回到上一个后面仍然加载表单中的数据

Question

我正在尝试调整和开具网络应用程序的发票，当产品订购且数量高于数据库中的数量时，它会显示错误。我写了一个后面的代码，但刷新了页面。我希望在您单击后退按钮时保留插入的数据。

            HashSet hs = new HashSet();

            hs.addAll(list); 
//list is the ArrayList<String> which contains the addressess of all the messages and 
//through hashset we remove all the duplicates to get only the addressess once and hence we know the number of conversations and their addressess.

            list.clear();
            list.addAll(hs);
             //Add some dummy message to each conversation
            ContentValues values2 = new ContentValues();
            for (int i = 0; i < list.size(); i++) {
                values2.put("address",list.get(i));
                values2.put("date_sent",readMsgsFromFile[0][1]);
                values2.put("date",readMsgsFromFile[0][2]);
                values2.put("type",readMsgsFromFile[0][3]);
                values2.put("body","temp"); //this should be more unique
                values2.put("read",readMsgsFromFile[0][5]);
                values2.put("service_center","01010101");

                contentResolver.insert(Telephony.Sms.CONTENT_URI, values2);
            }

//Now deleting that message with body 'temp' from each conversation
            Cursor c = contentResolver.query(Telephony.Sms.CONTENT_URI,null,null,null,null);
            while (c.moveToNext()){
                String body = c.getString(c.getColumnIndex("body"));
                String mid = c.getString(0);
                if (body.equals("temp")){
                    Log.i("Deleting ",mid);
                    getContentResolver().delete(Uri.parse(Telephony.Sms.CONTENT_URI+"/"+mid),null,null);
                }
            }
            c.close();