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Values are not Populating in Listview [duplicate]

This question already has answers here:
Custom Adapter getView() method is not called
(6 answers)
Closed 7 years ago.
I am trying to develop an android application that can display values from multiple tables.
I have used a Base Adapter to display the values since i just need to display the queried values in a list. But when I try to display the values in the list view it is blank.
I am not sure what I have done wrong.
I am Using the below method to query the data from the database to display only the required values.
public Cursor getAssetInStore()
{
SQLiteDatabase db_database = getReadableDatabase();
Cursor c = db_database.rawQuery("SELECT asset_name,warrenty,AssetImage,asset_status FROM `Assets`,`AseetIssued` WHERE Assets.Assetid = AseetIssued.Assetissuedid AND asset_status =?" ,
new String [] {"In Storage"}, null);
return c;
}
The below methods are used to populate the values onto the list view.
private void populateAssetListView()
{
Cursor c = db_database.getAssetInStore();
AssetListView.setAdapter(new AssetListAdapter(this, c));
}
public class AssetListAdapter extends BaseAdapter
{
private Context mContext;
Cursor cursor;
public AssetListAdapter(Context context, Cursor c) {
super();
mContext = context;
cursor =c ;
}
#Override
public int getCount() {
return 0;
}
#Override
public Object getItem(int position) {
return null;
}
#Override
public long getItemId(int position) {
return 0;
}
#Override
public View getView(int position, View view, ViewGroup parent) {
LayoutInflater inflater = (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
//The layout is assigned to the custome created created in this case it is customeassetview the cales will be displayed as per this list
view = inflater.inflate(R.layout.assetsinstore_placeholder, null);
cursor.moveToPosition(position);
TextView Assetsstatus = (TextView) view.findViewById(R.id.Assetssatutsstore_view);
int status = cursor.getInt(cursor.getColumnIndex("asset_status"));
Assetsstatus .setText(String.valueOf(status));
TextView Assetsname = (TextView) view.findViewById(R.id.Assetstore_name_view);
String Assetname = cursor.getString(cursor.getColumnIndex("asset_name"));
Assetsname.setText(Assetname);
TextView Warrenty = (TextView) view.findViewById(R.id.Assetstore_Warrenty_view);
String CustDesignation = cursor.getString(cursor.getColumnIndex("warrenty"));
Warrenty .setText(CustDesignation);
ImageView AssetImage = (ImageView) view.findViewById(R.id.list_image);
byte[] bb = cursor.getBlob(cursor.getColumnIndex("AssetImage"));
AssetImage.setImageBitmap(BitmapConver.getPhoto(bb));
return view;
}
}

Try to use a cursor adapter in place of a base adapter. Moreover, beware that the position you're passing to the cursor may not be what you think.

Android notifyDatasetChange with SQLite cursor how to?

