java - Android 矩形相交

Question

我非常需要你的帮助。我开发了拖放应用程序。我现在想要完成的是，当我将拖动的对象放置到放置目标时，它应该适合放置目标。这是我到目前为止尝试过的:

    ImageView img, img2, img3=null;
AbsoluteLayout aLayout;
int status = 0;


     @Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    aLayout= (AbsoluteLayout)findViewById(R.id.absLayout);

    img = (ImageView)findViewById(R.id.imageView1);
    img2 = (ImageView)findViewById(R.id.imageView2);
    img3 = (ImageView)findViewById(R.id.imageView3);

    img.setOnTouchListener(new OnTouchListener() {
        @Override
        public boolean onTouch(View v, MotionEvent event) {

            status = 1;
            Log.i("ImageStatus","1st image moved" + status);
            return false;
        }
    });

    img2.setOnTouchListener(new OnTouchListener() {
        @Override
        public boolean onTouch(View v, MotionEvent event) {

            status = 2;
            Log.i("ImageStatus","2nd image moved" + status);
            return false;
        }
    });


       aLayout.setOnTouchListener(new OnTouchListener() {
        @Override
        public boolean onTouch(View v, MotionEvent event) {
            // TODO Auto-generated method stub
            Log.i("touch", "touched here" + event);
            boolean eventConsumed = true;
            int x = (int)event.getX();
            int y = (int)event.getY();

            if(status == 1) // any event from down and move
            {
                LayoutParams lp = new LayoutParams(LayoutParams.WRAP_CONTENT,LayoutParams.WRAP_CONTENT,
                        (int)event.getX()-img.getWidth()/2,
                        (int)event.getY()-img.getHeight()/2);
                img.setLayoutParams(lp);

            } else if(status == 2){
                    LayoutParams lp = new LayoutParams(LayoutParams.WRAP_CONTENT,LayoutParams.WRAP_CONTENT,
                            (int)event.getX()-img2.getWidth()/2,
                            (int)event.getY()-img2.getHeight()/2);
                    img2.setLayoutParams(lp);
            } else {
                Log.i("Nothing", "Nothing");
            }
            if(event.getAction()==MotionEvent.ACTION_UP){

                status = 0;
                drop(v, event);

                /*
                img.setBackgroundColor(Color.TRANSPARENT);
                img2.setBackgroundColor(Color.TRANSPARENT);

                if(status == 1){
                    if (dragging) {
                        img3.getHitRect(hitRect);
                        if (hitRect.contains(x, y)){
                            setSameAbsoluteLocation(img, img3);
                            }
                        }
                } else if (status == 2){
                    if (dragging) {
                        img3.getHitRect(hitRect);
                        if (hitRect.contains(x, y)){
                            setSameAbsoluteLocation(img2, img3);
                            }
                    }
                } 
            } */
            //dragging = false; 

            }
            return true;
        }
    });

}

private void setSameAbsoluteLocation(View v1, View v2) {
    AbsoluteLayout.LayoutParams alp2 = (AbsoluteLayout.LayoutParams) v2.getLayoutParams();
    setAbsoluteLocation(v1, alp2.x, alp2.y);
}

private void setAbsoluteLocationCentered(View v, int x, int y) {
    setAbsoluteLocation(v, x - v.getWidth() / 2, y - v.getHeight() / 2);
}

private void setAbsoluteLocation(View v, int x, int y) {
    AbsoluteLayout.LayoutParams alp = (AbsoluteLayout.LayoutParams) v.getLayoutParams();
    alp.x = x;
    alp.y = y;
    v.setLayoutParams(alp);
}

private boolean checkHit(MotionEvent event, View hit){      
    Rect rhit = new Rect(hit.getLeft(), hit.getTop(), hit.getRight(), hit.getBottom());
    return rhit.contains((int)event.getRawX(), (int)event.getRawY());
}

private boolean checkHit(View v, View hit){
    Rect rv = new Rect(v.getLeft(), v.getTop(), v.getRight(), v.getBottom());
    Rect rhit = new Rect(hit.getLeft(), hit.getTop(), hit.getRight(), hit.getBottom());
    return rv.intersect(rhit);
}

private void drop(View v, MotionEvent event){
    checkHit(v, img3);
    checkHit(event, img3);
    // Do some for looping, do some other magic, do what you want
    if(status == 1){
        setSameAbsoluteLocation(img, img3);
    }
    else if (status == 2){
        setSameAbsoluteLocation(img2, img3);
    } else {
        status = 0;
    }
}

