我想让飞的手势检测工作在我的Android应用程序。

我有一个GridLayout,包含9个ImageViews。来源可以在这里找到:罗曼家伙的网格布局。

我从Romain Guy的Photostream应用程序中获取的文件只做了轻微的修改。

对于简单的点击情况,我只需要为每个ImageView设置onClickListener,我添加为实现View.OnClickListener的主要活动。实现能够识别投掷的东西似乎要复杂得多。我猜这是因为它可能跨越不同的观点?

If my activity implements OnGestureListener I don't know how to set that as the gesture listener for the Grid or the Image views that I add. public class SelectFilterActivity extends Activity implements View.OnClickListener, OnGestureListener { ... If my activity implements OnTouchListener then I have no onFling method to override (it has two events as parameters allowing me to determine if the fling was noteworthy). public class SelectFilterActivity extends Activity implements View.OnClickListener, OnTouchListener { ... If I make a custom View, like GestureImageView that extends ImageView I don't know how to tell the activity that a fling has occurred from the view. In any case, I tried this and the methods weren't called when I touched the screen.

我真的需要一个跨视图工作的具体例子。我应该在什么时候以及如何附加这个侦听器?我还需要能够检测单个点击。

// Gesture detection
mGestureDetector = new GestureDetector(this, new GestureDetector.SimpleOnGestureListener() {

    public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
        int dx = (int) (e2.getX() - e1.getX());
        // don't accept the fling if it's too short
        // as it may conflict with a button push
        if (Math.abs(dx) > MAJOR_MOVE && Math.abs(velocityX) > Math.absvelocityY)) {
            if (velocityX > 0) {
                moveRight();
            } else {
                moveLeft();
            }
            return true;
        } else {
            return false;
        }
    }
});

是否有可能在我的屏幕上方放置一个透明的视图来捕捉投掷?

如果我选择不从XML膨胀我的子图像视图,我可以通过手势检测器作为构造函数参数到我创建的ImageView的新子类吗?

这是一个非常简单的活动,我试图让飞动检测工作:SelectFilterActivity(改编自photostream)。

我一直在看这些资料:

检测手势-教程 SDK文档 计算器的代码

到目前为止,什么都没用,我希望能得到一些指导。


当前回答

这里有很多很好的信息。不幸的是,许多这种抛抛处理代码以不同的完成状态分散在不同的站点上,尽管人们会认为这对许多应用程序来说是必不可少的。

我已经花时间创建了一个fling侦听器,用于验证是否满足适当的条件。我添加了一个页抛监听器,它添加了更多检查,以确保页抛满足页抛的阈值。这两个侦听器都允许您轻松地将投掷限制在水平轴或垂直轴上。你可以看到它是如何在滑动图像的视图中使用的。我承认这里的人已经做了大部分的研究——我只是把它们放在一个可用的图书馆里。

这几天是我第一次尝试在Android上编写代码;期待更多。

其他回答

我需要一个更通用的类,我采取了Tomas的类,并添加了一个接口,发送事件到您的活动或片段。 它会在构造函数上注册监听器,所以确保你实现了接口,否则就会出现ClassCastException。该接口返回定义的四个最终整型之一 并将返回激活它的视图。

import android.app.Activity;
import android.support.v4.app.Fragment;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;

public class SwipeDetector implements View.OnTouchListener{

    static final int MIN_DISTANCE = 100;
    private float downX, downY, upX, upY;
    public final static int RIGHT_TO_LEFT=1;
    public final static int LEFT_TO_RIGHT=2;
    public final static int TOP_TO_BOTTOM=3;
    public final static int BOTTOM_TO_TOP=4;
    private View v;

    private onSwipeEvent swipeEventListener;


    public SwipeDetector(Activity activity,View v){
        try{
            swipeEventListener=(onSwipeEvent)activity;
        }
        catch(ClassCastException e)
        {
            Log.e("ClassCastException",activity.toString()+" must implement SwipeDetector.onSwipeEvent");
        } 
        this.v=v;
    }
    public SwipeDetector(Fragment fragment,View v){
        try{
            swipeEventListener=(onSwipeEvent)fragment;
        }
        catch(ClassCastException e)
        {
            Log.e("ClassCastException",fragment.toString()+" must implement SwipeDetector.onSwipeEvent");
        } 
        this.v=v;
    }


    public void onRightToLeftSwipe(){   
        swipeEventListener.SwipeEventDetected(v,RIGHT_TO_LEFT);
    }

    public void onLeftToRightSwipe(){   
        swipeEventListener.SwipeEventDetected(v,LEFT_TO_RIGHT);
    }

    public void onTopToBottomSwipe(){   
        swipeEventListener.SwipeEventDetected(v,TOP_TO_BOTTOM);
    }

    public void onBottomToTopSwipe(){
        swipeEventListener.SwipeEventDetected(v,BOTTOM_TO_TOP);
    }

