Develop Reference

Why my ViewPager is so slow?

Inside the dialogFragment I have viewPager with two pages. Every page contains a custom adapter. One adapter with list of spinners, other adapter with list of EditTexts. ViewPager adds adapters fine.
public class PageFragment extends Fragment {
...
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.pagefragment_newprod, null);
LinearLayout ll=(LinearLayout) view.findViewById(R.id.tvLL);
ListView listView=new ListView(getActivity());
ll.addView(listView);
if (pageNumber==0){
dropDownAdapter=new DropDownAdapter(getActivity(), fillListAdapter);
listView.setAdapter(dropDownAdapter);
} else if (pageNumber==1){
boxAdapter = new BoxAdapter(getActivity(), filledFields);
listView.setAdapter(boxAdapter);
}
return view;
}
}
But it works to slow! Current Adapter (I mean at the curren page) create views every milisecond! Look at this:
public class BoxAdapter extends BaseAdapter{
...
#Override
public View getView(final int position, View convertView, ViewGroup parent) {
if (view == null) {
view = lInflater.inflate(R.layout.addproduct_item, parent, false);
}
Log.d(LOG_TAG, "====As I said every milisecond...======");
EditText editText = (EditText) view.findViewById(R.id.addProductEditText);
editText.setText(p.value);
return view;
}
}
Even when I focused the EditText this Log.d write messages every milisecond!
Besides that, adapter at the next page works too. I have other Log.d at the other adapter getView and it works when I used different page's adapter!
Please help me to understand what is wrong...(

The question has already been solved in the comments. The solution for the OP was apparently to remove complex fragments and their adapter. However, I also had complex fragments in a tab layout with a ViewPager, and the following solution fixed the slow paging problem:
viewPager.setOffscreenPageLimit(2);
The 2 will keep two pages away from the current page in memory. This was enough for me because I had three tabs. Be careful about keeping too many pages in memory, though. See the documentation.

Show empty view for ArrayAdapter in Android

I've got a ListView in my application that's rendered in a ListFragment's onActivityCreated()using setListAdapter(). Passed in to this setListAdapter()are my implementation of ArrayAdapter. At some times this adapter can be empty, and that's fine, but at those moments I would like to show a message in the list telling that there are no items, instead of just an empty view. However I don't really know how to achieve this, as for I have researched most people to show lists in a ListActivityand by doing that you can setEmptyView() but this doesn't seem doable when using a ListFragment. Another way of doing this was to change view in the ListFragment if the ArrayAdapter has no item's in it, then change view to another showing the message, but this seems to me a bit hacky.
Whats really the proper way of doing what I want to achieve?
Tried to setEmptyView() to my ListView but that didn't work either, see code on how views are inflated in my ListFragment:
public class MyFragment extends ListFragment {
#SuppressLint("InflateParams")
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
ListView listView = (ListView) inflater.inflate(R.layout.my_list, null);
listView.setEmptyView(inflater.inflate(R.layout.list_items_missing, null));
return listView;
}
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
MyItemArrayAdapter adapter = new MyItemArrayAdapter(getActivity());
// Populate adapter with items...
setListAdapter(adapter);
}
}
Shouldn't this result in the empty view beeing shown if no items exists in my adapter?

1) Try putting backgroundImage for ListView inside xml. If no item, show backgroundImage, if there is item, put background color.
2) You can also do what as #kgandroid suggested and here, setEmptyView() which you set custom view.
Example:
Another:

You can customize your adapter to show the layout R.layout.list_items_missing when (item == null) instead of inflating the normal custom list item layout that you implement.
Something like this:
public View getView(int position, View convertView, ViewGroup parent)
{
ViewHolder holder; //asuming you have this in your custom adapter
if (convertView == null) {
holder = new ViewHolder();
if(MyItemArrayList.get(position)!=null)
{
convertView = this.inflater.inflate(R.layout.layout_list_item,
parent, false);
else
{
convertView = this.inflater.inflate(R.layout.list_items_missing,
parent, false);
}
//the rest of the adapter logic
}

