getCheckedItemPositions() has a size of 0 - android

I am trying to get the positions of the views from my listview but the size of the SparseBooleanArray is always 0.
This is the code from my activity.
IngredientIndivAdapter adapter;
ListView lv;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_list_screen);
Intent intent = getIntent();
String prev_but = intent.getStringExtra("hi");
ArrayList<String> list1 = new ArrayList<String>();
list1.add("a");
list1.add("b");
list1.add("c");
list1.add("d");
list1.add("e");
adapter = new IngredientIndivAdapter(this,list1);
lv = (ListView)findViewById(R.id.listview1);
lv.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE);
lv.setAdapter(adapter);
}
public void remove_ingredient_button(View v){
SparseBooleanArray remove_list = lv.getCheckedItemPositions();
Log.d("poo",""+remove_list.size());
if(remove_list!=null)
for(int i = 0; i < remove_list.size(); i++){
if(remove_list.valueAt(i)){
View remove_view = (View)findViewById(remove_list.keyAt(i));
((LinearLayout)remove_view.getParent()).removeView(remove_view);
}
}
adapter.notifyDataSetChanged();
}
This is the XML for that activity
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context="com.JTA.recipeshoppinglist.ListScreen">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin">
<ListView
android:id="#+id/listview1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
></ListView>
</LinearLayout>
<Button
android:id="#+id/add_b"
style="?android:attr/buttonStyleSmall"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:background="#FFFF9900"
android:text="+"
android:onClick="add_button" />
<Button
android:id="#+id/remove_item"
style="?android:attr/buttonStyleSmall"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_alignParentBottom="true"
android:text="-"
android:onClick="remove_ingredient_button" />
This is my custom row XML
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal" >
<CheckBox
android:id="#+id/ingredient_check"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:checkable="true"
android:background="#FF0000" />
</LinearLayout>
And this is my custom array adapter.
public class IngredientIndivAdapter extends ArrayAdapter<String> {
static class ViewHolder{
CheckBox text;
}
ArrayList<String> list = new ArrayList<String>();
Context context;
ViewHolder viewHolder;
public IngredientIndivAdapter(Context context, ArrayList<String> iList){
super(context,R.layout.ingredient_row,iList);
this.list=iList;
this.context=context;
}
public View getView(int position, View convertView, ViewGroup parent){
if(convertView == null){
LayoutInflater inflater = ((Activity)context).getLayoutInflater();
convertView = inflater.inflate(R.layout.ingredient_row, parent, false);
viewHolder = new ViewHolder();
viewHolder.text = (CheckBox) convertView.findViewById(R.id.ingredient_check);
convertView.setTag(viewHolder);
}
else{
viewHolder = (ViewHolder)convertView.getTag();
}
viewHolder.text.setText(list.get(position));
return convertView;
}
public boolean hasStableIds(){
return true;
}
}

SparseBooleanArray checked = listView.getCheckedItemPositions();
for (int i = 0; i < listview.getCount(); i++){
if(checked.get(i)==true) {
// do something
}
}
I hope it will work.

