Android 如何在不抬起手指的情况下检测刷卡事件

我想在连续向上/向下滑动事件中增加/减少一个数字。 我可以使用GestureDetector和OnSwipeTouchListener实现简单的滑动事件

但是，只有在刷卡后抬起手指时，才会感测到此刷卡事件。 因此，为了将数字增加到+5，我必须在屏幕上进行5次单独的向上滑动

我想应用类似“滑块”的动作，这样当用户在屏幕上任意位置上下滑动时，数字就会改变。（我不想使用“滑块”小部件）

这可能吗

任何帮助都会非常感激。

---

谢谢

使用OnTouchListener：

private float baseX, baseY;

OnTouchListener listener = new OnTouchListener(){
    public boolean onTouch (View v, MotionEvent event)
    {
        switch(event.getAction())
        {
            case MotionEvent.ACTION_DOWN:
                //TOUCH STARTED
                baseX = event.getX();
                baseY = event.getY();
                return true;
            case MotionEvent.ACTION_MOVE:
                //FINGER IS MOVING
                //Do your calculations here, using the x and y positions relative to the starting values you get in ACTION_DOWN
                return true;
            case MotionEvent.ACTION_CANCEL:
            case MotionEvent.ACTION_UP:
                //TOUCH COMPLETED
                return true;
        }
    }
}

---

@1up，非常感谢您提供的解决方案

我可以添加的一个增强功能是，即使在不抬起手指的情况下反转滑动方向，也会很好地工作

使用您提供的框架，发布我的代码，希望它能在将来帮助某人

public class OnSwipeListener implements OnTouchListener
{
    @Override
    public boolean onTouch(View v, MotionEvent event) 
    {
    boolean result = false;

    float currentX      = 0.0f;
    float currentY      = 0.0f;

    float current_diffX = 0.0f;
    float current_diffY = 0.0f;

    switch(event.getAction())
    {
        case MotionEvent.ACTION_DOWN:
            //Touch detected, record base X-Y coordinates
            baseX = event.getX();
            baseY = event.getY();

            //As the event is consumed, return true
            result = true;  
            break;

        case MotionEvent.ACTION_MOVE:
            //Swipe started, get current X-Y coordinates and compute those with the base ones
            currentX = event.getX();
            currentY = event.getY();

            current_diffX = currentX - baseX;
            current_diffY = currentY - baseY;

            //...................................................Determine horizontal swipe direction
            if(h_swipe == LEFT_SWIPE)
            {
                if( currentX > previousX )
                {
                    //If here, then horizontal swipe has been reversed
                    h_swipe = RIGHT_SWIPE;

                    //Overwrite base coordinate
                    baseX = previousX;

                    //Recalculate Difference
                    current_diffX = currentX - baseX;
                }
                else
                {
                    //NOP - Intentionally kept empty
                }
            }
            else if(h_swipe == RIGHT_SWIPE)
            {
                if( currentX < previousX )
                {
                    //If here, then horizontal swipe has been reversed
                    h_swipe = LEFT_SWIPE;

                    //Overwrite base coordinate
                    baseX = previousX;

                    //Recalculate Difference
                    current_diffX = currentX - baseX;
                }
                else
                {
                    //NOP - Intentionally kept empty
                }                   
            }
            else
            {
                //If here, then it's a fresh swipe event, so compare with base coordinates
                if( currentX < baseX )
                {
                    h_swipe = LEFT_SWIPE;
                }
                else if( currentX > baseX )
                {
                    h_swipe = RIGHT_SWIPE;
                }
                else
                {
                    //NOP - Intentionally kept empty
                }
            }

            //...................................................Determine vertical swipe direction 
            if(v_swipe == UP_SWIPE)
            {
                if(currentY > previousY)
                {
                    //If here, then vertical swipe has been reversed
                    v_swipe = DOWN_SWIPE;

                    //Overwrite base coordinate
                    baseY = previousY;

                    //Recalculate coordinate difference
                    current_diffY = currentY - baseY;
                }
                else
                {
                    //NOP - Intentionally kept empty
                }
            }
            else if(v_swipe == DOWN_SWIPE)
            {
                if(currentY < previousY)
                {
                    //If here, then vertical swipe has been reversed
                    v_swipe = UP_SWIPE;

                    //Overwrite base coordinate
                    baseY = previousY;

