通过点击事件，把被叠住的View顶部（类似z-index）

一、布局文件相关定义

二、相关java代码（仅事件方法）

public void iv1click(View view)
{
	ViewGroup vg = (ViewGroup)view.getParent();
	int index = vg.indexOfChild(view);
	vg.bringChildToFront(vg.getChildAt(index));
	vg.invalidate();
}
public void iv2click(View view)
{
	ViewGroup vg = (ViewGroup)view.getParent();
	int index = vg.indexOfChild(view);
	vg.bringChildToFront(vg.getChildAt(index));
	vg.invalidate();
}
public void iv3click(View view)
{
	ViewGroup vg = (ViewGroup)view.getParent();
	int index = vg.indexOfChild(view);
	vg.bringChildToFront(vg.getChildAt(index));
	vg.invalidate();
}
public void iv4click(View view)
{
	ViewGroup vg = (ViewGroup)view.getParent();
	int index = vg.indexOfChild(view);
	vg.bringChildToFront(vg.getChildAt(index));
	vg.invalidate();
}