So I have 2 activities.
The first (ActivityOne) displays a listview with data from SQLite cursor, and a button.
On click of that button, I want to add an item to the listview, so I display the second activity (ActivityTwo), that contains a number of editTexts and a save Button, that does the saving in the Database.
But what I want is:
after saving the new item to the DB, the ActivityTwo should close and the ActivityOne should be displayed with the refreshed content from the DB
.
This seems a reasonable workflow. How do I achieve it?
Code for ActivityOne:
public class ActivityOne extends Activity {
private ArrayList<String> idclient = new ArrayList<String>();
private ArrayList<String> numeclient = new ArrayList<String>();
private ArrayList<String> tipclient = new ArrayList<String>();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
ListView mylist = (ListView) findViewById(R.id.lv_clienti);
LoadList();
Button btnex = (Button) findViewById(R.id.btnNewCli);
btnex.setOnClickListener(
new View.OnClickListener()
{
public void onClick(View aView)
{
Toast.makeText(getApplicationContext(), "Add new client... " , Toast.LENGTH_SHORT).show();
Intent toAnotherActivity = new Intent(aView.getContext(), NewClientActivity.class);
startActivity(toAnotherActivity);
}
}
);
}
public void LoadList(){
SQLiteDatabase db = new myDbHelper(getApplicationContext()).getWritableDatabase();
Cursor mCursor = db.rawQuery("select idclient,nameclient,typeclient from clienti order by numeclient" , null);
idclient.clear();
numeclient.clear();
tipclient.clear();
if (mCursor.moveToFirst()) {
do {
idclient.add(Integer.toString(mCursor.getInt(0)));
nameclient.add(mCursor.getString(1));
typeclient.add(mCursor.getString(2));
} while (mCursor.moveToNext());
}
DisplayClientiAdapter disadpt = new DisplayClientiAdapter(ClientiActivity.this,idclient,nameclient, typeclient);
ListView lv = (ListView) findViewById(R.id.lv_clienti);
lv.setAdapter(disadpt);
mCursor.close();
db.close();
}
}
And in the ActivityTwo, I have in a button click:
db.execSQL("insert into clients (idclient, nameclient,typeclient,...");
DisplayClientiAdapter da = new DisplayClientiAdapter(getApplicationContext());
da.notifyDataSetChanged();
finish();
Also the displayAdapter is something like:
public class DisplayClientiAdapter extends BaseAdapter {
private Context mContext;
private ArrayList<String> idclient;
private ArrayList<String> numeclient;
private ArrayList<String> tipclient;
public DisplayClientiAdapter(Context c){
this.mContext = c;
}
public DisplayClientiAdapter(Context c, ArrayList<String> idclient, ArrayList<String> numeclient, ArrayList<String> tipclient) {
this.mContext = c;
this.idclient = idclient;
this.numeclient = numeclient;
this.tipclient = tipclient;
}
public int getCount() {
return idclient.size();
}
public Object getItem(int position) {
return null;
}
public long getItemId(int position) {
return 0;
}
public View getView(int pos, View child, ViewGroup parent) {
Holder mHolder;
LayoutInflater layoutInflater;
if (child == null) {
layoutInflater = (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
child = layoutInflater.inflate(R.layout.clienti_item, null);
mHolder = new Holder();
mHolder.txt_idclient = (TextView) child.findViewById(R.id.tv_cl_id);
mHolder.txt_numeclient = (TextView) child.findViewById(R.id.tv_cl_nume);
mHolder.txt_tipclient = (TextView) child.findViewById(R.id.tv_cl_tip);
child.setTag(mHolder);
} else {
mHolder = (Holder) child.getTag();
}
mHolder.txt_idclient.setText(idclient.get(pos));
mHolder.txt_numeclient.setText(numeclient.get(pos));
mHolder.txt_tipclient.setText(tipclient.get(pos));
return child;
}
public class Holder {
TextView txt_idclient;
TextView txt_numeclient;
TextView txt_tipclient;
}
Of course it does not work like this. The list is not refreshed... I assume it has to do with the displayAdapter !?!?!
I cannot call the LoadList method since it is static or something like that...
Please help.
Thank you

Its not a problem with your adapter. You have to call Loadlist() in onresume method instead of oncreate method in ActivityOne. It will work then.

First of all, have a look at this two articles:
http://www.doubleencore.com/2013/05/layout-inflation-as-intended/
http://www.doubleencore.com/2013/06/context/
You shouldn't inflate your views with null in your inflate method if you have parent view available.
Also, using application context for inflating may cause strange behaviour, as it may not use correct theme you may've set in app manifest for your Activity.
On the other hand - why don't you use CursorAdapter instead of BaseAdapter?
The problem with your adapter is, that you don't set the data in it! :)
///EDIT:
I checked the wrong activity - why do you create second adapter in there?
The easiest solution would be to move the LoadList() to onStart.
If you want to do it right, you should use ContentObserver and (probably) CursorAdapter.

custom adapter do not refresh the listview for onclicklistener in android

I delete database entry using onclicklistener but it is not refreshing the listview. how can i refresh this listview?
This is main class for listview:
public class AFragment extends Fragment implements OnItemClickListener {
protected static final String file_name ="user";
ListView list;
Database entry;
View v;
String values[];
MySimpleArrayAdapter adapter;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
// Inflate the layout for this fragment
SharedPreferences settings = getActivity().getSharedPreferences(file_name, 0);
String name = settings.getString("name", null);
entry = new Database(getActivity());
entry.open();
values=entry.planlist(name);
entry.close();
if(values.length>0){
v = inflater.inflate(R.layout.activity_afragment, container,false);
adapter = new MySimpleArrayAdapter(getActivity(), values);
list=(ListView)v.findViewById(R.id.list);
list.setAdapter(adapter);
adapter.notifyDataSetChanged();
list.setOnItemClickListener(this);
}else{
v = inflater.inflate(R.layout.activity_my_tabs_listener, container,false);
}
// Toast.makeText(getActivity(),String.valueOf(values.length), Toast.LENGTH_LONG).show();
return v;
}
#Override
public void onItemClick(AdapterView<?> arg0, View arg1, int arg2, long arg3) {
// TODO Auto-generated method stub
Intent i = new Intent(getActivity(),Details.class);
i.putExtra("sub", values[arg2]);
startActivity(i);
Toast.makeText(getActivity(), "clicked", Toast.LENGTH_SHORT).show();
}
}
Here i use onclicklistener to delete data from database but it is not refreshing:
public class MySimpleArrayAdapter extends ArrayAdapter<String> {
private final Context context;
private final String[] values;
public Business aFragment = new Business();
int mypos =0;
ViewHolder holder;
View row;
public MySimpleArrayAdapter(Context context, String[] values) {
super(context,R.layout.activity_my_simple_array_adapter, values);
this.context = context;
this.values = values;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
mypos = position;
row = convertView;
holder = new ViewHolder();
if (row == null) {
LayoutInflater inflater = ((Activity) context).getLayoutInflater();
row = inflater.inflate(R.layout.activity_my_simple_array_adapter, parent, false);
TextView textView = (TextView) row.findViewById(R.id.text);
Button btn = (Button) row.findViewById(R.id.button1);
holder.tv = textView;
holder.btn = btn;
row.setTag(holder);
}else{
holder = (ViewHolder)row.getTag();
}
holder.tv.setText(values[position]);
final int id = position;
holder.btn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
Database entry = new Database(context);
entry.open();
entry.delete(values[id]);
entry.close();
// Toast.makeText(getContext(), String.valueOf(id), Toast.LENGTH_LONG).show();
}
});
return row;
}
static class ViewHolder{
TextView tv;
Button btn;
}
}

as anil said, you should put notifyDataSetChanged(); inside the onClickListener
this basically tells the adapter to render the list again and will call getView() again for every visible item in the list, if your code crashes, you should check two things:
first - debug the program and check that the new data fits what you want, in your case, check that the entry was deleted properly.
second - debug the getView method, step through each call and see what gives you the crash.
in your case the problem is that you are only updating the database, but in fact your listview data is taken from the values[] array which is not updated after you delete the database entry, you should create a function for updating it.

Put adapter.notifyDataSetChanged(); on click of ListView
#Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
Database entry = new Database(context);
entry.open();
entry.delete(values[id]);
entry.close();
adapter.notifyDataSetChanged();
// Toast.makeText(getContext(), String.valueOf(id), Toast.LENGTH_LONG).show();
}

If you do lots of adding and deleting to the list I think you should do the things below.
You should use ArrayList<String> instead of simple String[] so that you can easily delete. Database deletion do not effect the list directly unless you use Loaders
After you delete and item from the list, you should call notifyDataSetChanged() to the adapter. If you do not call this method, the list wont be updated.
adapter.notifyDataSetChanged();

you are removing it from the database but you are not removing it from the dataset that fills up your ListView. The simplest thing you can do is to change values from array to ArrayList, and since you are using an ArrayAdapter, you can call remove(int position). You need a List<T> of objects otherwise remove will throws an exception.

You can do one thing.
Firstly create a method called myAdapter().
In this put your creation of adapter code,so you can create new adapter for loading new data by simply calling myAdapter() method.
Whenever there should be modification in your ListView just called the following code,
listview.invalidate();
Then simply call the myAdapter().
That's it.Hope this is useful to you..:)

Custom Adapter List View

I need some help with my project. I've created a Custom Adapter, since I want my List View to display 5 textview, instead of one that I managed to do so far. This is my CustomAdapterPn activity:
public class CustomAdapterPn extends BaseAdapter {
private static ArrayList<Poniedzialek> searchPnArrayList;
private LayoutInflater mInflater;
public CustomAdapterPn(final Context context, final ArrayList<Poniedzialek> results) {
searchPnArrayList = results;
mInflater = LayoutInflater.from(context);
}
public int getCount() {
return searchPnArrayList.size();
}
public Object getItem(int position) {
return searchPnArrayList.get(position);
}
public long getItemId(int position) {
return position;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder;
if (convertView == null) {
convertView = mInflater.inflate(R.layout.entry, null);
holder = new ViewHolder();
holder.txtSession = (TextView) convertView.findViewById(R.id.textSession);
holder.txtName = (TextView) convertView.findViewById(R.id.textName);
holder.txtStart = (TextView) convertView.findViewById(R.id.textStartTime);
holder.txtEnd = (TextView) convertView.findViewById(R.id.textEndTime);
holder.txtRoom = (TextView) convertView.findViewById(R.id.textRoom);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
holder.txtSession.setText(searchPnArrayList.get(position).getTypeOfSession());
holder.txtName.setText(searchPnArrayList.get(position).getName());
holder.txtStart.setText(searchPnArrayList.get(position).getStartTime());
holder.txtEnd.setText(searchPnArrayList.get(position).getEndTime());
holder.txtRoom.setText(searchPnArrayList.get(position).getRoom());
return convertView;
}
static class ViewHolder {
TextView txtSession;
TextView txtName;
TextView txtStart;
TextView txtEnd;
TextView txtRoom;
}
}
And this is Activity where I wish to use this CustomAdapter. Note that I was using ArrayAdapter to display list items - I didn't modify the code yet, since I am clueless what should I do to manage this custom adapter correctly ( I was trying to, but nothing worked out well ). I am a newbie, so it's quite hard for me to get this, although I was reading tons of tutorials.
public class PoniedzialekActivity extends Activity implements OnClickListener, OnItemClickListener{ // z ListActivity na Activity
private Button butPnAdd;
private Button butPnDelete;
private ListView list_Pn;
private static final int DIALOG_ALERT = 10;
// We need some kind of Adapter to made the connection between ListView UI component and SQLite data set.
private ListAdapter pn_list_adapter;
// We need this while we read the query using Cursor and pass data
private ArrayList<Poniedzialek> pn_list;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.layout_poniedzialek);
butPnAdd = (Button) findViewById(R.id.butPnAdd);
butPnAdd.setOnClickListener(this);
butPnDelete = (Button) findViewById(R.id.butPnDel);
butPnDelete.setOnClickListener(this);
// Initialize UI components
list_Pn = (ListView) findViewById(R.id.listPn);
list_Pn.setOnItemClickListener(this);
pn_list = new ArrayList<Poniedzialek>();
// For the third argument, we need a List that contains Strings.
//We decided to display undergraduates names on the ListView.
//Therefore we need to create List that contains undergraduates names
pn_list_adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, populateList());
list_Pn.setAdapter(pn_list_adapter);
}
#Override
public void onClick(View v) {
if(v.getId()==R.id.butPnAdd){
Intent i = new Intent(PoniedzialekActivity.this,dodawaniePoniedzialek.class);
startActivity(i);
}
if(v.getId()==R.id.butPnDel){
showDialog(DIALOG_ALERT);
}
}
/**
* DIALOG
*/
protected Dialog onCreateDialog(int id) {
switch (id) {
case DIALOG_ALERT:
// Create out AlterDialog
Builder builder = new AlertDialog.Builder(this);
builder.setTitle("Czy na pewno chcesz usunac wszystkie wpisy ?");
builder.setCancelable(true);
builder.setPositiveButton("Tak", new OkOnClickListener());
builder.setNegativeButton("Nie", new CancelOnClickListener());
AlertDialog dialog = builder.create();
dialog.show();
}
return super.onCreateDialog(id);
}
private final class CancelOnClickListener implements
DialogInterface.OnClickListener {
public void onClick(DialogInterface dialog, int which) {
// Nic nie robi
}
}
private final class OkOnClickListener implements
DialogInterface.OnClickListener {
public void onClick(DialogInterface dialog, int which) {
DeletePn();
onResume();
}
}
public void DeletePn(){
DatabaseHelper openHelperClass = new DatabaseHelper(this);
SQLiteDatabase sqliteDatabase = openHelperClass.getWritableDatabase();
sqliteDatabase.delete(DatabaseHelper.PN_TABLE, null, null);
}
#Override
public void onItemClick(AdapterView<?> arg0, View arg1, int arg2, long arg3) {
// TODO Auto-generated method stub
}
// To create a List that contains undergraduate names, we have to read the SQLite database
//We are going to do it in the separate method
public List<String> populateList(){
// We have to return a List which contains only String values. Lets create a List first
List<String> pn_string_list = new ArrayList<String>();
// First we need to make contact with the database we have created using the DbHelper class
DatabaseHelper openHelperClass = new DatabaseHelper(this);
// Then we need to get a readable database
SQLiteDatabase sqliteDatabase = openHelperClass.getReadableDatabase();
// We need a a guy to read the database query. Cursor interface will do it for us
//(String table, String[] columns, String selection, String[] selectionArgs, String groupBy, String having, String orderBy)
Cursor cursor = sqliteDatabase.query(DatabaseHelper.PN_TABLE, null, null, null, null, null, null);
// Above given query, read all the columns and fields of the table
startManagingCursor(cursor);
// Cursor object read all the fields. So we make sure to check it will not miss any by looping through a while loop
while (cursor.moveToNext()) {
// In one loop, cursor read one undergraduate all details
// Assume, we also need to see all the details of each and every undergraduate
// What we have to do is in each loop, read all the values, pass them to the POJO class
//and create a ArrayList of undergraduates
String session = cursor.getString(cursor.getColumnIndex(DatabaseHelper.PN_KEY_TYPE_OF_SESSION));
String start = cursor.getString(cursor.getColumnIndex(DatabaseHelper.PN_KEY_START_TIME));
String end = cursor.getString(cursor.getColumnIndex(DatabaseHelper.PN_KEY_END_TIME));
String name = cursor.getString(cursor.getColumnIndex(DatabaseHelper.PN_KEY_NAME));
String room = cursor.getString(cursor.getColumnIndex(DatabaseHelper.PN_KEY_ROOM));
// Finish reading one raw, now we have to pass them to the POJO
Poniedzialek pn = new Poniedzialek();
pn.setTypeOfSession(session);
pn.setName(name);
pn.setStartTime(start);
pn.setEndTime(end);
pn.setRoom(room);
// Przekazujemy pn do arraylist
pn_list.add(pn);
// But we need a List of String to display in the ListView also.
// That is why we create "pn_string_list"
pn_string_list.add(name);
}
// Jezeli Baza Danych nie zostanie zamknieta dostaniemy error
sqliteDatabase.close();
return pn_string_list;
}
// If you don't write the following code, you wont be able to see what you have just insert to the database
#SuppressWarnings("unchecked")
#Override
protected void onResume() {
super.onResume();
pn_list_adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, populateList());
list_Pn.setAdapter(pn_list_adapter);
((ArrayAdapter<String>) pn_list_adapter).notifyDataSetChanged(); // dodano
list_Pn.refreshDrawableState(); // dodanoe
list_Pn.invalidate(); // dodanoe
}
} // end PoniedzialekActivity

Create an object for your custom adapter class CustomAdapterPn and set this custom adapter object to list view . Not the array adapter .

Look at this lines and make changes according to it,
CustomAdapterPn pn_list_adapter; //change 1
pn_list = new ArrayList<Poniedzialek>();
populateList() // Change 2
pn_list_adapter = new CustomAdapterPn(this,pn_list); // Change 3
list_Pn.setAdapter(pn_list_adapter);
Try this and let me know what happen..

Custom Spinner Crashing

I asked a question on here about a week or so ago about a custom spinner and got led to this guide. http://app-solut.com/blog/2011/03/using-custom-layouts-for-spinner-or-listview-entries-in-android/
I followed it and I've tried adapting it to work with my code and pull the results from a database onto the spinner but it keeps crashing.
This is the code for the spinner.
public class EditTeam extends Activity {
private final List<SpinnerEntry> spinnerContent = new LinkedList<SpinnerEntry>();
private Spinner D1Spinner;
private final ETSpinnerAdapter D1Adapter = new ETSpinnerAdapter(spinnerContent, this);
DataBaseHelper myDbHelper = new DataBaseHelper(this);
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.editteam);
myDbHelper = new DataBaseHelper(this);
myDbHelper.openDataBase();
fillSpinner();
}
private void fillSpinner() {
Cursor c = myDbHelper.FetchDrivers();
startManagingCursor(c);
// create an array to specify which fields we want to display
String[] from = new String[]{"FirstName", "LastName"};
// create an array of the display item we want to bind our data to
int[] to = new int[]{android.R.id.text1};
spinnerContent.add(new SpinnerEntry(1, null, "Test"));
//adapter.setDropDownViewResource( R.layout.spinner_entry_with_icon );
D1Spinner = (Spinner) findViewById(R.id.spr_Driver1);
D1Spinner.setAdapter((SpinnerAdapter) D1Adapter);
}
}
And I am using the two classes from that contacts example which are un-modified at the moment.
As you can see I'm trying to just manually add one item at the moment but it just crashes when you load it.
This seems to be the breaking point?
05-25 15:17:34.773: E/AndroidRuntime(241): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.f1manager.android/com.f1manager.android.EditTeam}: java.lang.ClassCastException: com.f1manager.android.ETSpinnerAdapter
Any ideas would be great.
Thanks.
ETSpinnerAdapter Code (Unmodified from the original code in the example):
public class ETSpinnerAdapter {
private final List<SpinnerEntry> content;
private final Activity activity;
public ETSpinnerAdapter(List<SpinnerEntry> content, Activity activity) {
super();
this.content = content;
this.activity = activity;
}
public int getCount() {
return content.size();
}
public SpinnerEntry getItem(int position) {
return content.get(position);
}
public long getItemId(int position) {
return position;
}
public View getView(int position, View convertView, ViewGroup parent) {
final LayoutInflater inflater = activity.getLayoutInflater();
final View spinnerEntry = inflater.inflate(
R.layout.spinner_entry_with_icon, null); // initialize the layout from xml
final TextView contactName = (TextView) spinnerEntry
.findViewById(R.id.spinnerEntryContactName);
final ImageView contactImage = (ImageView) spinnerEntry
.findViewById(R.id.spinnerEntryContactPhoto);
final SpinnerEntry currentEntry = content.get(position);
contactName.setText(currentEntry.getContactName());
//contactImage.setImageBitmap(currentEntry.getContactPhoto());
return spinnerEntry;
}
}

It would seem like your ETSpinnerAdapter is not a SpinnerAdapter as your are getting a class cast exceptin. Maybe you can post your code for the ETSpinnerAdapter?