Develop Reference

How to modify a ListView item in Android?

I'm starting learning Android and I want to know if there is some option in Android that let you modify each item or view (I don't know how it's named exactly, I mean each of the items from an ArrayList that you show in a ListView).
Well, I made a ListView that is going to show some books that were located in an ArrayList named "books".
I made a custom adapter that I associate to the ListView to show each item with the corresponding layout in the application. I also have a class "book" for each item that is going to be shown in the ListView.
Further, I made an Intent that I call from MainActivity with startForActivityResult(), that I process in Book class and that I return to MainActivity with all data of a book with the method setResult and got the information with onActivityResult() and the requestCode.
So I don't have any problem to add items to the ListView, just I have the problems if I want to modify some of the items (or views) that are located in the ListView (for example if I have title and author of a book, if I put some wrong information, I want have the option to change it).
I have that, in the same moment that you click on some of the items of the ListView, a new layout will be show to modify the information that it's wrong so I use the method setOnItemClickListener with onItemClick event on the custom adapter that I created before. Here it's where I call the new Intent to modify the wrong information with the method startActivityForResult().
I made the same as before to add a new item but, instead of add a new item with custom_adapter.addBook(title,author) I want to know if there is some option to made something like this: custom_adapter.modify(title,author) or custom_adapter.update(title,author), I mean, when you have modify all the items that were wrong of a book (for example an EditText that were "title") and you have all the information in the MainActivity class (because you returned it with setResult), how to put it again in the same item updating it in the custom_adapter and also in the ArrayList.
I searched it on the Internet but I didn't find anything.
I'm sorry if I have a poor English, but I expect that it can be understand.
Thank you very much!

If I am understanding your problem correctly - you could simply modify the ArrayList of type Book that is backing your ArrayAdapter.
So if you know what Book object you want to modify then you can simply make your changes to the Book object itself. As long as this Book is a reference to the same object that you originally added to the ArrayList you instantiated your ArrayAdapter with then you can then call custom_adapter.notifyDataSetChanged() to tell the adapter to redraw its childviews with the new data.

There are some good code samples on the Internet but you have to understand the code for your purposes. So...here is a start, look at Using an ArrayAdapter with ListView. The code shows the use of ArrayAdapter with getView() method. And I hope it shows how to define the listeners, which you need.
How about that for a start? Have fun...

Thank you very much for all help you gave to me. I'm very pleased with you. :)
Finally, I just send the info with a Bundle when I started the Intent, also with the position. And after, I just used this position to set the new info to my items (in my case, books).
Again, thank you very much ;)

How to create custom dynamic list in android?

I want to create a custom list in which items are added or removed dynamically (say when a button is tapped). The problem is I have very little knowledge of lists in android. I have gone through various tutorials on creating a custom list in android but none of them shows how to dynamically add contents to it
What I know so far:
1) I have to create a model class to store data.
2) I have to create an adapter class.
3) Pass the objects of the model class as an arraylist to the adapter.
3) Bind listview to the adapter
What's confusing me:
1) I know I have to create an apapter class, but what's really confusing me is what kind of adapter ? i.e. ArrayAdapter, BaseAdapter ??
2) What and How will I feed adapter? I will be fetching data from the Sql lite database and I want the results to be displayed in my custom made list.
3) How will I update my list when a new record is added to the database ? I know how to populate listview from a static array but its of no use in my project.
I need little guidance where should I start from ?

