                          default                                  break                                                                             else               swipeDirection    SwipeDetector Direction  params 0                         Original Answer  This answer uses a combination of components from the other answers here  It consists of the SwipeDetector class  which has an inner interface for listening for events  I also provide a  RelativeLayout to show how to override a View s onTouch method to allow both swipe events and other detected events  such as clicks or long clicks    SwipeDetector  package self philbrown   import android view MotionEvent  import android view View  import android view ViewConfiguration          Detect Swipes on a per-view basis  Based on original code by Thomas Fankhauser on StackOverflow com     with adaptations by other authors  see link       author Phil Brown     see  lt a href  http   stackoverflow com questions 937313 android-basic-gesture-detection  gt android-basic-gesture-detection lt  a gt      public class SwipeDetector implements View OnTouchListener                  The minimum distance a finger must travel in order to register a swipe event              private int minSwipeDistance           Maintains a reference to the first detected down touch event         private float downX  downY           Maintains a reference to the first detected up touch event         private float upX  upY           provides access to size and dimension contants        private ViewConfiguration config                  provides callbacks to a listener class for various swipe gestures              private SwipeListener listener       public SwipeDetector SwipeListener listener                this listener   listener                           inheritDoc              public boolean onTouch View v  MotionEvent event                if  config    null                            config   ViewConfiguration get v getContext                     minSwipeDistance   config getScaledTouchSlop                       switch event getAction                      case MotionEvent ACTION DOWN              downX   event getX                downY   event getY                return true          case MotionEvent ACTION UP              upX   event getX                upY   event getY                 float deltaX   downX - upX              float deltaY   downY - upY                  swipe horizontal              if Math abs deltaX   gt  minSwipeDistance                                   left or right                 if  deltaX  lt  0                                            if  listener    null                                                            listener onRightSwipe v                                   return true                                                              if  deltaX  gt  0                                            if  listener    null                                                            listener onLeftSwipe v                                   return true                                                                            swipe vertical              if Math abs deltaY   gt  minSwipeDistance                                   top or down                 if  deltaY  lt  0                                            if  listener    null                                                            listener onDownSwipe v                                   return true                                                              if  deltaY  gt  0                                            if  listener    null                                                            listener onUpSwipe v                                   return true                                                                              return false                        Provides callbacks to a registered listener for swipe events in   link SwipeDetector          author Phil Brown             public interface SwipeListener                   Callback for registering a new swipe motion from the bottom of the view toward its top             public void onUpSwipe View v               Callback for registering a new swipe motion from the left of the view toward its right             public void onRightSwipe View v               Callback for registering a new swipe motion from the right of the view toward its left             public void onLeftSwipe View v               Callback for registering a new swipe motion from the top of the view toward its bottom             public void onDownSwipe View v             Swipe Interceptor View  package self philbrown   import android content Context  import android util AttributeSet  import android view MotionEvent  import android widget RelativeLayout   import com npeinc module NPECore model SwipeDetector  import com npeinc module NPECore model SwipeDetector SwipeListener          View subclass used for handling all touches  swipes and others      author Phil Brown     public class SwipeInterceptorView extends RelativeLayout       private SwipeDetector swiper   null       public void setSwipeListener SwipeListener listener                if  swiper    null              swiper   new SwipeDetector listener              public SwipeInterceptorView Context context            super context              public SwipeInterceptorView Context context  AttributeSet attrs            super context  attrs              public SwipeInterceptorView Context context  AttributeSet attrs  int defStyle            super context  attrs  defStyle               Override     public boolean onTouchEvent MotionEvent e                boolean swipe   false  touch   false          if  swiper    null              swipe   swiper onTouch this  e           touch   super onTouchEvent e           return swipe    touch

User · Answer

There s some proposition over the web  and this page  to use ViewConfiguration getScaledTouchSlop   to have a device-scaled value for SWIPE MIN DISTANCE   getScaledTouchSlop   is intended for the  scrolling threshold  distance  not swipe  The scrolling threshold distance has to be smaller than a  swing between page  threshold distance  For example  this function returns 12 pixels on my Samsung GS2  and the examples quoted in this page are around 100 pixels   With API Level 8  Android 2 2  Froyo   you ve got getScaledPagingTouchSlop    intended for page swipe  On my device  it returns 24  pixels   So if you re on API Level  lt  8  I think  2   getScaledTouchSlop    should be the  standard  swipe threshold  But users of my application with small screens told me that it was too few    As on my application  you can scroll vertically  and change page horizontally  With the proposed value  they sometimes change page instead of scrolling

User · Answer

Thanks to Code Shogun  whose code I adapted to my situation   Let your activity implementOnClickListener as usual   public class SelectFilterActivity extends Activity implements OnClickListener      private static final int SWIPE MIN DISTANCE   120    private static final int SWIPE MAX OFF PATH   250    private static final int SWIPE THRESHOLD VELOCITY   200    private GestureDetector gestureDetector    View OnTouchListener gestureListener      Override   protected void onCreate Bundle savedInstanceState        super onCreate savedInstanceState                          Gesture detection     gestureDetector   new GestureDetector this  new MyGestureDetector         gestureListener   new View OnTouchListener           public boolean onTouch View v  MotionEvent event            return gestureDetector onTouchEvent event                          class MyGestureDetector extends SimpleOnGestureListener        Override     public boolean onFling MotionEvent e1  MotionEvent e2  float velocityX  float velocityY          try           if  Math abs e1 getY   - e2 getY     gt  SWIPE MAX OFF PATH            return false             right to left swipe         if e1 getX   - e2 getX    gt  SWIPE MIN DISTANCE  amp  amp  Math abs velocityX   gt  SWIPE THRESHOLD VELOCITY              Toast makeText SelectFilterActivity this   Left Swipe   Toast LENGTH SHORT  show              else if  e2 getX   - e1 getX    gt  SWIPE MIN DISTANCE  amp  amp  Math abs velocityX   gt  SWIPE THRESHOLD VELOCITY              Toast makeText SelectFilterActivity this   Right Swipe   Toast LENGTH SHORT  show                      catch  Exception e                nothing               return false              Override     public boolean onDown MotionEvent e          return true                Attach your gesture listener to all the views you add to the main layout      Do this for each view added to the grid imageView setOnClickListener SelectFilterActivity this    imageView setOnTouchListener gestureListener     Watch in awe as your overridden methods are hit  both the onClick View v  of the activity and the onFling of the gesture listener   public void onClick View v      Filter f    Filter  v getTag      FilterFullscreenActivity show this  input  f       The post  fling  dance is optional but encouraged

[android] Fling gesture detection on grid layout

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