                    //Recalculate coordinate difference
                    current_diffY = currentY - baseY;
                }
                else
                {
                    //NOP - Intentionally kept empty
                }
            }
            else
            {
                //If here, then it's a fresh swipe event, so compare with base coordinates
                if( currentY < baseY )
                {
                    v_swipe = UP_SWIPE;
                }
                else if( currentY > baseY )
                {
                    v_swipe = DOWN_SWIPE;
                }
                else
                {
                    //NOP - Intentionally kept empty
                }
            }

            //Record current coordinates for future comparisons
            previousX = currentX;
            previousY = currentY;

            //................................Determine the prominent swipe (horizontal/vertical)
            if(Math.abs(current_diffX) > Math.abs(current_diffY))
            {
                //It's a horizontal swipe
                if (Math.abs(current_diffX) > SWIPE_THRESHOLD) 
                {
                    if (current_diffX > 0) 
                    {
                        onRightSwipe();
                    } 
                    else 
                    {
                        onLeftSwipe();
                    }
                }
                else
                {
                    //Not enough swipe movement, ignore.
                    //NOP - Intentionally kept empty
                }
            }
            else
            {
                //It's a vertical swipe
                if (Math.abs(current_diffY) > SWIPE_THRESHOLD) 
                {
                    if (current_diffY > 0) 
                    {
                        onDownSwipe();
                    } 
                    else 
                    {
                        onUpSwipe();
                    }
                }
                else
                {
                    //Not enough swipe movement, ignore.
                    //NOP - Intentionally kept empty
                }                   
            }

            //As the event is consumed, return true
            result = true;
            break;

        case MotionEvent.ACTION_UP:
            //Swipe ended, clear variables, if necessary
            h_swipe = NO_H_SWIPE;
            v_swipe = NO_V_SWIPE;

            baseX = 0.0f;
            baseY = 0.0f;

            previousX = 0.0f;
            previousY = 0.0f;

            //As the event is consumed, return true
            result = true;              
            break;

        default:

            //Do not consume event
            result = false;
            break;
    }

    return result;
}


public void onUpSwipe()
{

}

public void onDownSwipe()
{

}

public void onRightSwipe()
{

}

public void onLeftSwipe()
{

}
}

公共类OnSwipeListener实现OnTouchListener
{
@凌驾
公共布尔onTouch（视图v，运动事件）
{
布尔结果=假；
浮动电流X=0.0f；
浮动电流Y=0.0f；
浮动电流_diffX=0.0f；
浮动电流_diffY=0.0f；
开关（event.getAction（））
{
case MotionEvent.ACTION\u DOWN：
//检测到触摸，记录基本X-Y坐标
baseX=event.getX（）；
baseY=event.getY（）；
//当事件被消耗时，返回true
结果=真；
打破
case MotionEvent.ACTION\u移动：
//开始滑动，获取当前的X-Y坐标，并使用基准坐标计算这些坐标
currentX=event.getX（）；
currentY=event.getY（）；
电流_diffX=电流x-基准x；
current_diffY=currentY-baseY；
//确定水平滑动方向
如果（h_滑动==左滑动）
{
如果（当前X>上一个X）
{
//如果在此处，则水平滑动已反转
h_滑动=右滑动；
//覆盖基准坐标
baseX=上一个x；
//重新计算差额
电流_diffX=电流x-基准x；
}
其他的
{
//否-故意保持为空
}
}
else if（h_滑动==右滑动）
{
如果（当前x<先前x）
{
//如果在此处，则水平滑动已反转
h_滑动=左滑动；
//覆盖基准坐标
baseX=上一个x；
//重新计算差额
电流_diffX=电流x-基准x；
}
其他的
{
//否-故意保持为空
}                   
}
其他的
{
//如果在这里，那么它是一个新的刷卡事件，所以与基本坐标比较
如果（电流xbaseX）
{
h_滑动=右滑动；
}
其他的
{
//否-故意保持为空
}
}
//确定垂直滑动方向
如果（v_滑动==向上滑动）
{
如果（当前>以前）
{
//如果在此处，则垂直滑动已反转
v_滑动=向下滑动；
//覆盖基准坐标
baseY=先前的；
//重新计算坐标差
current_diffY=currentY-baseY；
}
其他的
{
//否-故意保持为空
}
}
否则如果（v_滑动==向下滑动）
{
如果（当前<先前）
{
//如果在此处，则垂直滑动已反转
v_滑动=向上滑动；
//覆盖基准坐标
baseY=先前的；
//重新计算坐标差
current_diffY=currentY-baseY；
}
其他的
{
//否-故意保持为空
}
}
其他的
{
//如果在这里，那么它是一个新的刷卡事件，所以与基本坐标比较
如果（当前Y<基本Y）
{
v_滑动=向上滑动；
}
否则如果（当前Y>基本Y）
{
v_滑动=向下滑动；
}
其他的
{
//否-故意保持为空
}
}
//记录当前坐标以备将来比较
previousX=当前X；
先前的y=当前的y；
//确定突出的侧击（水平/垂直）
if（Math.abs（current_diffX）>Math.abs（current_diffY））
{
//这是横扫
if（Math.abs（current\u diffX）>滑动阈值）
{
如果（当前_diffX>0）
{
onRightSwipe（）；
} 
其他的
{
onleftsweep（）；
}
}
其他的
import android.view.MotionEvent;
import android.view.View;