Tabs with Listview in fragments

I am beginner in android.
I was having a requirement similar to what is discussed here:
Separate Back Stack for each tab in Android using Fragments.
Now, I am using that project given here gitHub
What I want is to add listview to a fragment..Further on clicking a particular item in list another fragment is visible.
But I am facing a problem in doing it.
For eg here,I get error in using setListAdapter(adapter) function.
Plz help.
public class AppTabAFirstFragment extends BaseFragment {
private Button mGotoButton;
//private String[] characters= {"shs","sds","sdss","sdsd"};
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.app_tab_a_first_screen, container, false);
mGotoButton = (Button) view.findViewById(R.id.id_next_tab_a_button);
mGotoButton.setOnClickListener(listener);
// ArrayAdapter<String> adapter = new ArrayAdapter<String>(inflater.getContext(),R.layout.app_tab_d_first_screen, characters);
// setListAdapter(adapter);
return view;
}
In this way,it doesn't allow us to use setListAdapter() function reason being I can't extend ListActivity. I am all confused.
Kindly help.

I haven't checked your links, but as I can see from the little code you posted I think this might be the problem:
You need to lookup your listview from the xml file (if you have defined it there) and set the adapter to that object. For instance:
ListView listView = (ListView) view.findViewById(R.id.my_list_view);
listView.setAdapter(adapter);

problems refreshing android listview

I'm currently working on an Android app with two tabbed-fragments. One fragment consists of a pre-populated list in a listview. The other contains a dynamic list to be displayed in a listview.
I want to populate the listview on the second fragment from the list items from the first fragment.
The Problem
1) The ListView on fragment 2 doesn't populate unless the underlying adapter is initialized by a dummy list.
2) Changes on ListView are not instant. If I remove a list item from the list, the item still appears in the ListView on fragment 2. But if I switch between tabs, I see the desired List.
Here's the code:
Fragment 2
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstance) {
// listEntries = new ArrayList<InterimOrderEntry>(0);
listEntries = DummyListData.getOrder();
view = (ListView)inflater.inflate(R.layout.fragment2, container, false);
ListAdapter2 listAdapter2 = new ListAdapter2(orderEntries, getLayoutInflater(savedInstance), container);
view.setAdapter(listAdapter2);
return view;
}
ListAdapter1
private void addToList2(String itemName, int quantity, int itemImageId, Context context){
ListEntry listEntry = new ListEntry(itemName, quantity, itemImageId);
listEntries.clear();
listEntries.addAll(LisAdapter2.getOrderEntries());
listEntries.add(orderEntry);
new ListAdapter2().refreshListEntries(listEntries);
}
ListAdapter2
private static List<ListEntry> listEntries;
public void refreshListEntries(List<ListEntry> newListEntries){
listEntries.clear();
listEntries.addAll(newListEntries);
this.notifyDataSetChanged();
}
Would appreciate any help!

Figured it out, the answer was in the android docs, here's the link:
http://developer.android.com/training/basics/fragments/communicating.html

Android ListView in Fragment

I am trying to create a list of items which contains an image and some description for the image in each individual. After which, the list will be place in a fragment inside the application. Can anyone guide me to create it? I am not too sure how can I do it without the ListActivity.

It seems like your Fragment should subclass ListFragment (not ListActivity). onCreateView() from ListFragment will return a ListView you can then populate.
Here's more information on populating lists from the developer guide: Hello, ListView

Here's a code snippet to help you display ListView in a fragment.:
public class MessagesFragment extends ListFragment {
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_messages, container,
false);
String[] values = new String[] { "Message1", "Message2", "Message3" };
ArrayAdapter<String> adapter = new ArrayAdapter<String>(getActivity(),
android.R.layout.simple_list_item_1, values);
setListAdapter(adapter);
return rootView;
}
}
And, this is how the xml would look like:
<ListView
android:id="#android:id/list"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
</ListView>
If you do not use 'list' as ID or do not include a ListView into your layout, the application crashes once you try to display the activity or the fragment.
Reference: http://www.vogella.com/tutorials/AndroidListView/article.html#listfragments