Android: Umgang mit Wischgesten von rechts nach links

Ich möchte, dass meine App erkennt, wenn ein Benutzer auf dem Telefonbildschirm von rechts nach links wischt.

Wie macht man das?

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() {
    }
}

Verwendungszweck:

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();
    }

});

Dieser Code erkennt Wischbewegungen nach links und rechts, vermeidet veraltete API-Aufrufe und weist andere verschiedene Verbesserungen gegenüber früheren Antworten auf.

/**
 * Detects left and right swipes across a view.
 */
public class OnSwipeTouchListener implements OnTouchListener {

    private final GestureDetector gestureDetector;

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

    public void onSwipeLeft() {
    }

    public void onSwipeRight() {
    }

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

    private final class GestureListener extends SimpleOnGestureListener {

        private static final int SWIPE_DISTANCE_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) {
            float distanceX = e2.getX() - e1.getX();
            float distanceY = e2.getY() - e1.getY();
            if (Math.abs(distanceX) > Math.abs(distanceY) && Math.abs(distanceX) > SWIPE_DISTANCE_THRESHOLD && Math.abs(velocityX) > SWIPE_VELOCITY_THRESHOLD) {
                if (distanceX > 0)
                    onSwipeRight();
                else
                    onSwipeLeft();
                return true;
            }
            return false;
        }
    }
}

Verwenden Sie es wie folgt:

view.setOnTouchListener(new OnSwipeTouchListener(context) {
    @Override
    public void onSwipeLeft() {
        // Whatever
    }
});

Wenn Sie auch Klickereignisse verarbeiten müssen, hier einige Änderungen:

public class OnSwipeTouchListener implements OnTouchListener {

    private final GestureDetector gestureDetector = new GestureDetector(new GestureListener());

    public boolean onTouch(final View v, final 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 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) {
                            result = onSwipeRight();
                        } else {
                            result = onSwipeLeft();
                        }
                    }
                } else {
                    if (Math.abs(diffY) > SWIPE_THRESHOLD && Math.abs(velocityY) > SWIPE_VELOCITY_THRESHOLD) {
                        if (diffY > 0) {
                            result = onSwipeBottom();
                        } else {
                            result = onSwipeTop();
                        }
                    }
                }
            } catch (Exception exception) {
                exception.printStackTrace();
            }
            return result;
        }
    }

    public boolean onSwipeRight() {
        return false;
    }

    public boolean onSwipeLeft() {
        return false;
    }

    public boolean onSwipeTop() {
        return false;
    }

    public boolean onSwipeBottom() {
        return false;
    }
}

Und Beispielverwendung:

    background.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View arg0) {
            toggleSomething();
        }
    });
    background.setOnTouchListener(new OnSwipeTouchListener() {
        public boolean onSwipeTop() {
            Toast.makeText(MainActivity.this, "top", Toast.LENGTH_SHORT).show();
            return true;
        }
        public boolean onSwipeRight() {
            Toast.makeText(MainActivity.this, "right", Toast.LENGTH_SHORT).show();
            return true;
        }
        public boolean onSwipeLeft() {
            Toast.makeText(MainActivity.this, "left", Toast.LENGTH_SHORT).show();
            return true;
        }
        public boolean onSwipeBottom() {
            Toast.makeText(MainActivity.this, "bottom", Toast.LENGTH_SHORT).show();
            return true;
        }
    });

Erweiterung von Mireks Antwort für den Fall, dass Sie die Wischgesten in einer Bildlaufansicht verwenden möchten. Standardmäßig wird der Touch-Listener für die Scroll-Ansicht deaktiviert und daher findet keine Scroll-Aktion statt. Um dies zu beheben, müssen Sie die überschreiben dispatchTouchEvent Methode der Activity und geben Sie die geerbte Version dieser Methode zurück, nachdem Sie mit Ihrem eigenen Listener fertig sind.

Um ein paar Änderungen an Mireks Code vorzunehmen: Ich füge einen Getter für die hinzu gestureDetector in dem OnSwipeTouchListener.

public GestureDetector getGestureDetector(){
    return  gestureDetector;
}

Deklarieren Sie die OnSwipeTouchListener innerhalb der Aktivität als klassenweites Feld.

OnSwipeTouchListener onSwipeTouchListener;

Ändern Sie den Verwendungscode entsprechend:

onSwipeTouchListener = 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();
    }
});

imageView.setOnTouchListener(onSwipeTouchListener);

Und überschreibe die dispatchTouchEvent Methode drinnen Activity:

@Override
    public boolean dispatchTouchEvent(MotionEvent ev){
        swipeListener.getGestureDetector().onTouchEvent(ev); 
            return super.dispatchTouchEvent(ev);   
    }

Jetzt sollten sowohl Scroll- als auch Wischaktionen funktionieren.

