How to detect the swipe left or Right in Android?

Question

I have a edittext view in android. On this I want to detect a swipe left or right. I am able to get it on a empty space with the below code. But this does not work when I swipe on a edittext. How do i do it? Please let me know If I am doing something wrong. Thank you.

Code Used

    switch (touchevent.getAction())

    {
        case MotionEvent.ACTION_DOWN:
        {
            oldTouchValue = touchevent.getX();
            break;
        }
        case MotionEvent.ACTION_UP:
        {
            float currentX = touchevent.getX();
            if (oldTouchValue < currentX)
            {
                // swiped left
            }
            if (oldTouchValue > currentX )
            {
                swiped right
            }
        break;
        }
    }

Answer 1

I like the code from @user2999943. But just some minor changes for my own purposes.

@Override
public boolean onTouchEvent(MotionEvent event)
{     
    switch(event.getAction())
    {
      case MotionEvent.ACTION_DOWN:
          x1 = event.getX();                         
      break;         
      case MotionEvent.ACTION_UP:
          x2 = event.getX();
          float deltaX = x2 - x1;

          if (Math.abs(deltaX) > MIN_DISTANCE)
          {
              // Left to Right swipe action
              if (x2 > x1)
              {
                  Toast.makeText(this, "Left to Right swipe [Next]", Toast.LENGTH_SHORT).show ();                     
              }

              // Right to left swipe action               
              else 
              {
                  Toast.makeText(this, "Right to Left swipe [Previous]", Toast.LENGTH_SHORT).show ();                    
              }

          }
          else
          {
              // consider as something else - a screen tap for example
          }                          
      break;   
    }           
    return super.onTouchEvent(event);       
}

Answer 2

Simplest left to right swipe detector:

In your activity class add following attributes:

private float x1,x2;
static final int MIN_DISTANCE = 150;

and override onTouchEvent() method:

@Override
public boolean onTouchEvent(MotionEvent event)
{     
    switch(event.getAction())
    {
      case MotionEvent.ACTION_DOWN:
          x1 = event.getX();                          
      break;          
      case MotionEvent.ACTION_UP:
          x2 = event.getX();
          float deltaX = x2 - x1;
          if (Math.abs(deltaX) > MIN_DISTANCE)
          {
              Toast.makeText(this, "left2right swipe", Toast.LENGTH_SHORT).show ();
          }
          else
          {
              // consider as something else - a screen tap for example
          }                       
      break;    
    }            
    return super.onTouchEvent(event);        
}

Answer 3

I think what you want is called a fling. The MotionEvents can be used to determine the direction of the fling.

public class MainActivity extends Activity implements  GestureDetector.OnGestureListener {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.stellar_layout);
        mDetector = new GestureDetectorCompat(this, this);
    }

    @Override
    public boolean onFling(MotionEvent event1, MotionEvent event2,
                           float velocityX, float velocityY) {
        Log.d(tag, "onFling:\n " + event1.toString()+ "\n " + event2.toString());
        /* prints the following
            MotionEvent { action=ACTION_DOWN, id[0]=0, x[0]=297.0, y[0]=672.0, toolType[0]=TOOL_TYPE_FINGER, buttonState=0, metaState=0, flags=0x0, edgeFlags=0x0, pointerCount=1, historySize=0, eventTime=488341979, downTime=488341979, deviceId=6, source=0x1002 }
            MotionEvent { action=ACTION_UP, id[0]=0, x[0]=560.0, y[0]=583.0, toolType[0]=TOOL_TYPE_FINGER, buttonState=0, metaState=0, flags=0x0, edgeFlags=0x0, pointerCount=1, historySize=0, eventTime=488342047, downTime=488341979, deviceId=6, source=0x1002 }
        */
        return true;
    }

}

http://developer.android.com/training/gestures/detector.html

Answer 4

public class TransferMarket extends Activity {

    float x1,x2;
    float y1, y2;

    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_transfer_market);
    }

    // onTouchEvent () method gets called when User performs any touch event on screen

