Develop Reference

How can I merge two SimpleCursorAdapters in Android?

I am using two SimpleCursorAdapters to display text and images in a row in my Listview. The problem is that when calling these Adapters two times they conflict with each other. In the end my Listview only shows the data of the SimpleCursorAdapter that I called last.
What I need to do is merge those two SimpleCursorAdapters although they use different sql databases.
Any ideas to solve this??
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.reminder_list);
mDbHelper = new RemindersDbAdapter(this);
mImageHelper = new ImageAdapter(this);
mDbHelper.open();
mImageHelper.open();
fillData();
fillImages();
registerForContextMenu(getListView());
}
//
// Fills the ListView with the data from the SQLite Database.
//
private void fillData() {
Cursor remindersCursor = mDbHelper.fetchAllReminders();
startManagingCursor(remindersCursor);
// Creates an array with the task title.
String[] from = new String[] {RemindersDbAdapter.KEY_TITLE, RemindersDbAdapter.KEY_BODY};
// Creates an array for the text.
int[] to = new int[] {R.id.text1, R.id.text2};
// SimpleCursorAdapter which is displayed.
SimpleCursorAdapter reminders = new SimpleCursorAdapter(this, R.layout.reminder_row, remindersCursor, from, to);
setListAdapter(reminders);
}
//
// Fills the ListView with the images from the SQLite Database.
//
private void fillImages() {
Cursor imageCursor = mImageHelper.fetchAllImages();
startManagingCursor(imageCursor);
// Creates an array with the image path.
String[] fromImage = new String[] {ImageAdapter.KEY_IMAGE};
// Creates an array for the text.
int[] toImage = new int[] {R.id.icon};
// SimpleCursorAdapter which is displayed.
SimpleCursorAdapter images = new SimpleCursorAdapter(this, R.layout.reminder_row, imageCursor, fromImage, toImage);
setListAdapter(images);
}

You can use the MergeCursor class to expose a number of individual cursors as a single cursor. As your adapters bind different columns->widgets, you may have to write your own subclass of SimpleCursorAdapter (or just CursorAdapter) so that you can do the correct type of binding depending on the row.

how about creating your own adapter (extend BaseAdapter) , which will point to the correct data each time it needs to ?
this way you can have full control over when and where to show each item.
you can even use the 2 adapters and use them for the new adapter.

What I need to do is merge those two SimpleCursorAdapters although they use different sql databases.
If the two adapters are truly different (e.g., different row layouts), use my MergeAdapter to combine your two existing adapters into one, then use the MergeAdapter with your ListView.
However, in your case, it would appear that you simply have two Cursors with different contents, in which case superfell's answer of using MergeCursor is probably a better approach.

Android ListView update with SimpleCursorAdapter

Hey i use a listview for demonstrate entries which are stored in a database. I also have a EditText element and a button which adds the content of the EditText into the Database. To bind the view to the database content i use the SimpleCursorAdapter and following populate function:
private void populate() {
cursor = dbAdapter.getAllItems();
startManagingCursor(cursor);
String[] from = new String[] { DBAdapter.KEY_TASK };
int[] to = new int[] { android.R.id.text1 };
// Now create an array adapter and set it to display using our row
cursorAdapter = new SimpleCursorAdapter(this, android.R.layout.simple_list_item_1, cursor, from, to);
list.setAdapter(cursorAdapter);
}
If i added a new entry, by clicking on the button i want to refresh the listview but this only works with the populate function and not with the common adapter function notifyDataSetChanged();. Do i have a bug or is this the right way to refresh a listview?

Have you seen this, tried the swap cursor method, or tried just simply calling setAdapter() again?
I had a similar issue where I could not get my list to update, and what I did was just create a refreshListView() method. Now you can call this initially from your onCreate(), AND anytime a user adds something to the DB. All it does is re-bind the listview to a cursor. With all the deprecating methods (requery()), and issues with notifyDataSetChanged(), I decided this was the easiest way.

Please refer this link...it works like charm
Update SimpleCursorAdapter while maintaining scroll position in ListView
for dynamic listview on scroll i added new item from database ..
I did mistake here ..
i was assigning new adapter for each time for same simplecursoradapter .
Instead of creating new adapter.
just use
adapter.changecursor(newcursorValue);
adapter.notifydatasetChanged();
lsMedicine1.setSelectionFromTop(lsMedicine1.getLastVisiblePosition()-20, 0);

You need to call swapcursor() before notifyDataSetChanged() on the adapter.

