昨晚仿IOS彈出相機相簿的彈窗寫了個popupwindow，本來的意願是從底部彈出，但事與願違，在小米手機上不管怎麼調都是從中間彈出來，華為手機上能正常顯示出來，氣煞我也，原始碼如下：

 View parent = getActivity().findViewById(android.R.id.content);
        final View popView = View.inflate(getActivity(), R.layout.more_option_item, null);
        showAnimation(popView);//開啟動畫
        PopupWindow mPopWindow = new PopupWindow(popView, LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.WRAP_CONTENT, false);
        mPopWindow.setBackgroundDrawable(new ColorDrawable(Color.TRANSPARENT));
        mPopWindow.showAtLocation(parent, Gravity.BOTTOM | Gravity.CENTER_HORIZONTAL, 0, 0);
        mPopWindow.setOutsideTouchable(true);
        mPopWindow.setFocusable(true);
        mPopWindow.update();
        // 設定背景顏色變暗
        WindowManager.LayoutParams lp = getActivity().getWindow().getAttributes();
        lp.alpha = 0.7f;
        getActivity().getWindow().setAttributes(lp);
        mPopWindow.setOnDismissListener(new PopupWindow.OnDismissListener() {
            @Override
            public void onDismiss() {
                WindowManager.LayoutParams lp = getActivity().getWindow().getAttributes();
                lp.alpha = 1f;
                getActivity().getWindow().setAttributes(lp);
            }
        });
 

經過一番查驗之後發現只是mPopWindow.update();的影響，註釋掉就好了，關於popupwindow的update方法自行百度查一下吧，剛發現的坑，先記錄一下。