Related

Android AlertDialog ListView w/ several TextViews and an EditText an the end

I'm trying to create an AlertDialog that has many TextViews (so that scrolling in necessary) and an EditText at the end for users to enter a value that is not included in the list. When AlertDialog is first presented, things look good. However, when I scroll back to the top after scrolling to the bottom problems occur.
Here is the bottom of the list initially presented. All good.
But here is what it looks like after I scroll to the top. Not so good.
This is the Adapter class that I am using:
public class MultiSelectOtherDialog extends DialogFragment {
public static final String TAG = "MultiSelectOtherDialog";
private ArrayList<Bean> mList = new ArrayList<>();
public static MultiSelectOtherDialog newInstance(String aTitle, String[] aElems) {
MultiSelectOtherDialog frag = new MultiSelectOtherDialog();
Bundle args = new Bundle();
args.putString("title", aTitle);
args.putStringArray("elems", aElems);
frag.setArguments(args);
return frag;
}
#Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
// length of this list determines how many items to present - need an extra for the EditText
// at the end for "Other"
int mListLen = (getArguments().getStringArray("elems").length) + 1;
//int mListLen = (getArguments().getStringArray("elems").length);
for (int i = 0; i < mListLen; i++) {
mList.add(new Bean());
}
AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
View view = getActivity().getLayoutInflater().inflate(R.layout.scb_listview2, null);
ListView listViewItems = (ListView)view.findViewById(R.id.lvScb);
listViewItems.setAdapter(new MultiSelectOtherAdapter());
listViewItems.setOnItemClickListener(new OnItemClickListenerListViewItem());
builder.setTitle(getArguments().getString("title")).setView(view);
AlertDialog diagFragDialog = builder.create();
return diagFragDialog;
}
public class MultiSelectOtherAdapter extends BaseAdapter {
#Override
public int getCount() {
return mList.size();
}
#Override
public Object getItem(int position) {
return mList.get(position);
}
#Override
public long getItemId(int position) {
return 0;
}
#Override
public View getView(final int position, View convertView, ViewGroup parent) {
ViewHolder holder;
if (convertView == null) {
holder = new ViewHolder();
// needed for the "Other" EditText at the end
if (position < mList.size() - 1) {
convertView = View.inflate(getActivity(), R.layout.scb_item, null);
holder.tv = (TextView) convertView.findViewById(R.id.tv);
Log.d(TAG, "1)");
}
else {
convertView = View.inflate(getActivity(), R.layout.scb_item_other, null);
holder.tv = (TextView) convertView.findViewById(R.id.et);
Log.d(TAG, "2)");
}
holder.cb = (SmoothCheckBox) convertView.findViewById(R.id.scb);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
Log.d(TAG, "3)");
}
final Bean bean = mList.get(position);
holder.cb.setOnCheckedChangeListener(new SmoothCheckBox.OnCheckedChangeListener() {
#Override
public void onCheckedChanged(SmoothCheckBox checkBox, boolean isChecked) {
bean.isChecked = isChecked;
}
});
// needed for the "Other" EditText at the end
if (position < getArguments().getStringArray("elems").length) {
String text = getArguments().getStringArray("elems")[position];
holder.tv.setText(text);
Log.d(TAG, "4)");
}
else {
convertView = View.inflate(getActivity(), R.layout.scb_item_other, null);
holder.tv = (TextView) convertView.findViewById(R.id.et);
holder.cb = (SmoothCheckBox) convertView.findViewById(R.id.scb);
convertView.setTag(holder);
Log.d(TAG, "5)");
}
holder.cb.setChecked(bean.isChecked);
Log.d(TAG, "6)");
return convertView;
}
class ViewHolder {
SmoothCheckBox cb;
TextView tv;
}
}
public class OnItemClickListenerListViewItem implements AdapterView.OnItemClickListener {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
Bean bean = (Bean) parent.getAdapter().getItem(position);
bean.isChecked = !bean.isChecked;
SmoothCheckBox checkBox = (SmoothCheckBox) view.findViewById(R.id.scb);
checkBox.setChecked(bean.isChecked, true);
}
}
class Bean implements Serializable {
boolean isChecked;
}
}
And the layouts:
AlertDialog layout:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<ListView
android:id="#+id/lvScb"
android:layout_height="match_parent"
android:layout_width="match_parent"
android:cacheColorHint="#0000"
android:divider="#android:color/transparent"
android:dividerHeight="0dp"
android:layout_above="#+id/viewLineHoriz" />
<View
android:id="#+id/viewLineHoriz"
android:layout_width="fill_parent"
android:layout_height="1dp"
android:layout_marginBottom="0dp"
android:layout_above="#+id/bottonRowScb"
android:background="?android:attr/dividerVertical" />
<LinearLayout
style="?android:attr/buttonBarStyle"
android:id="#+id/bottonRowScb"
android:gravity="center"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:measureWithLargestChild="true"
android:paddingTop="0dip"
android:orientation="horizontal" >
<Button
style="?android:attr/buttonBarButtonStyle"
android:id="#+id/buttonOKScb"
android:layout_width="0dip"
android:layout_height="wrap_content"
android:layout_weight="1"
android:gravity="center"
android:text="#string/ok_string" />
<View
android:id="#+id/viewLineVert"
android:layout_height="fill_parent"
android:layout_width="1dp"
android:layout_marginBottom="0dp"
android:background="?android:attr/dividerVertical" />
<Button
style="?android:attr/buttonBarButtonStyle"
android:id="#+id/buttonCancelScb"
android:layout_width="0dip"
android:layout_height="wrap_content"
android:layout_weight="1"
android:gravity="center"
android:text="#string/cancel_string" />
</LinearLayout>
</RelativeLayout>
TextView item:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
android:orientation="horizontal">
<TextView
android:id="#+id/tv"
android:layout_weight="100"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center_vertical"
android:textSize="15sp" />
<cn.refactor.library.SmoothCheckBox
android:id="#+id/scb"
android:layout_width="20dp"
android:layout_height="20dp"
android:layout_gravity="center_vertical|right"
android:layout_weight="1"
android:layout_margin="5dp"/>
</LinearLayout>
And EditText item:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
android:orientation="horizontal">
<EditText
android:id="#+id/et"
android:hint="#string/other_notes_string"
android:layout_weight="100"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center_vertical"
android:textSize="15sp"
android:textStyle="bold|italic"/>
<cn.refactor.library.SmoothCheckBox
android:id="#+id/scb"
android:layout_width="20dp"
android:layout_height="20dp"
android:layout_gravity="center_vertical|right"
android:layout_weight="1"
android:layout_margin="5dp"/>
</LinearLayout>
In your adapter change this:
#Override
public long getItemId(int position) {
return position;
}
And, also in your getView() method, put this code:
converView = null;
before :
if(convertView == null){
// your codes
}

