Android:如何处理从右向左滑动手势

我希望我的应用程序能够识别用户在手机屏幕上从右向左滑动。

如何做到这一点?

当前回答

因为这个问题有点老，很流行，我试图更新答案，并通过结合答案和评论中的多种建议来改进它。

从Java切换到Kotlin并使用一些Kotlin语法Eyecandy(主观) 使onswipe函数返回它们是否消耗了事件(ruX答案) 从if语句中移除结果赋值并删除变量(直接返回) 仅检测垂直和水平滑动的替代方案只能检测上、下、右、左的选择。为保持一致性(方向，而不是位置)，将上下重命名为上下。

四个方向都刷:

open class OnSwipeTouchListener(val context: Context?) : OnTouchListener {
    companion object {
        private const val SwipeThreshold = 100
        private const val SwipeVelocityThreshold = 100
    }

    private val gestureDetector = GestureDetector(context, GestureListener())

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

    open fun onSwipeRight(): Boolean { return false }
    open fun onSwipeLeft(): Boolean { return false }
    open fun onSwipeUp(): Boolean { return false }
    open fun onSwipeDown(): Boolean { return false }

    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 {
            try {
                val diffY = e2.y - e1.y
                val diffX = e2.x - e1.x

                if (abs(diffX) > abs(diffY)) {
                    if (abs(diffX) > SwipeThreshold && abs(velocityX) > SwipeVelocityThreshold) {
                        return when {
                            diffX > 0 -> onSwipeRight()
                            else -> onSwipeLeft()
                        }
                    }
                } else if (abs(diffY) > SwipeThreshold && abs(velocityY) > SwipeVelocityThreshold) {
                    return when {
                        diffY > 0 -> onSwipeDown()
                        else -> onSwipeUp()
                    }
                }
            } catch (exception: Exception) {
                exception.printStackTrace()
            }
            return false
        }
    }
}

用法:

myView.setOnTouchListener(object : OnSwipeTouchListener(context) {
            // Implement any function you need:
            override fun onSwipeUp(): Boolean {
                Toast.makeText(context, "UP", Toast.LENGTH_SHORT).show()
                return true
            }

            override fun onSwipeLeft(): Boolean {
                Toast.makeText(context, "LEFT", Toast.LENGTH_SHORT).show()
                return true
            }
        })

onFling()的替代方案

替代方案删除更多代码并重新排序检查。重新排序是没有必要的，但我认为它看起来更整洁，更容易理解。代码将放在try括号中。用法保持不变，只是实现各自的onSwipe函数

水平

val diffY = e2。Y - e1。Y 返回if (abs(velocityY) > SwipeVelocityThreshold) { 当{ > SwipeThreshold -> onSwipeDown() diffY < - swipethreshold -> onSwipeUp() Else -> false ｝ }其他false

垂直

val diffX = e2。X - e1。X 返回if (abs(velocityX) > SwipeVelocityThreshold) { 当{ > SwipeThreshold -> onSwipeRight() diffX < - swipethreshold -> onSwipeLeft() Else -> false ｝ }其他false

一个方向

"up"的例子

val diffY = e2。Y - e1。Y 返回{ diffY < - swipethreshold -> onSwipeUp() Else -> false ｝

Additional Notes: In (ruX answer) they discussed removing onDown to also detect an onClickListener for the same view. However, when I removed onDown, the class did not work anymore. I don't exactly know why. I looked into the code of GestureDetector but it is very complex and the consequences of the return value of onDown seems to have some implications. So I left it in. Also, you can just use SimpleOnGestureListener.onSingleTapUp() just like you did onFling and create a onClick() function that is called there.