    // Method to handle touch event like left to right swap and right to left swap

    public boolean onTouchEvent(MotionEvent touchevent)
    {
        switch (touchevent.getAction())
        {
            // when user first touches the screen we get x and y coordinate
            case MotionEvent.ACTION_DOWN:
            {
                x1 = touchevent.getX();
                y1 = touchevent.getY();
                break;
            }
            case MotionEvent.ACTION_UP:
            {
                x2 = touchevent.getX();
                y2 = touchevent.getY();

                //if left to right sweep event on screen
                if (x1 < x2)
                {
                    Toast.makeText(this, "Left to Right Swap Performed", Toast.LENGTH_LONG).show();
                }

                // if right to left sweep event on screen
                if (x1 > x2)
                {
                    Toast.makeText(this, "Right to Left Swap Performed", Toast.LENGTH_LONG).show();
                }

                // if UP to Down sweep event on screen
                if (y1 < y2)
                {
                    Toast.makeText(this, "UP to Down Swap Performed", Toast.LENGTH_LONG).show();
                }

                //if Down to UP sweep event on screen
                if (y1 > y2)
                {
                    Toast.makeText(this, "Down to UP Swap Performed", Toast.LENGTH_LONG).show();
                }
                break;
            }
        }
        return false;
    }

Answer 5

This is a cute class I use (in cases I want to catch event on a View, if it is a ViewGroup, I use the second implementation):

import android.util.Log;
import android.view.MotionEvent;
import android.view.View;

public class SwipeDetector implements View.OnTouchListener{

    private int min_distance = 100;
    private float downX, downY, upX, upY;
    private View v;

    private onSwipeEvent swipeEventListener;



    public SwipeDetector(View v){
        this.v=v;
        v.setOnTouchListener(this);
    }

    public void setOnSwipeListener(onSwipeEvent listener)
    {
        try{
            swipeEventListener=listener;
        }
        catch(ClassCastException e)
        {
            Log.e("ClassCastException","please pass SwipeDetector.onSwipeEvent Interface instance",e);
        }
    }


    public void onRightToLeftSwipe(){
        if(swipeEventListener!=null)
            swipeEventListener.SwipeEventDetected(v,SwipeTypeEnum.RIGHT_TO_LEFT);
        else
            Log.e("SwipeDetector error","please pass SwipeDetector.onSwipeEvent Interface instance");
    }

    public void onLeftToRightSwipe(){
        if(swipeEventListener!=null)
            swipeEventListener.SwipeEventDetected(v,SwipeTypeEnum.LEFT_TO_RIGHT);
        else
            Log.e("SwipeDetector error","please pass SwipeDetector.onSwipeEvent Interface instance");
    }

    public void onTopToBottomSwipe(){
        if(swipeEventListener!=null)
            swipeEventListener.SwipeEventDetected(v,SwipeTypeEnum.TOP_TO_BOTTOM);
        else
            Log.e("SwipeDetector error","please pass SwipeDetector.onSwipeEvent Interface instance");
    }

    public void onBottomToTopSwipe(){
        if(swipeEventListener!=null)
            swipeEventListener.SwipeEventDetected(v,SwipeTypeEnum.BOTTOM_TO_TOP);
        else
            Log.e("SwipeDetector error","please pass SwipeDetector.onSwipeEvent Interface instance");
    }

    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) > Math.abs(deltaY))
            {
                if(Math.abs(deltaX) > min_distance){
                    // left or right
                    if(deltaX < 0) 
                    {
                        this.onLeftToRightSwipe();
                        return true;
                    }
                    if(deltaX > 0) {
                        this.onRightToLeftSwipe();
                        return true; 
                    }
                }
                else {
                    //not long enough swipe...
                    return false; 
                }
            }
            //VERTICAL SCROLL
            else 
            {
                if(Math.abs(deltaY) > min_distance){
                    // top or down
                    if(deltaY < 0) 
                    { this.onTopToBottomSwipe();
                    return true; 
                    }
                    if(deltaY > 0)
                    { this.onBottomToTopSwipe(); 
                    return true;
                    }
                }
                else {
                    //not long enough swipe...
                    return false;
                }
            }