    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 , int SwipeType);
    }

}

上面的一个答案提到了处理不同的像素密度,但建议手动计算滑动参数。值得注意的是,你可以使用ViewConfiguration类从系统中获得合理的缩放值:

final ViewConfiguration vc = ViewConfiguration.get(getContext());
final int swipeMinDistance = vc.getScaledPagingTouchSlop();
final int swipeThresholdVelocity = vc.getScaledMinimumFlingVelocity();
final int swipeMaxOffPath = vc.getScaledTouchSlop();
// (there is also vc.getScaledMaximumFlingVelocity() one could check against)

我注意到,使用这些值可以使应用程序和系统其他部分之间的“感觉”更加一致。

我知道现在回答已经太晚了,但我仍然在发布ListView的滑动检测,如何在ListView项目中使用滑动触摸侦听器。

参考:Exterminator13(本页答案之一)

创建一个ActivitySwipeDetector.class

package com.example.wocketapp;

import android.content.Context;
import android.util.DisplayMetrics;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewConfiguration;

public class ActivitySwipeDetector implements View.OnTouchListener 
{
    static final String logTag = "SwipeDetector";
    private SwipeInterface activity;
    private float downX, downY;
    private long timeDown;
    private final float MIN_DISTANCE;
    private final int VELOCITY;
    private final float MAX_OFF_PATH;

    public ActivitySwipeDetector(Context context, SwipeInterface activity)
    {
        this.activity = activity;
        final ViewConfiguration vc = ViewConfiguration.get(context);
        DisplayMetrics dm = context.getResources().getDisplayMetrics();
        MIN_DISTANCE = vc.getScaledPagingTouchSlop() * dm.density;
        VELOCITY = vc.getScaledMinimumFlingVelocity();
        MAX_OFF_PATH = MIN_DISTANCE * 2;
    }

    public void onRightToLeftSwipe(View v) 
    {
        Log.i(logTag, "RightToLeftSwipe!");
        activity.onRightToLeft(v);
    }

    public void onLeftToRightSwipe(View v) 
    {
        Log.i(logTag, "LeftToRightSwipe!");
        activity.onLeftToRight(v);
    }

    public boolean onTouch(View v, MotionEvent event) 
    {
        switch (event.getAction()) 
        {
            case MotionEvent.ACTION_DOWN:
            {
                Log.d("onTouch", "ACTION_DOWN");
                timeDown = System.currentTimeMillis();
                downX = event.getX();
                downY = event.getY();
                v.getParent().requestDisallowInterceptTouchEvent(false);
                return true;
            }

        case MotionEvent.ACTION_MOVE:
            {
                float y_up = event.getY();
                float deltaY = y_up - downY;
                float absDeltaYMove = Math.abs(deltaY);

                if (absDeltaYMove > 60) 
                {
                    v.getParent().requestDisallowInterceptTouchEvent(false);
                } 
                else
                {
                    v.getParent().requestDisallowInterceptTouchEvent(true);
                }
            }

            break;

            case MotionEvent.ACTION_UP: 
            {
                Log.d("onTouch", "ACTION_UP");
                long timeUp = System.currentTimeMillis();
                float upX = event.getX();
                float upY = event.getY();

                float deltaX = downX - upX;
                float absDeltaX = Math.abs(deltaX);
                float deltaY = downY - upY;
                float absDeltaY = Math.abs(deltaY);

                long time = timeUp - timeDown;

                if (absDeltaY > MAX_OFF_PATH) 
                {
                    Log.e(logTag, String.format(
                            "absDeltaY=%.2f, MAX_OFF_PATH=%.2f", absDeltaY,
                            MAX_OFF_PATH));
                    return v.performClick();
                }

