Finally I ended up creating my own custom adapter, this way I could at least understand more easily what was happening.
I had to create actually several multiselect lists, some populated with data from the database, others from the shared preferences.
For this one displaying data from the DB, I created the following adapter (I commented out the lines about the icons because I did not set them up yet):
public class CategoriesLVAdapter extends BaseAdapter {
private Context mContext;
private LayoutInflater mInflater;
private List<Category> categoriesList;
// Constructor
public CategoriesLVAdapter(Context c, List<Category> categories_list){
mContext = c;
mInflater = LayoutInflater.from(c);
categoriesList = categories_list;
}
public List<Category> getCategoriesList(){
return categoriesList;
}
@Override
public int getCount() {
return categoriesList.size();
}
@Override
public Object getItem(int position) {
return categoriesList.get(position);
}
@Override
public long getItemId(int position) {
return categoriesList.get(position).getID();
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder = null;
if (convertView == null) {
convertView = mInflater.inflate(R.layout.categories_list_row, null);
//convertView.setLayoutParams(new ListView.LayoutParams(200, 90));
holder = new ViewHolder();
holder.title = (TextView) convertView.findViewById(R.id.categories_list_row_tv);
//holder.icon = (ImageView) convertView.findViewById(R.id.categories_list_row_iv);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
//holder.icon.setImageResource(categoriesList.get(position).getDrawableID());
//holder.icon.setAdjustViewBounds(true);
//holder.icon.setScaleType(ImageView.ScaleType.CENTER_CROP);
holder.title.setText(categoriesList.get(position).getName());
return convertView;
}
static class ViewHolder {
TextView title;
//ImageView icon;
}
}
In my activity, I use this adapter when the AlertDialog is called to populate the ListView, then I pre-select the categories using the last ones saved in the shared preferences:
private void categoriesFilter(){
AlertDialog.Builder alt_bld = new AlertDialog.Builder(this);
alt_bld.setTitle(resources.getText(R.string.select_categories).toString());
LayoutInflater inflater = (LayoutInflater) getSystemService(LAYOUT_INFLATER_SERVICE);
View layout = inflater.inflate(R.layout.categories_list,(ViewGroup) findViewById(R.id.categories_layout_root));
categoriesLV = (ListView) layout.findViewById(R.id.categories_list);
alt_bld.setPositiveButton("Ok", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int whichButton) {
String selectedCategoriesString = getSelectedValues(categoriesLV);
//Update the shared preferences
prefs.edit().putString(RateDayApplication.PREF_KEY_CATEGORIES, selectedCategoriesString).commit();
updateFilterDisplay(resources.getText(R.string.cat_title).toString(), selectedCategoriesString, searchedCategoriesTV, "Category");
}
});
alt_bld.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int whichButton) {
dialog.cancel();
}
});
String selectedCategoriesString = prefs.getString(RateDayApplication.PREF_KEY_CATEGORIES, new String());
categoriesLV.setAdapter(new CategoriesLVAdapter(this, categoriesList));
String[] selectedCategoriesArray = selectedCategoriesString.split(",");
int categoriesLVLength = categoriesLV.getCount();
for(int i = 0; i < categoriesLVLength; i++){
int categoryID = ((Category) categoriesLV.getItemAtPosition(i)).getID();
if(Arrays.asList(selectedCategoriesArray).contains(String.valueOf(categoryID))){
categoriesLV.setItemChecked(i, true);
}
}
alt_bld.setView(layout);
AlertDialog alert = alt_bld.create();
alert.show();
}
Finally here is the function I call from my database handler to get the list of catagories:
// Getting All Categories By ID desc
public List<Category> getCategoriesList() {
String selectQuery = "SELECT " + CATEGORY_ID + ", " + CATEGORY_NAME + " FROM " + CATEGORY_TABLE + " ORDER BY " + CATEGORY_ID + " ASC";
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
List<Category> categoriesList = new ArrayList<Category>();//String[] categoriesList = {};
// looping through all rows and adding to list
if (cursor.moveToFirst()) {
do {
Category category = new Category(cursor.getInt(0), cursor.getString(1), false);
categoriesList.add(category);
} while (cursor.moveToNext());
}
cursor.close();
db.close();
return categoriesList;
}
I think my problem before was coming from the fact that the function "setItemChecked" is a little misleading because it does not mean necessarily that anything is checked. When you use the function "setItemChecked", the item in the list view becomes selected, with or without a checkbox (my rows only contain text views).
The rows selected in my list appear in a different color, and that's enough in my opinion for a simple multi selection list.
The layouts I used are quite simple, "categories_list" contains a ListView in a LinearLayout and "categories_list_row" contains a TextView in a LinearLayout.
Hope it may guide someone!