Hi Mark, I think I got it now :)
Thanks a bunch for all your help. Regards. On Jul 1, 2008, at 4:19 PM, Mark Murphy wrote: > >> Can you please also clarify what do you mean by "use the same >> instance >> as the convertView" parameter? Dont I need a new View instance for >> every cell being displayed? i.e., if displaying 5 TextView rows at >> the >> same time, then do we need need 5 different instances of TextView? OR >> is it the case that the getView() method is called only when the View >> is about to be drawn and therefore a single instance will suffice for >> displaying the whole list ? > > Ideally, Android and your activity will only create as many row > Views as > can be physically displayed by the ListView. > > Suppose you have an Adapter that wraps a set of 50 objects, but the > ListView only has room to show 7 of those at a time. When your > activity > launches, I believe your Adapter will have getView() called 7 times > with a > null convertView, which you will wind up populating with the first 7 > objects' data out of the 50 available objects. Then, if the user > scrolls > the ListView, your getView() will start being called with convertView > sometimes being non-null, meaning the ListView wants to fill in an > existing row's View with new data. > > I imagine the precise details on when getView() will be called with a > possible-to-recycle convertView will vary as Android evolves. > However, if > you get a non-null convertView, Android is asking you to recycle > that View > if possible. Either return convertView (after modifying the contents > to > reflect the data identified by the supplied position), or return a > brand-new View, as your activity sees fit. > > At the outset, it may be simplest to ignore convertView and just > inflate > new Views on each getView() call. If performance suffers, you can > always > try reusing convertView. > > -- > Mark Murphy (a Commons Guy) > http://commonsware.com > _The Busy Coder's Guide to Android Development_ -- Available Now! > > > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] Announcing the new M5 SDK! http://android-developers.blogspot.com/2008/02/android-sdk-m5-rc14-now-available.html For more options, visit this group at http://groups.google.com/group/android-developers?hl=en -~----------~----~----~----~------~----~------~--~---
