//PopupWindow布局
item_popup = View.inflate(this, R.layout.item_popup, null);
//当前布局
view = View.inflate(this, R.layout.activity_main, null);

popupWindow = new PopupWindow(inflate, ActionBar
        .LayoutParams.MATCH_PARENT,ActionBar.LayoutParams
        .WRAP_CONTENT,true);
popupWindow.setTouchable(true);

//PopupWindow布局控件
btn_daizhi = item_popup.findViewById(R.id.btn_daizhi);
btn_yizhi = item_popup.findViewById(R.id.btn_yizhi);
btn_yiqu = item_popup.findViewById(R.id.btn_yiqu);
btn_daizhi.setOnClickListener(this);
btn_yizhi.setOnClickListener(this);
btn_yiqu.setOnClickListener(this);

popupWindow.setOutsideTouchable(true);
popupWindow.setBackgroundDrawable(
        new BitmapDrawable());

image_btn.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        //点击按钮PopupWindow布局显示的位置
        //popupWindow.showAtLocation(view, Gravity.BOTTOM,0,0);
        popupWindow.showAsDropDown(image_btn);
    }
});