PopupWindow如何在Android开发中使用

//创建一个包含自定义view的PopupWindowprivate PopupWindow makePopupWindow(Context cx) {  PopupWindow window;  window = new PopupWindow(cx);  TextView contentView = new TextView(cx);  contentView.setGravity(Gravity.CENTER);  final Resources res = cx.getResources();  // contentView.setBackgroundColor(R.color.page_window_bgcolor);  // window.setBackgroundDrawable(new  // ColorDrawable(res.getColor(R.color.page_window_bgcolor)));  contentView.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT,      LayoutParams.WRAP_CONTENT));  //设置PopupWindow显示和隐藏时的动画  window.setAnimationStyle(R.style.AnimationFade);  //设置PopupWindow的大小（宽度和高度）  window.setWidth(res.getDimensionPixelSize(R.dimen.page_window_width));  window.setHeight(res.getDimensionPixelSize(R.dimen.page_window_height));  //设置PopupWindow的内容view  window.setContentView(contentView);    //设置PopupWindow外部区域是否可触摸    window.setOutsideTouchable(true);  return window;}