Um zu haben Click Listener, DoubleClick Listener, OnLongPress Listener, Swipe Left, Swipe Right, Swipe Up, Swipe Down auf Single View du musst setOnTouchListener. dh,

view.setOnTouchListener(new OnSwipeTouchListener(MainActivity.this) {

            @Override
            public void onClick() {
                super.onClick();
                // your on click here
            }

            @Override
            public void onDoubleClick() {
                super.onDoubleClick();
                // your on onDoubleClick here
            }

            @Override
            public void onLongClick() {
                super.onLongClick();
                // your on onLongClick here
            }

            @Override
            public void onSwipeUp() {
                super.onSwipeUp();
                // your swipe up here
            }

            @Override
            public void onSwipeDown() {
                super.onSwipeDown();
                // your swipe down here.
            }

            @Override
            public void onSwipeLeft() {
                super.onSwipeLeft();
                // your swipe left here.
            }

            @Override
            public void onSwipeRight() {
                super.onSwipeRight();
                // your swipe right here.
            }
        });

}

Dazu benötigen Sie OnSwipeTouchListener Klasse, die implementiert OnTouchListener.

public class OnSwipeTouchListener implements View.OnTouchListener {

private GestureDetector gestureDetector;

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

public boolean onTouch(final View view, final MotionEvent motionEvent) {
    return gestureDetector.onTouchEvent(motionEvent);
}

private final class GestureListener extends GestureDetector.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 onSingleTapUp(MotionEvent e) {
        onClick();
        return super.onSingleTapUp(e);
    }

    @Override
    public boolean onDoubleTap(MotionEvent e) {
        onDoubleClick();
        return super.onDoubleTap(e);
    }

    @Override
    public void onLongPress(MotionEvent e) {
        onLongClick();
        super.onLongPress(e);
    }

    // Determines the fling velocity and then fires the appropriate swipe event accordingly
    @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();
                    }
                }
            } else {
                if (Math.abs(diffY) > SWIPE_THRESHOLD && Math.abs(velocityY) > SWIPE_VELOCITY_THRESHOLD) {
                    if (diffY > 0) {
                        onSwipeDown();
                    } else {
                        onSwipeUp();
                    }
                }
            }
        } catch (Exception exception) {
            exception.printStackTrace();
        }
        return result;
    }
}

public void onSwipeRight() {
}

public void onSwipeLeft() {
}

public void onSwipeUp() {
}

public void onSwipeDown() {
}

public void onClick() {

}

public void onDoubleClick() {

}

public void onLongClick() {

}
}

Die Kotlin-Version von @Mirek Rusin ist hier:

OnSwipeTouchListener.kt :

open class OnSwipeTouchListener(ctx: Context) : OnTouchListener {

    private val gestureDetector: GestureDetector

    companion object {

        private val SWIPE_THRESHOLD = 100
        private val SWIPE_VELOCITY_THRESHOLD = 100
    }

    init {
        gestureDetector = GestureDetector(ctx, GestureListener())
    }

    override fun onTouch(v: View, event: MotionEvent): Boolean {
        return gestureDetector.onTouchEvent(event)
    }

    private inner class GestureListener : SimpleOnGestureListener() {


        override fun onDown(e: MotionEvent): Boolean {
            return true
        }

        override fun onFling(e1: MotionEvent, e2: MotionEvent, velocityX: Float, velocityY: Float): Boolean {
            var result = false
            try {
                val diffY = e2.y - e1.y
                val diffX = e2.x - e1.x
                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
        }


    }

    open fun onSwipeRight() {}

    open fun onSwipeLeft() {}

    open fun onSwipeTop() {}

    open fun onSwipeBottom() {}
}

Verwendungszweck:

view.setOnTouchListener(object : OnSwipeTouchListener(context) {

    override fun onSwipeTop() {
        super.onSwipeTop()
    }

    override fun onSwipeBottom() {
        super.onSwipeBottom()
    }

    override fun onSwipeLeft() {
        super.onSwipeLeft()
    }

    override fun onSwipeRight() {
        super.onSwipeRight()
    }
})

der open Stichwort war für mich der Punkt…

Sie brauchen keine komplizierten Berechnungen. Dies kann nur durch die Verwendung erfolgen OnGestureListener Schnittstelle ab GestureDetector Klasse.

Innen onFling Methode können Sie alle vier Richtungen wie folgt erkennen:

MyGestureListener.java:

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

public class MyGestureListener implements GestureDetector.OnGestureListener{

    private static final long VELOCITY_THRESHOLD = 3000;

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

    @Override
    public void onShowPress(final MotionEvent e){ }

    @Override
    public boolean onSingleTapUp(final MotionEvent e){ return false; }

    @Override
    public boolean onScroll(final MotionEvent e1, final MotionEvent e2, final float distanceX,
                        final float distanceY){ return false; }

    @Override
    public void onLongPress(final MotionEvent e){ }

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

        if(Math.abs(velocityX) < VELOCITY_THRESHOLD 
                    && Math.abs(velocityY) < VELOCITY_THRESHOLD){
            return false;//if the fling is not fast enough then it's just like drag
        }

        //if velocity in X direction is higher than velocity in Y direction,
        //then the fling is horizontal, else->vertical
        if(Math.abs(velocityX) > Math.abs(velocityY)){
            if(velocityX >= 0){
                Log.i("TAG", "swipe right");
            }else{//if velocityX is negative, then it's towards left
                Log.i("TAG", "swipe left");
            }
        }else{
            if(velocityY >= 0){
                Log.i("TAG", "swipe down");
            }else{
                Log.i("TAG", "swipe up");
            }
        }

        return true;
    }
}

Verwendungszweck:

GestureDetector mDetector = new GestureDetector(MainActivity.this, new MyGestureListener());

view.setOnTouchListener(new View.OnTouchListener(){
    @Override
    public boolean onTouch(final View v, final MotionEvent event){
        return mDetector.onTouchEvent(event);
    }
});