1) You can use ArrayAdapter.
2) After you create your own arraylist, you can pass it for first time, listview.setAdapter(...
3) After you refresh your data you can call this method, ((ArrayAdapter)listView.getAdapter).notifyDataSetChanged(). This will ensure your listview refresh.
The below link is a good example:
https://github.com/thecodepath/android_guides/wiki/Using-an-ArrayAdapter-with-ListView

Save ListView content

I have a Google's NavigationDrawer which adds/replaces fragments. One of fragments has a listView filled with custom BaseAdapter by network request (asyncTask, takes times). What i want is to save listView contents somewhere so if user navigates to another fragment through navigationDrawer and then or later navigates back to the fragment containing listView - i want a listView to be populated immediately with saved old content before asyncTask finished loading new content. Minimum API is 10.
What did i try.
onSaveInstanceState - serialize Parcelable ArrayList<CustomObject>. Somehow i didn't get it working. Also, that isn't solving my problem however, because onSaveInstaceState doesn't triggers on navigating through navigationDrawer.
Setting new fragment's InitialState(setInitialSavedState) then saving(saveFragmentInstanceSate)/loading it. That works for simple Views like EditTexts and TextView, but didn't get it working for the listView.
What is a best way to save listView contents? Please help me.

First get all items of list view.
CustomListViewAdapter listadapter = (CustomListViewAdapter) listview.getAdapter();
ArrayList<CustomObject> object=new ArrayList<CustomObject>();
for(int position=0;position<listadapter.getCount();position++)
object.add(videoadapter.getItem(position));
Now Use the object to store the items of the listview
Then use shared preferences to save the object.
Android ArrayList of custom objects - Save to SharedPreferences - Serializable?

The proper way to do this is to save your network query results in a database (sqlite), and use data from that db to display items in your list (CursorAdapter works best for this).
These tutorials nicely explain how to make your own Content Provider using Sqlite, and use a CursorAdapter to display your data on a list.
http://docs.xamarin.com/guides/android/user_interface/working_with_listviews_and_adapters/part_4_-_using_cursoradapters/
http://www.vogella.com/tutorials/AndroidSQLite/article.html

I found a good way.
String list_items = ""; // all your items are here, but separate it with a comma (,)
String[] list = list_items.separate(",");
And save the list_items in a shared preference. To retrieve just use getString() and use the code above

Add footer to an Expandable ListView

I have an expandable listView which already has some data(from database). When user opens my application, a "loading" header is displayed during which new data is pulled from the internet.
Now when the new data is received , I store it in a database and update my cursor. New data is displayed above old data.
I also have a footer which asks whether i have to load more data from the internet. Now , the footer is displayed below the old data. I want a view in between the new data and old data, i.e. below new data , so that when clicks on that view , new data is pulled from the internet , which is pushed below new data but above old data. (You can imagine twitter timeline example for understanding my problem.)
How do i implement this ?

I don't know if it will work exactly as you expect, but try MergeAdapter (link below) with added View. You will have one ListView and two same adapters - one for the old and for the new data. Between will be some View - in your case loading Button.
MergeAdapter adapter = new MergeAdapter();;
adapter.addAdapter(oldAdapter);
adapter.addView(loadingLayout);
adapter.addAdapter(newAdapter);
MergeAdapter enables to show (something like) two ListViews in single activity with single ScrollBar. But there is/was some problem with removing added Views. Check it out if this option is enabled.
Link to MergeAdapter: https://github.com/commonsguy/cwac-merge
Maybe this will be in some case helpful: http://pivotallabs.com/users/joe/blog/articles/1759-android-tidbits-6-22-2011-hiding-header-views

Problem with list activity

I have implmented pagination and it display 5 records per page. Now suppose I am on page 3 and click 3'rd element then 3'rd element of page-1 is selected.
I am not able to figure out problem as I always create new list object while setting data.
I used below code
temp = new ArrayList();
this.someListAdapter = new SomeListAdapter(this, R.layout.row_facet,temp);
setListAdapter(this.someListAdapter );
Below is signature of SomeListAdapter class.
public class SomeListAdapter extends ArrayAdapter<VoNeighborhood> {
}
Please help....

There really aren't enough details here about how you do pagination with your ListView.
So I might guess you're overriding onListItemClick and using the position variable it sends you, but you then don't take into account the page you're on?
Alternatively, just don't use pagination as you have an infinite canvas to scroll your list within — I don't think I've recall seeing an Android app so far that uses pagination!