                final long M_SEC = 1000;
                if (absDeltaX > MIN_DISTANCE && absDeltaX > time * VELOCITY / M_SEC) 
                {
                     v.getParent().requestDisallowInterceptTouchEvent(true);
                    if (deltaX < 0) 
                    {
                        this.onLeftToRightSwipe(v);
                        return true;
                    }
                    if (deltaX > 0) 
                    {
                        this.onRightToLeftSwipe(v);
                        return true;
                    }
                }
                else 
                {
                    Log.i(logTag,
                            String.format(
                                    "absDeltaX=%.2f, MIN_DISTANCE=%.2f, absDeltaX > MIN_DISTANCE=%b",
                                    absDeltaX, MIN_DISTANCE,
                                    (absDeltaX > MIN_DISTANCE)));
                    Log.i(logTag,
                            String.format(
                                    "absDeltaX=%.2f, time=%d, VELOCITY=%d, time*VELOCITY/M_SEC=%d, absDeltaX > time * VELOCITY / M_SEC=%b",
                                    absDeltaX, time, VELOCITY, time * VELOCITY
                                            / M_SEC, (absDeltaX > time * VELOCITY
                                            / M_SEC)));
                }

                 v.getParent().requestDisallowInterceptTouchEvent(false);

            }
        }
        return false;
    }
    public interface SwipeInterface 
    {

        public void onLeftToRight(View v);

        public void onRightToLeft(View v);
    }

}

从你的activity类中调用它,就像这样:

yourLayout.setOnTouchListener(new ActivitySwipeDetector(this, your_activity.this));

别忘了实现SwipeInterface,它会给你两个@override方法:

    @Override
    public void onLeftToRight(View v) 
    {
        Log.e("TAG", "L to R");
    }

    @Override
    public void onRightToLeft(View v) 
    {
        Log.e("TAG", "R to L");
    }

如果你不喜欢创建一个单独的类或者让代码变得复杂, 你可以在OnTouchListener中创建一个GestureDetector变量,让你的代码更简单

namVyuVar可以是你需要设置监听器的视图的任何名称

namVyuVar.setOnTouchListener(new View.OnTouchListener()
{
    @Override
    public boolean onTouch(View view, MotionEvent MsnEvtPsgVal)
    {
        flingActionVar.onTouchEvent(MsnEvtPsgVal);
        return true;
    }

    GestureDetector flingActionVar = new GestureDetector(getApplicationContext(), new GestureDetector.SimpleOnGestureListener()
    {
        private static final int flingActionMinDstVac = 120;
        private static final int flingActionMinSpdVac = 200;

        @Override
        public boolean onFling(MotionEvent fstMsnEvtPsgVal, MotionEvent lstMsnEvtPsgVal, float flingActionXcoSpdPsgVal, float flingActionYcoSpdPsgVal)
        {
            if(fstMsnEvtPsgVal.getX() - lstMsnEvtPsgVal.getX() > flingActionMinDstVac && Math.abs(flingActionXcoSpdPsgVal) > flingActionMinSpdVac)
            {
                // TskTdo :=> On Right to Left fling

                return false;
            }
            else if (lstMsnEvtPsgVal.getX() - fstMsnEvtPsgVal.getX() > flingActionMinDstVac && Math.abs(flingActionXcoSpdPsgVal) > flingActionMinSpdVac)
            {
                // TskTdo :=> On Left to Right fling

                return false;
            }

            if(fstMsnEvtPsgVal.getY() - lstMsnEvtPsgVal.getY() > flingActionMinDstVac && Math.abs(flingActionYcoSpdPsgVal) > flingActionMinSpdVac)
            {
                // TskTdo :=> On Bottom to Top fling

                return false;
            }
            else if (lstMsnEvtPsgVal.getY() - fstMsnEvtPsgVal.getY() > flingActionMinDstVac && Math.abs(flingActionYcoSpdPsgVal) > flingActionMinSpdVac)
            {
                // TskTdo :=> On Top to Bottom fling

                return false;
            }
            return false;
        }
    });
});

这里有很多很好的信息。不幸的是,许多这种抛抛处理代码以不同的完成状态分散在不同的站点上,尽管人们会认为这对许多应用程序来说是必不可少的。

我已经花时间创建了一个fling侦听器,用于验证是否满足适当的条件。我添加了一个页抛监听器,它添加了更多检查,以确保页抛满足页抛的阈值。这两个侦听器都允许您轻松地将投掷限制在水平轴或垂直轴上。你可以看到它是如何在滑动图像的视图中使用的。我承认这里的人已经做了大部分的研究——我只是把它们放在一个可用的图书馆里。

这几天是我第一次尝试在Android上编写代码;期待更多。