ListView toggle choice mode

I have a ListView (technically its a ListFragment, but I dont think that changes the question) which displays its results uisng a SimpleCursorAdapter.
adapter = new SimpleCursorAdapter(
getActivity(),
R.layout.item,
null,
new String[] {"Name"},
new int[] {R.id.Name}
);
setListAdapter(adapter);
(The Cursor is set/swapped in onStart).
I want to give the user the ability to toggle choice mode (which will than be used to display only the checked items). A bit like an SMS application when you put messages in "batch mode" which allows you to select multiple conversations which can the be deleted, saved etc. Do I set a new adapter or just change the existing ones properties? the ListView will need re-drawing anyway to reflect changes.

You have to do two things.
Use the ListView's setChoiceMode method to enable MULTI_SELECT on the ListView.
Create a 'Selector' to define a 'selected' or 'checked' state and set this as a style element on your R.layout.item.

Like Vikram Bodicherla answer.
setChoiceMode to enable MULTI_SELECT on the ListView.
Set in your custom item layout a background that show the selected state like:
android:background="?android:attr/activatedBackgroundIndicator"

This is a suprisingly simple answer. The problem was I was calling the method in onCreate before onCreateView had inflated the List. Stupdily this was just to test the function. Once I moved it to onStart and later into its intended location in the FragmentActivity the following worked fine:
public void toggleAdapter()
{
ListView listView = getListView();
if (listView.getChoiceMode() == ListView.CHOICE_MODE_MULTIPLE)
{
listView.setChoiceMode(ListView.CHOICE_MODE_SINGLE);
adapter = new SimpleCursorAdapter(
getActivity(),
R.layout.item,
dashboardCursor,
new String[] {"Name"},
new int[] {R.id.Name}
);
}
else
{
listView.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE);
adapter = new SimpleCursorAdapter(
getActivity(),
R.layout.dashboard_list_item_multiple_choice,
dashboardCursor,
new String[] {"Name"},
new int[] {R.id.Name}
);
}
listView.setAdapter(adapter);
}

SimpleCursorAdapter / ListAdapter with Multiple Sources

Is it possible to build a ListAdapter having elements come from different sources (not just one cursor).
// Build up a list of names
// Query table1.name
// Query table2.name
// Create a ListAdapter passing in the list of names.
Here's the example for creating a cursor from a single table:
SimpleCursorAdapter adapter = new SimpleCursorAdapter(this, android.R.layout.simple_list_item_1, cursor, new String[] { NAME }, new int[] {
android.R.id.text1 });
setListAdapter(adapter);
adapter.setFilterQueryProvider(m_filterQueryProvider);
if (rememberLastConstraint && m_filterQueryProvider.getConstraint() != null) {
adapter.getFilter().filter(m_filterQueryProvider.getConstraint());
}

One method would be to compile all the data for the ListView in a data structure outside the ListView adapter and then pass it to the ListView and called notify data set changed. This way you can get data from different type of sources into the ListView.

Yes. To merge cursors use MergeCursor

SimpleCursorAdapter - Binding to multiple item values in ListView

I have the following code to intantiate a SimpleCursorAdapter to use with a ListView. As you can see I have passed the R.layout.log_item to display the list items, and one value/control to bind to (TripDate).
SimpleCursorAdapter sca = new SimpleCursorAdapter(this, R.layout.log_item,c,new String[] {DBAdapter.KEY_LOG_TRIPDATE},new int[]{R.id.txtTripDate});
this works
I currently only have one widget in the layout xml, a TextView to hold the TripDate.
How do I pass multiple binding parameters for the additional widgets in the layout? so I can also display other info.
thanks
patrick

SimpleCursorAdapter sca = new SimpleCursorAdapter(this, R.layout.log_item,c,new String[] {DBAdapter.KEY_LOG_TRIPDATE, DBAdapter.KEY_FOO, DBAdapter.KEY_BAR},new int[]{R.id.txtTripDate, R.id.otherid1, R.id.otherid2});