Android - update ListView in onCreate does not work

I have the following code:
public class MainActivity extends Activity {
private ListView list;
private static final String path = Environment.getExternalStorageDirectory().getPath() + File.separator + "BOE";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
list = (ListView) findViewById(R.id.listView1);
String books[] = {"Mercedes", "Skoda", "Volkswagen", "Audi", "Citroen", "plik"};
BookArrayAdapter bma = new BookArrayAdapter(this, books);
bma.setNotifyOnChange(true);
list.setAdapter(bma);
if (!new File(path).exists()) {
new File(path).mkdirs();
}
for (int i=0; i<books.length; i++) {
View v = list.getAdapter().getView(i, null, null);
String name = ((TextView)v.findViewById(R.id.row_text)).getText() + "";
for (File f:new File(path).listFiles()) {
if (f.isFile()) {
Button b = (Button) v.findViewById(R.id.row_button);
if (name.equals(f.getName().substring(0, f.getName().length()-4))) {
b.setText("Open");
} else {
b.setText("Download");
}
bma.notifyDataSetInvalidated();
bma.notifyDataSetChanged();
Log.d("AC", b.getText().toString());
}
}
}
}
public class BookArrayAdapter extends ArrayAdapter<String> {
private final Context context;
private final String[] values;
public BookArrayAdapter(Context context, String[] values) {
super(context, R.layout.row, values);
this.context = context;
this.values = values;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
final View rowView = inflater.inflate(R.layout.row, parent, false);
final TextView textView = (TextView) rowView.findViewById(R.id.row_text);
textView.setText(values[position]);
rowView.findViewById(R.id.row_button).setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (((Button)v).getText().toString().equals("Open")) {
//open
} else {
//Download
}
}
});
return rowView;
}
}
}
and I have problems in for loop in onCreate. this Log shows correct Download/Open texts depenging on Files in file system. But the graphical representation of this list view does not changing. Here's my layout.xml:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="${relativePackage}.${activityClass}" >
<ListView
android:id="#+id/listView1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true" >
</ListView>
<RelativeLayout
android:id="#+id/main_linear_blackout"
android:layout_width="match_parent"
android:visibility="invisible"
android:layout_height="match_parent"
android:background="#CC000000" >
<ProgressBar
android:id="#+id/main_progress_startup"
style="?android:attr/progressBarStyleLarge"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true" />
</RelativeLayout>
</RelativeLayout>
and my row.xml:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/row"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_toLeftOf="#+id/row_button"
android:orientation="vertical" >
<TextView
android:id="#+id/row_text"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<ProgressBar
android:id="#+id/row_progress"
style="#android:style/Widget.ProgressBar.Horizontal"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:visibility="invisible" />
</LinearLayout>
<Button
android:id="#+id/row_button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_alignParentTop="true" />
<TextView
android:id="#+id/row_percentage"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBaseline="#+id/row_button"
android:layout_alignBottom="#+id/row_button"
android:layout_alignLeft="#+id/row_button"
android:layout_alignRight="#+id/row_button"
android:layout_alignTop="#+id/row_button"
android:gravity="center"
android:textAlignment="center"
android:textSize="20sp"
android:visibility="invisible" />
</RelativeLayout>
how to update it? What is wrong?
EDIT:
I moved editing single row to getView(...) overrided method on my adapter class. I don't really know why my first idea was wrong, but now it works.

Can't click on element in ListView Android

I am trying to create a custom list. My list is contained in a Fragment that correctly implements onScrollListener and populates the list using an adapter. The problem is that I cannot click on each item and I cannot figure out why. Here there is the code of my layout fragment
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#ffffff"
android:clickable="true">
<ListView
android:id="#+id/listNotification"
android:scrollbars="none"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:footerDividersEnabled="false"
android:headerDividersEnabled="false"
android:paddingStart="15dp"
android:paddingEnd="15dp"
android:clickable="true"
/>
</LinearLayout>
and here there is the code of my custom list
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#ffffff"
android:clickable="true">
<LinearLayout android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal"
>
<ImageView
android:id="#+id/imageNotification"
android:layout_width="60dp"
android:layout_height="60dp"
android:padding="5dp"
android:focusable="false"/>
<LinearLayout android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<TextView
android:id="#+id/textNotification"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Medium Text"
android:textAppearance="?android:attr/textAppearanceSmall"
android:layout_marginLeft="10dp"
android:layout_marginTop="5dp"
android:padding="2dp"
android:textColor="#33CC33"
android:focusable="false"/>
<TextView
android:id="#+id/idQuestion"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:visibility="gone"
android:focusable="false"
/>
<TextView
android:id="#+id/typeNotification"
android:layout_width="fill_parent"
android:layout_height="0dp"
android:visibility="gone"
android:focusable="false"/>
</LinearLayout>
</LinearLayout>
</LinearLayout>
here there is the code that creates my list using the adapter and setting the onclicklistener
adapter = new NotificationListAdapter(getActivity(), this.rows);
list = (ListView) firstAccessView.findViewById(R.id.listNotification);
list.setAdapter(adapter);
list.setOnScrollListener(this);
list.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
if(adapter.getItem(position).getTypeNotification()==0) {
mNotificationInteface.readQuestion(adapter.getItem(position).getQuestionId());
}
if(adapter.getItem(position).getTypeNotification()==1){
mNotificationInteface.readAnswer(adapter.getItem(position).getQuestionId());
}
}
});
and here there is the code of my adapter
public class NotificationListAdapter extends ArrayAdapter<NotificationItem> {
private View view;
private final Activity context;
private List<NotificationItem> rows;
private int count = 1;
public NotificationListAdapter(Activity context, List<NotificationItem> firstRows ) {
super(context, R.layout.list_notifications, firstRows);
this.context = context;
this.rows = firstRows;
}
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder;
if (convertView == null) {
LayoutInflater inflater = context.getLayoutInflater();
view = inflater.inflate(R.layout.list_notifications, null);
view.setPadding(0,10,0,10);
holder = new ViewHolder();
holder.textNotification = (TextView) view.findViewById(R.id.textNotification);
holder.idQuestion = (TextView) view.findViewById(R.id.idQuestion);
holder.typeNotification = (TextView) view.findViewById(R.id.typeNotification);
holder.imageNotification = (ImageView) view.findViewById(R.id.imageNotification);
view.setTag(holder);
} else {
view=convertView;
holder = (ViewHolder) convertView.getTag();
}
int typeNotification = this.rows.get(position).getTypeNotification();
holder.textNotification.setTextColor(Color.BLACK);
holder.idQuestion.setText(String.valueOf(this.rows.get(position).getQuestionId()));
holder.typeNotification.setText(String.valueOf(this.rows.get(position).getTypeNotification()));
if(typeNotification==0){
holder.textNotification.setText(R.string.askQuestion);
holder.imageNotification.setImageResource(R.mipmap.iconuseranonymous);
}
if(typeNotification==1){
//nome da recuperare da con id notifica, quindi id utente quindi dome
holder.textNotification.setText(R.string.answerQuestion);
Picasso.with(context).load("http://i.imgur.com/DvpvklR.png").transform(new CircleTransform()).fit().centerCrop().into(holder.imageNotification);
}
if(typeNotification==2){
//nome e immagine da recuperare
holder.textNotification.setText(R.string.newFriend);
Picasso.with(context).load("http://i.imgur.com/DvpvklR.png").transform(new CircleTransform()).fit().centerCrop().into(holder.imageNotification);
}
return view;
}
#Override
public NotificationItem getItem(int position){
return this.rows.get(position);
}
#Override
public int getCount() {
return count;
}
public void setCount(int count) {
this.count = count;
}
static class ViewHolder {
ImageView imageNotification;
TextView textNotification;
TextView idQuestion;
TextView typeNotification;
int position;
}
Remove android:clickable="true" from the ListView and it's parent in your XML layout, and also from the root of your list item layout.

How to create custom list with checkboxes and text

**Adapter class**
public class checklist extends ArrayAdapter<String> {
private final Activity context;
private final ArrayList<String> name;
public checklist(Activity context,ArrayList<String> name) {
super(context, R.layout.activity_custm_list, name);
this.context = context;
this.name = name;
}
#Override
public View getView(int position, View view, ViewGroup parent) {
LayoutInflater inflater = context.getLayoutInflater();
View rowView= inflater.inflate(R.layout.activity_custm_list, null, true);
TextView txtTitle = (TextView) rowView.findViewById(R.id.txt);
CheckBox checkBox = (CheckBox) rowView.findViewById(R.id.check);
txtTitle.setText(name.get(position));
return rowView;
}
}
adapter_xml
<?xml version="1.0" encoding="utf-8"?>
<TableLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<TableRow>
<CheckBox
android:id="#+id/check"
android:layout_width="50dp"
android:layout_height="50dp"/>
<TextView
android:id="#+id/txt"
android:layout_width="wrap_content"
android:layout_height="50dp" />
</TableRow>
</TableLayout>
listview_actitvty
public class Delete extends ActionBarActivity {
ListView lv ;
ArrayList<String> name = new ArrayList<>();
ArrayList<Integer> ids = new ArrayList<>();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_delete);
lv = (ListView) findViewById(R.id.list);
Intent intent = getIntent();
name = intent.getStringArrayListExtra("note name");
ids = intent.getIntegerArrayListExtra("id");
System.out.println("-------*********----------------"+name);
// checklist dapter = new checklist(Delete.this,name);
checklist adapter = new checklist(Delete.this, name);
lv.setAdapter(adapter);
}
activity_xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
android:layout_height="match_parent" android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
android:paddingBottom="#dimen/activity_vertical_margin"
tools:context="com.example.mohamedreda.note.Delete">
<ListView
android:id="#+id/list"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="38dp"
android:layout_below="#+id/textView"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true">
</ListView>
</RelativeLayout>
this output of system.out.print
05-11 05:19:03.072 5464-5464/com.example.mohamedreda.note I/System.outīš• -------*********----------------[alissaas, mes, hhhhhhhhh, meshoo, zeko, mostafaaaa, ahmed, hi, ahmedddd, kattttb, xxxxxxxxxxx, sssssssssssssss, -----------------------------------, a44444, n, no, mes2, zeko5, ahmed7]
error
*
java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.CheckBox.setTag(java.lang.Object)' on a null object reference
at com.example.mohamedreda.note.checklist.getView(checklist.java:32)*
you can : ""+name.get(position);
became : txtTitle.setText(""+name.get(position));

ListView from ArrayAdapter

I've Created a List view with ArrayAdapter and when i run it , its showing me an empty activity in the runtime and i don't know the wrong:
here is the MainActivity and the ArrayAdapter Classes
public class MainActivity extends Activity {
String [] title ;
ListView list;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
list = (ListView) findViewById(R.id.list);
title = getResources().getStringArray(R.array.titles);
list.setAdapter(new MyAdapter(MainActivity.this, title));
}
}
class MyAdapter extends ArrayAdapter{
String [] title;
Context context;
public MyAdapter(Context context, String[] title) {
super(context,R.layout.single_row,R.id.img);
this.title = title;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
TextView tv;
ImageView iv;
View row = convertView;
if(row==null)
{
LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
row = inflater.inflate(R.layout.single_row, parent, false);
}
tv = (TextView) row.findViewById(R.id.title);
tv.setText(title[position]);
iv = (ImageView) row.findViewById(R.id.img);
iv.setImageResource(R.drawable.arrow);
return row;
}
}
activity_main.xml that contain the ListView
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
android:layout_height="match_parent" android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
android:paddingBottom="#dimen/activity_vertical_margin" tools:context=".MainActivity">
<ListView
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:id="#+id/list"
android:layout_alignParentTop="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true" />
</RelativeLayout>
single_row.xml that contains the elements of the listview
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent" android:layout_height="match_parent">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/img"
android:src="#drawable/arrow"
android:layout_margin="15dp" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="New Text"
android:textSize="#dimen/abc_action_bar_stacked_max_height"
android:id="#+id/title"
android:layout_gravity="center_vertical" />
</LinearLayout>
</LinearLayout>
Change this line of code in your adapter.
LayoutInflater inflater = LayoutInflater.from(context);

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