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

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
            }
        })
;

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);

If you want to display some buttons with actions when an list item is swipe are a lot of libraries on the internet that have this behavior. I implemented the library that I found on the internet and I am very satisfied. It is very simple to use and very quick. I improved the original library and I added a new click listener for item click. Also I added font awesome library (http://fortawesome.github.io/Font-Awesome/) and now you can simply add a new item title and specify the icon name from font awesome.

这是github的链接

扩展Mirek的回答,当你想在滚动视图中使用滑动手势时。默认情况下,滚动视图的触摸监听器被禁用,因此滚动动作不会发生。为了解决这个问题,您需要重写Activity的dispatchTouchEvent方法,并在您完成自己的侦听器后返回该方法的继承版本。

为了对Mirek的代码做一些修改: 我在OnSwipeTouchListener中添加了一个gestureDetector getter。

public GestureDetector getGestureDetector(){
    return  gestureDetector;
}

在Activity中声明OnSwipeTouchListener作为类范围的字段。

OnSwipeTouchListener onSwipeTouchListener;

相应修改用法代码:

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);

并覆盖活动内部的dispatchTouchEvent方法:

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

现在滚动和滑动动作都可以工作了。

这是一个简单的Android代码,用于检测手势方向

在MainActivity.java和activity_main.xml中编写如下代码:

MainActivity.java

import java.util.ArrayList;

import android.app.Activity;
import android.gesture.Gesture;
import android.gesture.GestureLibraries;
import android.gesture.GestureLibrary;
import android.gesture.GestureOverlayView;
import android.gesture.GestureOverlayView.OnGesturePerformedListener;
import android.gesture.GestureStroke;
import android.gesture.Prediction;
import android.os.Bundle;
import android.widget.Toast;

public class MainActivity extends Activity implements
        OnGesturePerformedListener {

    GestureOverlayView gesture;
    GestureLibrary lib;
    ArrayList<Prediction> prediction;

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

        lib = GestureLibraries.fromRawResource(MainActivity.this,
                R.id.gestureOverlayView1);
        gesture = (GestureOverlayView) findViewById(R.id.gestureOverlayView1);
        gesture.addOnGesturePerformedListener(this);
    }

    @Override
    public void onGesturePerformed(GestureOverlayView overlay, Gesture gesture) {
        ArrayList<GestureStroke> strokeList = gesture.getStrokes();
        // prediction = lib.recognize(gesture);
        float f[] = strokeList.get(0).points;
        String str = "";

        if (f[0] < f[f.length - 2]) {
            str = "Right gesture";
        } else if (f[0] > f[f.length - 2]) {
            str = "Left gesture";
        } else {
            str = "no direction";
        }
        Toast.makeText(getApplicationContext(), str, Toast.LENGTH_LONG).show();

    }

}

activity_main.xml

<android.gesture.GestureOverlayView xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    xmlns:android1="http://schemas.android.com/apk/res/android"
    xmlns:android2="http://schemas.android.com/apk/res/android"
    android:id="@+id/gestureOverlayView1"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android1:orientation="vertical" >

    <TextView
        android:id="@+id/textView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Draw gesture"
        android:textAppearance="?android:attr/textAppearanceMedium" />

</android.gesture.GestureOverlayView>
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
        }


    }
}