Pramod, You have to look at few things: - List.contains() will tell you whether the reference to YourObject instance is held by the list - YourObject.equals() is used by List.contains() to answer *contains?* question
In your code, you don't have YourObject, that holds the model. In your case it would be Employee class. List interface: http://download.oracle.com/javase/tutorial/collections/interfaces/list.html hash and equals: http://www.ibm.com/developerworks/java/library/j-jtp05273/index.html You are into problems with Java not Andoid per se now, so not this list I'm afraid. On Wed, May 25, 2011 at 10:43 AM, pramod.deore <[email protected]> wrote: > Still I am confused How I will check whether that list contains > particular EmpId number or not? Means if there is no record for that > particular empId then I am going to create new row but if it is > present then I will only update that particulars row's value. > > > On May 25, 2:27 pm, Daniel Drozdzewski <[email protected]> > wrote: >> Pramod, >> >> you are creating new ArrayList that backs new SimpleAdapter every time >> you receive an update, hence all there is to display is only what came >> with the update. Activity should have one Adapter per ListView and >> both of those should not be re-created, but created once and the >> updated, when needed. >> >> Your ListView and Adapter are used wrongly. >> >> Please read tutorials on both of those. >> >> >> >> >> >> On Wed, May 25, 2011 at 9:46 AM, pramod.deore <[email protected]> >> wrote: >> > Yes Daniel I will try some sample code side by side but it will be >> > great if you help to solve this tragidy. Look at my code: >> >> > private BroadcastReceiver broadcastReceiver = new BroadcastReceiver() >> > { >> > @Override >> > public void onReceive(Context context, Intent intent) >> > { >> > String res = intent.getStringExtra("Response"); >> > System.out.println ("***********************************"); >> > System.out.println (res); >> >> > if (res.length() == 0) >> > { >> > //Response has not changed >> > System.out.println("value is >> > null................."); >> > } >> >> > else >> > { >> > String delims = "\\^"; >> >> > tokens = res.split(delims); >> >> > for (int i=0;i<tokens.length;i++) >> > { >> > System.out.println("At "+i+" Value is "+tokens[i]); >> > } >> >> > if (tokens[1].equalsIgnoreCase("1")) >> >> > { >> >> > //write code for empId is exist already or not? If >> > exist then >> > update row else create new row >> > showList(); >> >> > } >> >> > else >> > { >> > //Don't this record to listview >> > } >> > } >> >> > } >> > }; >> >> > public void showList() >> > { >> >> > ArrayList<HashMap<String, String>> mylist = new >> > ArrayList<HashMap<String, String>>(); >> > HashMap<String, String> map = new HashMap<String, >> > String>(); >> > map.put("EmpId", tokens[2]); >> > map.put("Name", tokens[4]); >> > map.put("MobNo", tokens[5]); >> >> > mylist.add(map); >> > // ... >> > SimpleAdapter mSchedule = new SimpleAdapter(this, >> > mylist, >> > R.layout.listcolumns, >> > new String[] {"EmpId", "Name", >> > "MobNo"}, new int[] >> > {R.id.EmpId, R.id.Name, R.id.MobNo}); >> > list.setAdapter(mSchedule); >> > } >> >> > Now using this code listview updated continously but it shows only one >> > updated record. Means suppose first record is like: >> >> > EmpId EmpName MobNo City ..... Gender >> >> > 1 Pramod 789 Nasik M >> >> > and suppose server send second record then first record is gone and >> > shows only one record as: >> >> > EmpId EmpName MobNo City ..... Gender >> >> > 1 1 Tom 456 NY M >> >> > On May 25, 1:29 pm, Daniel Drozdzewski <[email protected]> >> > wrote: >> >> Pramod, >> >> >> You have to read up on ListView and some Adapter that backs the >> >> ListView providing it with data. >> >> >> When you receive new set of data to be displayed or your data has >> >> changed, you call BaseAdapter.notifyDataSetChanged() to notify the >> >> associated ListView to redraw all visible items. >> >> >> ListView and Adapter are powerful, hence not easy to grasp at the >> >> beginning, so you have to go through some tutorial first, if you want >> >> to use them. >> >> >> On Wed, May 25, 2011 at 9:18 AM, pramod.deore <[email protected]> >> >> wrote: >> >> > Hi actually I am getting a string with some delimilater. Now using >> >> > split() I am split that response. after spliting I am getting string >> >> > array of size 40. I am not going to display all 40 fields. I will show >> >> > near about 10 fields. >> >> >> > Once again let me explain what I want: >> >> >> > Using socket connection I am receiving response from server. I want to >> >> > display this response in list. This list contains say 10 columns. >> >> > Suppose first two records as >> >> >> > EmpId EmpName MobNo City ..... Gender >> >> >> > 1 Pramod 789 Nasik M >> >> > 1 1 Tom 456 NY M >> >> >> > Now suppose next record again for EmpId 1 then other fields will >> >> > change and it will be: >> >> >> > EmpId EmpName MobNo City ..... Gender >> >> >> > 1 Deore 789 Nasik M >> >> > 1 1 Tom 456 NY M >> >> >> > Now suppose server send again some data with EmpId which is not exist >> >> > above then it must have to add this new record.And it will be >> >> >> > EmpId EmpName MobNo City ..... Gender >> >> >> > 1 Deore 789 Nasik M >> >> > 1 1 Tom 456 NY M >> >> > 45 Rob 123 XYZ M >> >> >> > Now how to achieve this? >> >> >> > On May 25, 12:33 pm, Nikolay Elenkov <[email protected]> >> >> > wrote: >> >> >> On Wed, May 25, 2011 at 4:15 PM, pramod.deore >> >> >> <[email protected]> wrote: >> >> >> >> > On May 25, 12:08 pm, Nikolay Elenkov <[email protected]> >> >> >> > wrote: >> >> >> >> On Wed, May 25, 2011 at 4:01 PM, pramod.deore >> >> >> >> <[email protected]> wrote: >> >> >> >> > Hi Ravi thanks for reply. actually it will becomes more >> >> >> >> > complicated. >> >> >> >> > Because server is sending data 2-3 times within a second And it >> >> >> >> > will >> >> >> >> > not be good idea to store data such a frequently. >> >> >> >> >> > Can somebody please provide me a guideline How I can check whether >> >> >> >> > some key (here Name ) is already exist in listview? >> >> >> >> >> If you don't have much data to deal with it, it might be easier to >> >> >> >> just replace everything and re-display. It doesn't really matter >> >> >> >> what exactly changed. >> >> >> >> > Actually I am dealing with huge data. In above code just show a >> >> >> > sample >> >> >> > of three fields but there are more than 40 fields. >> >> >> >> Why is top-posting the norm on this list? Please write your reply >> >> >> *below* >> >> >> the previous one, so it reads like a conversation. Trimming also helps. >> >> >> >> How are you going to display 40 fields in a ListView? It doesn't >> >> >> really matter >> >> >> though, you usually care if a particular row/record changed and >> >> >> update/replace >> >> >> the whole record in your model/adapter. If you want to be able replace >> >> >> a >> >> >> particular record, use some key (e.g., the employee ID) to search for >> >> >> it, >> >> >> and update/replace it.- Hide quoted text - >> >> >> >> - Show quoted text - >> >> >> > -- >> >> > You received this message because you are subscribed to the Google >> >> > Groups "Android Developers" group. >> >> > To post to this group, send email to [email protected] >> >> > To unsubscribe from this group, send email to >> >> > [email protected] >> >> > For more options, visit this group at >> >> >http://groups.google.com/group/android-developers?hl=en >> >> >> -- >> >> Daniel Drozdzewski- Hide quoted text - >> >> >> - Show quoted text - >> >> > -- >> > You received this message because you are subscribed to the Google >> > Groups "Android Developers" group. >> > To post to this group, send email to [email protected] >> > To unsubscribe from this group, send email to >> > [email protected] >> > For more options, visit this group at >> >http://groups.google.com/group/android-developers?hl=en >> >> -- >> Daniel Drozdzewski- Hide quoted text - >> >> - Show quoted text - > > -- > You received this message because you are subscribed to the Google > Groups "Android Developers" group. > To post to this group, send email to [email protected] > To unsubscribe from this group, send email to > [email protected] > For more options, visit this group at > http://groups.google.com/group/android-developers?hl=en -- Daniel Drozdzewski -- You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