            return true;
        }
        }
        return false;
    }
    public interface onSwipeEvent
    {
        public void SwipeEventDetected(View v, SwipeTypeEnum SwipeType);
    }

    public SwipeDetector setMinDistanceInPixels(int min_distance)
{
    this.min_distance=min_distance;
    return this;
}

    public enum SwipeTypeEnum
    {
        RIGHT_TO_LEFT,LEFT_TO_RIGHT,TOP_TO_BOTTOM,BOTTOM_TO_TOP
    }

}

and this is a use example:

filters_container=(RelativeLayout)root.findViewById(R.id.filters_container);
    new SwipeDetector(filters_container).setOnSwipeListener(new SwipeDetector.onSwipeEvent() {
        @Override
        public void SwipeEventDetected(View v, SwipeDetector.SwipeTypeEnum swipeType) {
            if(swipeType==SwipeDetector.SwipeTypeEnum.LEFT_TO_RIGHT)
                getActivity().onBackPressed();
        }
    });

---

In some cases you would like to detect the swipe gestures on a container and pass down the touch Events to the childs so in that case you can create a Custom View group, lets say RelativeLayout and override onInterceptTouchEvent , and there you can detect the swipe event without blocking the pass of Touch Event to your child views,for Example:

    import android.content.Context;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.widget.RelativeLayout;


public class SwipeDetectRelativeLayout extends RelativeLayout {


    private float x1,x2;
    static final int MIN_DISTANCE=150;
    private onSwipeEventDetected mSwipeDetectedListener;


    public SwipeDetectRelativeLayout(Context context) {
        super(context);
    }

    public SwipeDetectRelativeLayout(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    public SwipeDetectRelativeLayout(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
    }

    @Override
    public boolean onInterceptTouchEvent(MotionEvent ev) {

        switch(ev.getAction())
        {
            case MotionEvent.ACTION_DOWN:
                x1 = ev.getX();
                break;
            case MotionEvent.ACTION_UP:
                x2 = ev.getX();
                float deltaX = x2 - x1;
                if (Math.abs(deltaX) > MIN_DISTANCE)
                {
                        //swiping right to left
                        if(deltaX<0)
                        {
                            if(mSwipeDetectedListener!=null)
                                mSwipeDetectedListener.swipeEventDetected();
                        }
                }
                break;
        }
        return super.onInterceptTouchEvent(ev);
    }

    public interface onSwipeEventDetected
    {
        public void swipeEventDetected();
    }

    public void registerToSwipeEvents(onSwipeEventDetected listener)
    {
        this.mSwipeDetectedListener=listener;
    }
}

Answer 6

Left to Right and Right to Left Swipe Detector

Firstly, declare two variable of float datatype.

private float x1, x2;

Secondly, wireup your xml view in java. Like I have ImageView

ImageView img = (ImageView) findViewById(R.id.imageView);

Thirdly, setOnTouchListener on your ImageView.

img.setOnTouchListener(
                    new View.OnTouchListener() {
                    @Override
                    public boolean onTouch(View v, MotionEvent event) {
                        // TODO Auto-generated method stub
                        switch (event.getAction()) {
                        case MotionEvent.ACTION_DOWN:
                            x1 = event.getX();
                            break;
                        case MotionEvent.ACTION_UP:
                            x2 = event.getX();
                            float deltaX = x2 - x1;
                            if (deltaX < 0) {
                                Toast.makeText(MainActivity.this,
                                        "Right to Left swipe",
                                        Toast.LENGTH_SHORT).show();
                            }else if(deltaX >0){
                                Toast.makeText(MainActivity.this,
                                        "Left to Right swipe",
                                        Toast.LENGTH_SHORT).show();
                            }
                            break;
                        }

                        return false;
                    }
                });