Android: How to Handle Right to Left Swipe Gestures

Android: How to handle right to left swipe gestures

OnSwipeTouchListener.java:

import android.content.Context;
import android.view.GestureDetector;
import android.view.GestureDetector.SimpleOnGestureListener;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;

public class OnSwipeTouchListener implements OnTouchListener {

private final GestureDetector gestureDetector;

public OnSwipeTouchListener (Context ctx){
gestureDetector = new GestureDetector(ctx, new GestureListener());
}

@Override
public boolean onTouch(View v, MotionEvent event) {
return gestureDetector.onTouchEvent(event);
}

private final class GestureListener extends SimpleOnGestureListener {

private static final int SWIPE_THRESHOLD = 100;
private static final int SWIPE_VELOCITY_THRESHOLD = 100;

@Override
public boolean onDown(MotionEvent e) {
return true;
}

@Override
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
boolean result = false;
try {
float diffY = e2.getY() - e1.getY();
float diffX = e2.getX() - e1.getX();
if (Math.abs(diffX) > Math.abs(diffY)) {
if (Math.abs(diffX) > SWIPE_THRESHOLD && Math.abs(velocityX) > SWIPE_VELOCITY_THRESHOLD) {
if (diffX > 0) {
onSwipeRight();
} else {
onSwipeLeft();
}
result = true;
}
}
else if (Math.abs(diffY) > SWIPE_THRESHOLD && Math.abs(velocityY) > SWIPE_VELOCITY_THRESHOLD) {
if (diffY > 0) {
onSwipeBottom();
} else {
onSwipeTop();
}
result = true;
}
} catch (Exception exception) {
exception.printStackTrace();
}
return result;
}
}

public void onSwipeRight() {
}

public void onSwipeLeft() {
}

public void onSwipeTop() {
}

public void onSwipeBottom() {
}
}

Usage:

imageView.setOnTouchListener(new OnSwipeTouchListener(MyActivity.this) {
public void onSwipeTop() {
Toast.makeText(MyActivity.this, "top", Toast.LENGTH_SHORT).show();
}
public void onSwipeRight() {
Toast.makeText(MyActivity.this, "right", Toast.LENGTH_SHORT).show();
}
public void onSwipeLeft() {
Toast.makeText(MyActivity.this, "left", Toast.LENGTH_SHORT).show();
}
public void onSwipeBottom() {
Toast.makeText(MyActivity.this, "bottom", Toast.LENGTH_SHORT).show();
}

});

Android Right and Left Swipe Gestures handling

scrollView.setOnTouchListener(new View.OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
switch(event.getAction()){
case MotionEvent.ACTION_DOWN:{
downX = event.getX();}
case MotionEvent.ACTION_UP:{
upX = event.getX();

float deltaX = downX - upX;

if(Math.abs(deltaX)>0){
if(deltaX>=0){
swipeToRight();
return true;
}else{
swipeToLeft();
return true;
}
}
}
}

return false;
}
});

Detect swipe gestures and touch events on a view

I found a solution.

In OnSwipeTouchListener.java:

public class OnSwipeTouchListener implements View.OnTouchListener {

private final GestureDetector gestureDetector;

public OnSwipeTouchListener(Context context) {
gestureDetector = new GestureDetector(context, new GestureListener());
}

public void onSwipeLeft() {
}

public void onSwipeRight() {
}

public void onSwipeBottom() {
}

public void onSwipeTop() {
}

public void onDownTouch() {

}

public boolean onTouch(View v, MotionEvent event) {
return gestureDetector.onTouchEvent(event);
}

private final class GestureListener extends GestureDetector.SimpleOnGestureListener {

private static final int SWIPE_DISTANCE_THRESHOLD = 100;
private static final int SWIPE_VELOCITY_THRESHOLD = 100;

@Override
public boolean onDown(MotionEvent e) {
onDownTouch();
return false;
}

@Override
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
boolean result = false;
try {
float diffY = e2.getY() - e1.getY();
float diffX = e2.getX() - e1.getX();
if (Math.abs(diffX) > Math.abs(diffY)) {
if (Math.abs(diffX) > SWIPE_DISTANCE_THRESHOLD && Math.abs(velocityX) > SWIPE_VELOCITY_THRESHOLD) {
if (diffX > 0) {
onSwipeRight();
} else {
onSwipeLeft();
}
result = true;
}
}
else if (Math.abs(diffY) > SWIPE_DISTANCE_THRESHOLD && Math.abs(velocityY) > SWIPE_VELOCITY_THRESHOLD) {
if (diffY > 0) {
onSwipeBottom();
} else {
onSwipeTop();
}
result = true;
}
} catch (Exception exception) {
exception.printStackTrace();
}
return result;
}
}

}

And in activity:

To detect button release press: (on click)

public void timerButtonPressed(View view) {

}

To detect swipes and down press:

timerButton.setOnTouchListener(new OnSwipeTouchListener(timerActivity.this) {

public void onSwipeLeft() {

}

public void onSwipeRight() {

}

public void onSwipeBottom() {

}

public void onSwipeTop() {

}

public void onDownTouch() {

}
});

How to detect swipe direction between left/right and up/down

I wrote a simple class for this: it's well documented so I wont explain it here

public class OnSwipeListener extends GestureDetector.SimpleOnGestureListener {

@Override
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {

// Grab two events located on the plane at e1=(x1, y1) and e2=(x2, y2)
// Let e1 be the initial event
// e2 can be located at 4 different positions, consider the following diagram
// (Assume that lines are separated by 90 degrees.)
//
//
// \ A /
// \ /
// D e1 B
// / \
// / C \
//
// So if (x2,y2) falls in region:
// A => it's an UP swipe
// B => it's a RIGHT swipe
// C => it's a DOWN swipe
// D => it's a LEFT swipe
//

float x1 = e1.getX();
float y1 = e1.getY();

float x2 = e2.getX();
float y2 = e2.getY();

Direction direction = getDirection(x1,y1,x2,y2);
return onSwipe(direction);
}

/** Override this method. The Direction enum will tell you how the user swiped. */
public boolean onSwipe(Direction direction){
return false;
}

/**
* Given two points in the plane p1=(x1, x2) and p2=(y1, y1), this method
* returns the direction that an arrow pointing from p1 to p2 would have.
* @param x1 the x position of the first point
* @param y1 the y position of the first point
* @param x2 the x position of the second point
* @param y2 the y position of the second point
* @return the direction
*/
public Direction getDirection(float x1, float y1, float x2, float y2){
double angle = getAngle(x1, y1, x2, y2);
return Direction.fromAngle(angle);
}

/**
*
* Finds the angle between two points in the plane (x1,y1) and (x2, y2)
* The angle is measured with 0/360 being the X-axis to the right, angles
* increase counter clockwise.
*
* @param x1 the x position of the first point
* @param y1 the y position of the first point
* @param x2 the x position of the second point
* @param y2 the y position of the second point
* @return the angle between two points
*/
public double getAngle(float x1, float y1, float x2, float y2) {

double rad = Math.atan2(y1-y2,x2-x1) + Math.PI;
return (rad*180/Math.PI + 180)%360;
}


public enum Direction{
up,
down,
left,
right;

/**
* Returns a direction given an angle.
* Directions are defined as follows:
*
* Up: [45, 135]
* Right: [0,45] and [315, 360]
* Down: [225, 315]
* Left: [135, 225]
*
* @param angle an angle from 0 to 360 - e
* @return the direction of an angle
*/
public static Direction fromAngle(double angle){
if(inRange(angle, 45, 135)){
return Direction.up;
}
else if(inRange(angle, 0,45) || inRange(angle, 315, 360)){
return Direction.right;
}
else if(inRange(angle, 225, 315)){
return Direction.down;
}
else{
return Direction.left;
}

}

/**
* @param angle an angle
* @param init the initial bound
* @param end the final bound
* @return returns true if the given angle is in the interval [init, end).
*/
private static boolean inRange(double angle, float init, float end){
return (angle >= init) && (angle < end);
}
}
}

To use simply extend the OnSwipeListener and override the onSwipe method

Detecting swipes, click, hold on one View Android

Gesture Detector is the way to go.

Alternatively,

 image.setOnTouchListener(new View.OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {

switch (event.getAction()) {

case MotionEvent.ACTION_DOWN:
x1 = event.getX();
y1 = event.getY();
t1 = System.currentTimeMillis();
return true;
case MotionEvent.ACTION_UP:
x2 = event.getX();
y2 = event.getY();
t2 = System.currentTimeMillis();

if (x1 == x2 && y1 == y2 && (t2 - t1) < CLICK_DURATION) {
Toast.makeText(getActivity(), "Click", Toast.LENGTH_SHORT).show();
} else if ((t2 - t1) >= CLICK_DURATION) {
Toast.makeText(getActivity(), "Long click", Toast.LENGTH_SHORT).show();
} else if (x1 > x2) {
Toast.makeText(getActivity(), "Left swipe", Toast.LENGTH_SHORT).show();
} else if (x2 > x1) {
Toast.makeText(getActivity(), "Right swipe", Toast.LENGTH_SHORT).show();
}


return true;
}

return false;
}

Repopulate recycleview data on left-right swipe gesture

ItemTouchHelper will not help in this case, since i want to use swipe for whole list, so i found the following solution helpful to implement the desired feature that i wanted without need to use viewpager.

His solution helped solve my problem. https://stackoverflow.com/a/50969707/3952885



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