XML:

  <AbsoluteLayout 
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/absLayout" >

<ImageView
    android:id="@+id/imageView1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_x="34dp"
    android:layout_y="50dp"
    android:src="@drawable/ic_launcher" />

<ImageView
    android:id="@+id/imageView3"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_x="142dp"
    android:layout_y="328dp"
    android:src="@drawable/ic_launcher" />

<ImageView
    android:id="@+id/imageView2"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_x="101dp"
    android:layout_y="50dp"
    android:src="@drawable/ic_launcher" />

 </AbsoluteLayout>

这里的问题是，当 status 等于 1 时，第一个 img 到达放置目标，img2 也到达。我想要的只是拖动的图像应该适合放置目标。你能帮我弄清楚我在这里缺少什么吗？谢谢。

编辑:

这是我的截图

Answer 1

仅供引用，这里是一个示例，说明如何扩展和创建 View 类，然后重写 onDraw 和 onTouchEvent 方法来执行拖放操作掉落。

使用前请编辑代码以应用您的情况。

protected class DragDrop extends View {

        private PointF left = new PointF(100, 100);
        private PointF right = new PointF(100, 100);

        private PointF nextBtnPoint = new PointF(0, 0);
        private PointF postnInfoPoint = new PointF(0, 0);
        private Rect nextBtnRect = new Rect();
        private Region nextBtnRegion = new Region();
        int markerId = 0; 
        DisplayMetrics metrics = new DisplayMetrics();
        float screenScaleFactor;

        /**
         * Constructor
         * @param context
         */
        public DragDrop (Context context) {
            super(context);                                 
            setFocusable(true);
            getWindowManager().getDefaultDisplay().getMetrics(metrics);
            screenScaleFactor = metrics.density;
            Log.i("DragDrop", "Current Screen Factor: " + screenScaleFactor );

            // calculate the button position
            nextBtnPoint.x = (metrics.widthPixels - bmNextButton.getWidth())/2;
            nextBtnPoint.y = metrics.heightPixels - bmNextButton.getHeight();

            // specify a region that contains the nextbutton
            // NO NEED to add PADDINGs at the bottom, cuz this button is laid at bottom of the screen already.
            nextBtnRect = new Rect((int)nextBtnPoint.x - NEXT_BTN_PADDING, (int)nextBtnPoint.y - NEXT_BTN_PADDING, 
                    (int)nextBtnPoint.x + (int)bmNextButton.getWidth() + NEXT_BTN_PADDING, (int)nextBtnPoint.y + (int)bmNextButton.getHeight());

            nextBtnRegion = new Region(nextBtnRect);


        }

        @Override
        protected void onDraw(Canvas canvas) {

            canvas.drawBitmap(bmBackground, 0, 0, null);

            canvas.drawBitmap(bmLeft, markers[0].getX(), markers[0].getY(), null);
            canvas.drawBitmap(bmRight, markers[1].getX(), markers[1].getY(), null);


            // draw position info and next button
            canvas.drawBitmap(bmNextButton, nextBtnPoint.x, nextBtnPoint.y, null);

            canvas.drawBitmap(bmPositionInfo, postnInfoPoint.x, postnInfoPoint.y, null);


        }

        public boolean onTouchEvent(MotionEvent e) {

            float x = e.getX();
            float y = e.getY();

            switch (e.getAction()) {

            case MotionEvent.ACTION_DOWN:

                // if the touch is outside the next button, then go on to response the normal touch event
                if(!nextBtnRegion.contains((int)x, (int)y)) {


                    }


                } else {
                            // Touch inside the area
                }
                break;

            case MotionEvent.ACTION_MOVE:
                // ACTION_MOVE need to detect if the point is in Next Button
                if(markers[markerId].isTouched && !nextBtnRegion.contains((int)x, (int)y)) {


                    switch (markerId) {
                    //left touched
                    case 0:
                        markers[markerId].setX(x + markers[markerId].getDistF().x);
                        // move the markers up for 100px so that users can see where they are moving
                        markers[markerId].setY(y - bmLeft.getHeight() - 50 * metrics.density + markers[markerId].getDistF().y);
                        break;

                    //right touched
                    case 1:
                        markers[markerId].setX(x + markers[markerId].getDistF().x);
                        markers[markerId].setY(y - bmRight.getHeight() - 50 * metrics.density + markers[markerId].getDistF().y);                        
                        break;


                    }
                }


                break;
            }

            // redraw the canvas
            invalidate();
            return true;

        }