Develop Reference

How to add an icon to a listview in a fragment

I made a listview in a fragment. Now I need to add a simple icon to the listview items. The icon must be the same on every item. This will be a simple arrow (imageview).
Is this possible with the listview I made? And if yes, how do I do it?
So like this format:
My text here --space--space-- >
The code for the fragment:
public class BiblioFragment extends Fragment {
final String[] items = new String[] { "Astma en alcohol", "Astma en huisdieren", "Astma en lichaamsgewicht",
"Astma en ouder worden", "Astmamedicatie", "Bekende mensen met astma", "Longfunctieonderzoek", "Reizen en vakantie",
"Sociaal leven", "Weetjes over astma", "Enzovoort", "Enzovoort", "Enzovoort" };
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_biblio, container, false);
ListView list = (ListView)view.findViewById(R.id.listView1);
ArrayAdapter<String> adapter = new ArrayAdapter<String>(getActivity(), android.R.layout.simple_list_item_1, items);
list.setAdapter(adapter);
list.setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
long arg3) {
// TODO Auto-generated method stub
Log.v("TAG", "CLICKED row number: " + arg2);
Intent myIntent = new Intent(getActivity(), BiblioDetail.class);
myIntent.putExtra("welkerij", arg2);
startActivity(myIntent);
}
});
return view;
}
}
My XML for that fragment:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:background="#ffffff">
<ListView
android:id="#+id/listView1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true" >
</ListView>
</LinearLayout>

In onCreateView
ListView list = (ListView)view.findViewById(R.id.listView1);
CustomAdapter cus = new CustomAdapter(getActivity(),items);
list.setAdapter(cus);
Use a custom adapter
public class CustomAdapter extends BaseAdapter {
String items[];
LayoutInflater mInflater;
public CustomAdapter(Context context, String[] items) {
mInflater = LayoutInflater.from(context);
this.items = items;
}
#Override
public int getCount() {
return items.length;
}
#Override
public Object getItem(int position) {
return position;
}
#Override
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.list_item,parent,false);
holder = new ViewHolder();
holder.tv = (TextView) convertView.findViewById(R.id.textView1);
holder.iv = (ImageView) convertView.findViewById(R.id.imageView1);
convertView.setTag(holder);
}
else
{
holder = (ViewHolder) convertView.getTag();
}
holder.tv.setText(items[position])
// use holder.iv to set whatever image you want according to the position
return convertView;
}
static class ViewHolder
{
ImageView iv;
TextView tv;
}
}
list_item.xml
<?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" >
<ImageView
android:id="#+id/imageView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:layout_marginLeft="42dp"
android:layout_marginTop="32dp"
android:src="#drawable/ic_launcher" />
<TextView
android:id="#+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignTop="#+id/imageView1"
android:layout_marginLeft="64dp"
android:layout_marginTop="14dp"
android:layout_toRightOf="#+id/imageView1"
android:text="TextView" />
</RelativeLayout>
Snap
Edit:
If you feel this is over kill you can use a compound textview with image on the left and text on the right.
In the above I have used list_item.xml which is a custom layout. I inflate that layout in getView of custom adapter. I set the text to textview. I have set the default launcher icon to imageview. You can change it though.
I have also used a ViewHolder
http://developer.android.com/training/improving-layouts/smooth-scrolling.html
Also check
How ListView's recycling mechanism works

Create ListAdapter
public class ListAdapter extends ArrayAdapter<Item> {
public ListAdapter(Context context, int textViewResourceId) {
super(context, textViewResourceId);
// TODO Auto-generated constructor stub
}
private List<Item> items;
public ListAdapter(Context context, int resource, List<Item> items) {
super(context, resource, items);
this.items = items;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
View v = convertView;
if (v == null) {
LayoutInflater vi;
vi = LayoutInflater.from(getContext());
v = vi.inflate(R.layout.itemlistrow, null);
}
Item p = items.get(position);
if (p != null) {
ImageView ICon = ( ImageView) v.findViewById(R.id.description);
}
}
return v;
}
In your Activity
ListView yourListView = (ListView) findViewById(R.id.itemListView);
// get data from the table by the ListAdapter
ListAdapter customAdapter = new ListAdapter(this, R.layout.itemlistrow, List<yourItem>);
yourListView .setAdapter(customAdapter);

Can't find TextView in recursive custom Listview adapter

I created this class called GeoArea, which is suppose to store "Geographical Area" that have children Geographical Areas, this is fairly strait foward:
public class GeoArea {
public String id;
public String name;
public List<GeoArea> subGeoAreas;
public GeoArea parentGeoArea;
public GeoArea(String id) {
this.id = id;
name = id;
subGeoAreas = new LinkedList<GeoArea>();
}
#Override
public String toString() {
return name;
}
}
I have created the following Layout to render it on Android, the idea here is to for each GeoArea to recursively render it self and then it's children GeoArea in a listView:
//layout_geo_area.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<TextView
android:id="#+id/txtGeoAreaName"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:gravity="left"
android:text="Geo Area Name"
android:textAppearance="?android:attr/textAppearanceLarge" />
<ListView
android:id="#+id/listViewChildGeoAreas"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_below="#+id/txtGeoAreaName"
android:gravity="left" >
</ListView>
</RelativeLayout>
This is my adapter I created for GeoArea to be displayed in a listView:
public class AdapterGeoArea extends ArrayAdapter<GeoArea>{
private ArrayList<GeoArea> _myGeoArea;
private Context _myContext;
LayoutInflater _inflater;
public AdapterGeoArea(Context context, ArrayList<GeoArea> myGeoArea) {
super(context, 0, myGeoArea);
_myGeoArea = myGeoArea;
_inflater = LayoutInflater.from(context);
_myContext = context;
}
public int getCount() {
return _myGeoArea.size();
}
public View getView(int position, View convertView, ViewGroup parent) {
GeoAreaLayoutHolder holder;
if (convertView == null) {
convertView = _inflater.inflate(R.layout.layout_geo_area,parent,false);
holder = new GeoAreaLayoutHolder();
holder.txtGeoAreaName = (TextView)convertView.findViewById(R.id.txtGeoAreaName);
holder.txtGeoAreaName.setTag(convertView);
holder.listViewChildGeoAreas = (ListView)convertView.findViewById(R.id.listViewChildGeoAreas);
holder.listViewChildGeoAreas.setTag(convertView);
} else {
holder = (GeoAreaLayoutHolder) convertView.getTag();
}
GeoArea curGeoArea = _myGeoArea.get(position);
holder.txtGeoAreaName.setText(curGeoArea.name);
if(curGeoArea.subGeoAreas.size()>0){
ArrayList<GeoArea> testList = new ArrayList<GeoArea>();
AdapterGeoArea adapter = new AdapterGeoArea(_myContext, testList);
for(GeoArea childGeoArea:curGeoArea.subGeoAreas){
testList.add(childGeoArea);
}
holder.listViewChildGeoAreas.setAdapter(adapter);
}
return convertView;
}
static class GeoAreaLayoutHolder {
public TextView txtGeoAreaName;
public ListView listViewChildGeoAreas;
}
}
And here is my Activity that I am using to set it all up:
public class ActivityGeoAreas extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.layout_geo_area);
GeoArea.searchTerm = "Bar & