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calling remove from custom adapter always removes last item

I have implemented a custom adapter and listItemView. The adapter sets an onlclick listener to a button that is on the listItemView. The onclick listener simply calls a private method I have in the adapter and passes it the position of the item to be removed. I know the position is correct because the database removes the proper item. I have found similar questions but have not been able to adapt the answers to work for me. Ideas and thoughts are greatly appreciated. Thanks.
Here is the full adapter class
public class FoodListAdapter extends ArrayAdapter<FoodListItem> {
//private
private int type;
public FoodListAdapter(Context context, ArrayList<FoodListItem> _objects) {
super(context, 0, _objects);
type = 0;
}
public FoodListAdapter(Context context, ArrayList<FoodListItem> _objects, int _type) {
super(context, 0, _objects);
type = _type;
}
#Override
public View getView(int position, View reusableView, ViewGroup parent)
{
//Cast the reusable view to a listAdpaterItemView
FoodListItemView listItemView = (FoodListItemView) reusableView;
//Check if the listAdapterItem is null
if(listItemView == null)
{
//If it is null, then create a view.
listItemView = FoodListItemView.inflate(parent, this, type);
}
if (type == 2)
{
Button deleteButton = (Button) listItemView.findViewById(R.id.listItemViewDeleteBTN);
deleteButton.setTag(new Integer(position));
}
//Now we need to set the view to display the data.
listItemView.setData(getItem(position));
return listItemView;
}
}
Here is a portion of my code used in fragment. Note that I have a private variable decalred in the class for listAdapter, though I don't think I need that.
private void displayListForDate(Calendar _date)
{
//get the list view
ListView listView = (ListView) getView().findViewById(1);
//Clear the listview by removing the listadapter and setting it to null.
//listView.setAdapter(null);
//First we must get the items.
Global global = (Global) getActivity().getApplicationContext();
DietSQLiteHelper database = global.getDatabase();
//Create a list to hold the items we ate. This list will then be added to the listView.
final ArrayList<FoodListItem> consumedList;
//Add the items to the array.
consumedList = database.getConsumed(_date.getTimeInMillis());
//Create an adapter to be used by the listView
listAdapter = new FoodListAdapter(getActivity().getBaseContext(), consumedList, 2);
//Add the adapter to the listView.
listView.setAdapter(listAdapter);
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> adapterView, View view, int position, long l) {
consumedList.remove(position);
listAdapter.notifyDataSetChanged();
}
});
}

If you didn't implement "equals" method of FoodListItem, try to implements it.

I would suggest,
that you just update the underlying data, in your case its ArrayList<FoodItems>.
In your Adapter make this simple method and change :
private List<FoodListItem> myList = new ArrayList<FoodListItem>();
public FoodListAdapter(Context context, List<FoodListItem> myList) {
super(context, 0, myList);
type = 0;
this.myList = myList;
}
public FoodListAdapter(Context context, List<FoodListItem> myList, int _type) {
super(context, 0, myList);
type = _type;
this.myList = myList;
}
// Also update your getView() method to use myList!
#Override
public View getView(int position, View reusableView, ViewGroup parent)
{
...
listItemView.setData(myList.get(position));
public void removeItem(int positio){
if(myList != null){
myList.remove(position);
}
}
And then in class, you are creating the adapter (Activity/Fragment), just call the method.
// Update the underlying ArrayAdapter
adapter.removeItem(position);
// Notify the adapter, the data has changed
adapter.notifyDataSetChanged();
Also, you shouldnt open connection to your SQLiteDatabase on UI thread, because you are blocking it. You never know, how fast is the reading from disk going to be. If it takes too long, user can think, that your application froze and therefore, he leaves, which you dont want. I would suggest to use AsyncTask, you will find a lot of examples.

I went through and cleaned up my code and it now works, here is the working code. I really don't know exactly the difference other than I updated the IDs that I was using to assign and get views. If anyone can explain the cause for the issue I was having I would appreciate it.
Here is the snippet from my fragment where I create the list view and assign an adapter.
private void displayListForDate(Calendar _date)
{
//get the list view
ListView listView = (ListView) getView().findViewById(R.id.listView);
//Clear the listview by removing the listadapter and setting it to null.
//listView.setAdapter(null);
//First we must get the items.
Global global = (Global) getActivity().getApplicationContext();
DietSQLiteHelper database = global.getDatabase();
//Create a list to hold the items we ate. This list will then be added to the listView.
ArrayList<FoodListItem> consumedList;
//Add the items to the array.
consumedList = database.getConsumed(_date.getTimeInMillis());
//Create an adapter to be used by the listView
listAdapter = new FoodListAdapter(getActivity().getBaseContext(), consumedList, 2);
//Add the adapter to the listView.
listView.setAdapter(listAdapter);
}
and here is my adapter class.
public class FoodListAdapter extends ArrayAdapter<FoodListItem>
{
//private
private int type;
public FoodListAdapter(Context context, ArrayList<FoodListItem> _objects) {
super(context, 0, _objects);
type = 0;
}
public FoodListAdapter(Context context, ArrayList<FoodListItem> _objects, int _type) {
super(context, 0, _objects);
type = _type;
}
#Override
public View getView(int position, View reusableView, ViewGroup parent)
{
//Cast the reusable view to a listAdpaterItemView
FoodListItemView listItemView = (FoodListItemView) reusableView;
//Check if the listAdapterItem is null
if(listItemView == null)
{
//If it is null, then create a view.
listItemView = FoodListItemView.inflate(parent, type);
}
if (type == 2)
{
Button deleteButton = (Button) listItemView.findViewById(R.id.listItemViewDeleteBTN);
deleteButton.setTag(new Integer(position));
deleteButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Integer tag = (Integer) view.getTag();
deleteItem(tag.intValue());
}
});
}
//Now we need to set the view to display the data.
listItemView.setData(getItem(position));
return listItemView;
}
private void deleteItem(int position)
{
FoodListItem item = getItem(position);
Global global = (Global) getContext().getApplicationContext();
DietSQLiteHelper database = global.getDatabase();
database.removeConsumed(item.getID());
remove(getItem(position));
}
}

ListVIew not updating onRestoreSaveInstanceState

Here is my method:
#Override
public void onRestoreInstanceState(Bundle savedInstanceState) {
DataBaseHandler handler = new DataBaseHandler(getApplicationContext());
//set the spinner for measurement type
Spinner measurementTypeSpinner = (Spinner) findViewById(R.id.MeasurementTypes);
ArrayAdapter adapter = (ArrayAdapter) measurementTypeSpinner.getAdapter();
int typePos = adapter.getPosition(savedInstanceState.getString("measurementtype"));
measurementTypeSpinner.setSelection(typePos);
//set the spinner for the measurement unit
Spinner measurementUnitSpinner = (Spinner) findViewById(R.id.MeasurementSubValues);
ArrayAdapter arrayAdapter = (ArrayAdapter) measurementUnitSpinner.getAdapter();
int unitPos = arrayAdapter.getPosition(savedInstanceState.getString("measurementunit"));
measurementUnitSpinner.setSelection(unitPos);
//set the value
EditText value = (EditText) findViewById(R.id.unit_value);
value.setText(savedInstanceState.getString("value"));
/**
* The list view stuff
*/
ListView unitsList = (ListView) findViewById(R.id.units_list);
unitsList.setItemsCanFocus(true);
MeasurementType mType = handler.getMeasurementType(savedInstanceState.getString("measurementtype"));
//create the converter
Converter converter = new Converter(MeasurementType.getMeasurementType(savedInstanceState.getString("measurementtype")), savedInstanceState.getString("measurementunit"), savedInstanceState.getString("value"));
//convert the values
ArrayList<Unit> convertedValues = converter.convert();
//set the adapter for the list view
unitAdapter = new UnitListAdapter(this, convertedValues, mType);
unitsList.setAdapter(unitAdapter);
}
Basically, there is another activity with a list of items and when the user checks one, it updates the database setting an int property to 1, so that when the ArrayAdapter goes through an arraylist it picks up the property as 1 and displays it, instead of 0 in which case it doesn't display it.
Now on pressing the back button, both the spinners are populated with the values I stored, the value for the EditText is restored, but the ListView is not updated, yet when I leave the app and come back in, the value that was checked is there in the list...
This says to me that I might need to do something with onStop() and onRestart() could someone please advice me. The comment saying 'the list view stuff' is where I am trying to update the list view, it just isn't working and when I debug it won't go into the restore method at all, which is confusing.
EDIT
public class UnitListAdapter extends ArrayAdapter<Unit> {
private Context context;
private ArrayList<Unit> units;
private MeasurementType type;
public UnitListAdapter(Context context, ArrayList<Unit> units, MeasurementType type) {
super(context, R.layout.unit, R.id.unit_name, units);
this.context = context;
this.units = units;
this.type = type;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View rowView = inflater.inflate(R.layout.unit, parent, false);
final TextView unitName = (TextView) rowView.findViewById(R.id.unit_name);
final EditText unitValue = (EditText) rowView.findViewById(R.id.unit_value);
if(units.get(position) != null) {
if(units.get(position).getView() == 1) {
unitName.setText(units.get(position).getUnitName());
unitValue.setText(units.get(position).getValue().toString());
} else {
unitName.setVisibility(View.GONE);
unitValue.setVisibility(View.GONE);
}
}
return rowView;
}
#Override
public void add(Unit u) {
units.add(u);
notifyDataSetChanged();
}
#Override
public void clear() {
units.clear();
notifyDataSetChanged();
}
#Override
public int getCount() {
return units.size();
}
}
As asked for. Sorry about confusion whilst editing.

onRestoreInstanceState() is not called when the user presses the back button. Most likely you need to move your logic to onResume(). I suggest that you read about the Activity lifecycle to get a better understanding about when each of the onXxx() methods are called.

After updating the list you need to call notifyDataSetChanged() to repopulate the listview.
http://developer.android.com/reference/android/widget/ArrayAdapter.html#notifyDataSetChanged()

CheckBox event listener from setChoiceMode(ListView.CHOICE_MODE_MULTIPLE)

So I have a listview that I want to add checkboxes to.
lv = (ListView)findViewById(R.id.list);
adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_multiple_choice, listItems);
lv.setAdapter(adapter);
lv.setItemsCanFocus(true);
lv.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE);
This works and the checkboxes show up. Then I have my setOnItemClickListener() for my listview because the user needs to select an item, then the next acitivty will be launched
lv.setOnItemClickListener(new AdapterView.OnItemClickListener()
{
#Override
public void onItemClick(AdapterView<?> parent, View view,int position, long id)
{
Intent components = new Intent();
components.setClass(context, ComponentsActivity.class);
components.putExtra("studyID", studyID);
components.putExtra("studyName", studyName);
startActivity(components);
}
});
However, I want to add a checkbox so that the user can tick that item in the listview to perform other actions. The problem is I can't differentiate the events. When I click on the checkbox, it gets checked but then the list item also gets selected and the new activity starts. I only want the checkbox to be affected when they click on it, not have it launch the new acitivty. I know you can also just create your own adapter but why bother if I can make a checkbox in 2 lines of code. Any suggestions? I just want to be able to check the textbox and get the id of the checked items.

I never managed to find anything for what I was looking for so I bit the bullet and decided to learn how to make my own custom adapter class. Here is my code if anybody ever runs into this problem. This adapter class is for a listview with text(TextView) and a checkbox.
public class CustomAdapter extends BaseAdapter
{
ArrayList<String> studies;
Context context;
LayoutInflater myInflater;
ArrayList<Boolean> positionArray;
public CustomAdapter(ArrayList<String> arr, Context c)
{
studies = arr;
context = c;
myInflater = (LayoutInflater)c.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
positionArray = new ArrayList<Boolean>();
for(int i = 0; i < studies.size(); ++i)
{
positionArray.add(false);
}
}
#Override
public int getCount() {
return studies.size();
}
#Override
public Object getItem(int i) {
return studies.get(i);
}
#Override
public long getItemId(int i) {
return 0;
}
public void remove(int i)
{
this.studies.remove(i);
this.positionArray.remove(i);
}
#Override
public View getView(int position, View view, ViewGroup viewGroup)
{
final int pos = position;
Holder holder = null;
//Create the views and populate it with an element from teh array
if(view == null)
view = myInflater.inflate(R.layout.custom_list_layout, viewGroup, false);//made my own layout for each listview 'cell'
holder = new Holder();
TextView study = (TextView)view.findViewById(R.id.adapterTextView);
holder.ckbox = (CheckBox)view.findViewById(R.id.adapterCheckBox);
holder.ckbox.setOnCheckedChangeListener(null);
study.setText(studies.get(position));
holder.ckbox.setFocusable(false);
//Since this method gets called whenever we scroll(view recycling), we have to re-check the checkboxes
holder.ckbox.setChecked(positionArray.get(position));
holder.ckbox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener(){
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked)
{
//checkBoxArray[pos].setChecked(isChecked);
positionArray.set(pos, isChecked);
}
});
return view;
}
static class Holder
{
CheckBox ckbox;
}
}

How to get a specific Item from a ListView by clicking on it?

First of all, I'm a beginner in android programming. So dont be too harsh :P
Anyway, I have a recycling ListView, containing an Image and a Text per List Item.
Let's say there are 100 different Items. Every Item clicked leads me to my Activity "DetailActivity.class" with the "detail_layout.xml". Now I want to configurate this layout depending on which Item was clicked.
TestActivity.java:
ArrayList<String> list = new ArrayList<String>();
for(int i = 0; i <= 99; i++) {
list.add(detail_array[i]);
//detail_array[] contains Strings which are used to add Items to the list.
}
private ListView myList = (ListView)findViewById(R.id.list);
myList.setAdapter(new MyCustomAdapter(TestActivity.this,list));
MyCustomAdapter.java:
public class MyCustomAdapter extends BaseAdapter {
private ArrayList<String> mListItemsTV;
private LayoutInflater mLayoutInflater;
public View getView(int position, View view, ViewGroup viewGroup) {
ViewHolder holder;
if (view == null) {
holder = new ViewHolder();
view = mLayoutInflater.inflate(R.layout.list_item, null);
holder.itemName = (TextView) view.findViewById(R.id.list_item_text_view);
view.setTag(holder);
} else {
holder = (ViewHolder)view.getTag();
}
String stringItem = mListItemsTV.get(position);
if (stringItem != null) {
if (holder.itemName != null) {
holder.itemName.setText(stringItem);
ImageView imageView = (ImageView) view.findViewById(R.id.list_item_image_view);
if(holder.itemName.getText() == "SomeName") {
imageView.setImageResource(R.drawable.somedrawable);
}
return view;
}
To be honest, I've got those from some kind of tutorial and I guess I know whats happening there^^
Now, how can I manage to get which Item was clicked? I tried it several times with "setOnClickListener" but it never seems to work. How do I use this? Should I use this? Where do I have to use it?

The basic idea is listview is generally dynamic so you will have a collection of an arbatrary number of items that you want to register with a listener. Oclicklistener will not work unless you register each item separate (not a good idea). Use onitemclicklistener to register the collection this link should help. http://www.ezzylearning.com/tutorial.aspx?tid=1351248&q=handling-android-listview-onitemclick-event

You'll want to use setOnItemClickListener. This is an example on how it's used. You'll need to adapt it to your code. But you can see how you would reference an individual item in the list.
listview.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, final View view,
int position, long id) {
final String item = (String) parent.getItemAtPosition(position);
view.animate().setDuration(2000).alpha(0)
.withEndAction(new Runnable() {
#Override
public void run() {
list.remove(item);
adapter.notifyDataSetChanged();
view.setAlpha(1);
}
});
}
});
}
I'll fix the formatting when I get home. On mobile ATM. If anyone wants to edit the code feel free.

If you don't want to use an adapter then try this:
#Override
public void onItemClick(AdapterView<?> parent, View view, int position,
long id) {
switch(position){
/*
* The case is the list position
*/
case 0:
break;
case 1:
break;
}
}

ListView displays item after 2nd item has been created

So I'm having a weird order of events in my code. It'll probably be something minor that I haven't seen yet. A have ListView that and is pulling the string from an EditText after button click.
The EditText lives in a dialog that's being pulled back to the main Activity by an interface
What happens now, is when I type something in the EditText field say "a", nothing shows up. But when I go to add another, "b", "a" shows up. and so forth. So one has to be created in order for the previous to show up.
Here's my what I have.
public class NewActivity extends FragmentActivity implements AddSiteDialog.AddSiteDialogListener {
ListView mSiteListView;
ArrayList<String> siteList = new ArrayList<String>();
CustomAdapter arrayAdapter = null;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.add_site);
mSiteListView = (ListView) findViewById(R.id.siteAddList);
arrayAdapter = new CustomAdapter();
mSiteListView.setAdapter(arrayAdapter);
Button b = (Button) findViewById(R.id.addSiteButton);
b.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
showDialog();
}
});
}
public void showDialog() {
FragmentManager fm = getSupportFragmentManager();
AddSiteDialog addSiteDialog = new AddSiteDialog();
addSiteDialog.show(fm, "main");
}
public void onSignIn(String inputText) {
siteList.add(inputText);
}
class CustomAdapter extends ArrayAdapter<String> {
CustomAdapter() {
super(NewActivity.this, R.layout.add_site, siteList);
}
public View getView(int position, View convertView, ViewGroup parent){
View row = convertView;
if (row == null){
LayoutInflater inflater = getLayoutInflater();
row = inflater.inflate(R.layout.list_row, parent, false);
}
((TextView) row.findViewById(R.id.textViewId)).setText(siteList.get(position));
return (row);
}
}
}
Can anyone spot where this is happening?

Simple.
call arrayAdapter.notifyDataSetChanged() in
public void onSignIn(String inputText) {
siteList.add(inputText);
//add that here
}

If the data which is backed by your adapter changes, you need to call notifyDataSetChanged() on your adapter to instruct the ListView to update itself.
I don't see anything like that in your code.
Just to add:
Your adapter implementation is sub-optimal - although in this case it doesn't really matter.
You should create a ViewHolder and store it as your View's tag, so that you can retrieve it if convertView is given. The ViewHolder should keep references to all sub-views of your view (TextView, ImageView, whatever you need to update). This would avoid the repeated call to findViewById() - which is slow.