Android – 创建一个锚定到视图的Toast

public void onClick(View v) {
   int xOffset = 0;
   int yOffset = 0;
   Rect gvr = new Rect();

  View parent = (View) v.getParent();// v is the image,//parent is the rectangle holding it.

  if (parent.getGlobalVisibleRect(gvr)) {
        Log.v("image left",Integer.toString(gvr.left));
    Log.v("image right",Integer.toString(gvr.right));
    Log.v("image top",Integer.toString(gvr.top));
    Log.v("image bottom",Integer.toString(gvr.bottom));
    View root = v.getRootView();

        int halfwayWidth = root.getright() / 2;
        int halfwayHeight = root.getBottom() / 2;
          //get the horizontal center
    int parentCenterX = ((gvr.right - gvr.left) / 2) + gvr.left;
     //get the vertical center
    int parentCenterY = (gvr.bottom - gvr.top) / 2 + gvr.top;

    if (parentCenterY <= halfwayHeight) {
       yOffset = -(halfwayHeight - parentCenterY);//this image is    above the center of gravity,i.e. the halfwayHeight
        } else {
        yOffset = parentCenterY - halfwayHeight;
        }
    if (parentCenterX < halfwayWidth) { //this view is left of center             xOffset = -(halfwayWidth - parentCenterX);    }   if (parentCenterX >= halfwayWidth) {
       //this view is right of center
       xOffset = parentCenterX - halfwayWidth;
    }
     }
       Toast toast = Toast.makeText(activity,altText,Toast.LENGTH_SHORT);
       toast.setGravity(Gravity.CENTER,xOffset,yOffset);
       toast.show();
       }
});