版本信息:

compileSdkVersion 31 minSdkVersion 24 targetSdkVersion 31

2022-06-17 18:38:51

其他回答

我的解决方案与上述类似，但我将手势处理抽象为一个抽象类OnGestureRegisterListener.java，其中包括滑动、单击和长按手势。

OnGestureRegisterListener.java

public abstract class OnGestureRegisterListener implements View.OnTouchListener {

    private final GestureDetector gestureDetector;
    private View view;

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

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

    public abstract void onSwipeRight(View view);
    public abstract void onSwipeLeft(View view);
    public abstract void onSwipeBottom(View view);
    public abstract void onSwipeTop(View view);
    public abstract void onClick(View view);
    public abstract boolean onLongClick(View view);

    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 void onLongPress(MotionEvent e) {
            onLongClick(view);
            super.onLongPress(e);
        }

        @Override
        public boolean onSingleTapUp(MotionEvent e) {
            onClick(view);
            return super.onSingleTapUp(e);
        }

        @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(view);
                        } else {
                            onSwipeLeft(view);
                        }
                        result = true;
                    }
                }
                else if (Math.abs(diffY) > SWIPE_THRESHOLD && Math.abs(velocityY) > SWIPE_VELOCITY_THRESHOLD) {
                    if (diffY > 0) {
                        onSwipeBottom(view);
                    } else {
                        onSwipeTop(view);
                    }
                    result = true;
                }
            } catch (Exception exception) {
                exception.printStackTrace();
            }
            return result;
        }

    }
}

像这样使用它。注意，您还可以轻松地传入您的View参数。

OnGestureRegisterListener onGestureRegisterListener = new OnGestureRegisterListener(this) {
    public void onSwipeRight(View view) {
        // Do something
    }
    public void onSwipeLeft(View view) {
        // Do something
    }
    public void onSwipeBottom(View view) {
        // Do something
    }
    public void onSwipeTop(View view) {
        // Do something
    }
    public void onClick(View view) {
        // Do something
    }
    public boolean onLongClick(View view) { 
        // Do something
        return true;
    }
};

Button button = findViewById(R.id.my_button);
button.setOnTouchListener(onGestureRegisterListener);

2018-08-02 08:28:57

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

/**
 * Detects left and right swipes across a view.
 */
class OnSwipeTouchListener(context: Context, onSwipeCallBack: OnSwipeCallBack?) : OnTouchListener {

    private var gestureDetector : GestureDetector
    private var onSwipeCallBack: OnSwipeCallBack?=null

    init {

        gestureDetector = GestureDetector(context, GestureListener())
        this.onSwipeCallBack = onSwipeCallBack!!
    }
    companion object {

        private val SWIPE_DISTANCE_THRESHOLD = 100
        private val SWIPE_VELOCITY_THRESHOLD = 100
    }

   /* fun onSwipeLeft() {}

    fun onSwipeRight() {}*/

    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(eve1: MotionEvent?, eve2: MotionEvent?, velocityX: Float, velocityY: Float): Boolean {
            try {
                if(eve1 != null&& eve2!= null) {
                    val distanceX = eve2?.x - eve1?.x
                    val distanceY = eve2?.y - eve1?.y
                    if (Math.abs(distanceX) > Math.abs(distanceY) && Math.abs(distanceX) > SWIPE_DISTANCE_THRESHOLD && Math.abs(velocityX) > SWIPE_VELOCITY_THRESHOLD) {
                        if (distanceX > 0)
                            onSwipeCallBack!!.onSwipeLeftCallback()
                        else
                            onSwipeCallBack!!.onSwipeRightCallback()
                        return true
                    }
                }
            }catch (exception:Exception){
                exception.printStackTrace()
            }

            return false
        }


    }
}

2018-06-13 11:39:34

这段代码检测左右滑动，避免了废弃的API调用，并对之前的答案进行了其他改进。

/**
 * 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;
        }
    }
}

像这样使用它:

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

2013-10-21 22:33:19

这个问题很多年前就有人问过了。现在，有一个更好的解决方案:SmartSwipe: https://github.com/luckybilly/SmartSwipe

代码如下所示:

SmartSwipe.wrap(contentView)
        .addConsumer(new StayConsumer()) //contentView stay while swiping with StayConsumer
        .enableAllDirections() //enable directions as needed
        .addListener(new SimpleSwipeListener() {
            @Override
            public void onSwipeOpened(SmartSwipeWrapper wrapper, SwipeConsumer consumer, int direction) {
                //direction: 
                //  1: left
                //  2: right
                //  4: top
                //  8: bottom
            }
        })
;

2019-07-25 10:01:33