public class SwipeDirectionListener implements View.OnTouchListener {

float deltaX ;
float deltaY ;
float maxValX;
float maxValY;
float firstTouchX;
float firstTouchY;
float currentX ;
float currentY ;
float SWIPE_THRESHOLD = 10.0f;

@Override
public boolean onTouch(View v, MotionEvent event) {
    boolean result ;

    switch (event.getAction()) {
        case MotionEvent.ACTION_DOWN:
            //Register the first touch on TouchDown and this should not change unless finger goes up.
            firstTouchX = event.getX();
            firstTouchY = event.getY();
            maxValX = 0.0f;
            maxValY = 0.0f;
            //As the event is consumed, return true
            result = true;
            break;

        case MotionEvent.ACTION_MOVE:
            //CurrentX/Y are the continues changing values of one single touch session. Change
            //when finger slides on view
            currentX = event.getX();
            currentY = event.getY();
           //setting the maximum value of X or Y so far. Any deviation in this means a  change of direction so reset the firstTouch value to last known max value i.e MaxVal X/Y.
            if(maxValX <currentX){
                maxValX = currentX;
            }else{
                firstTouchX= maxValX;
                maxValX =0.0f;
            }

            if(maxValY <currentY){
                maxValY = currentY;
            }else{
                firstTouchY= maxValY;
                maxValY =0.0f;
            }
            //DeltaX/Y are the difference between current touch and the value when finger first touched screen.
            //If its negative that means current value is on left side of first touchdown value i.e Going left and
            //vice versa.
            deltaX = currentX - firstTouchX;
            deltaY = currentY - firstTouchY;

            if (Math.abs(deltaX) > Math.abs(deltaY)) {
                //Horizontal swipe
                if (Math.abs(deltaX) > SWIPE_THRESHOLD) {
                    if (deltaX > 0) {
                        //means we are going right
                        onRightSwipe(currentX);
                    } else {
                        //means we are going left
                        onLeftSwipe(currentX);
                    }
                } 
            } else {
                //It's a vertical swipe
                if (Math.abs(deltaY) > SWIPE_THRESHOLD) {
                    if (deltaY > 0) {
                        //means we are going down
                        onDownSwipe(currentY);
                    } else {
                        //means we are going up
                        onUpSwipe(currentY);
                    }
                } 
            }

            result = true;
            break;

        case MotionEvent.ACTION_UP:
            //Clean UP
            firstTouchX = 0.0f;
            firstTouchY = 0.0f;

            result = true;
            break;

        default:
            result = false;
            break;
    }

    return result;
}


public void onUpSwipe(float value) {

}

public void onDownSwipe(float value) {

}

public void onRightSwipe(float value) {

}

public void onLeftSwipe(float value) {

}
}

yourView.setOnTouchListener(new SwipeDirectionListener() {
        public void onUpSwipe(float value) {

            mTextView.setText("onUpSwipe :"+value);
        }

        public void onDownSwipe(float value) {
            mTextView.setText("onDownSwipe :"+value);
        }

        public void onRightSwipe(float value) {
            mTextView.setText("onRightSwipe :"+value);
        }

        public void onLeftSwipe(float value) {
            mTextView.setText("onLeftSwipe :"+value);
        }
    });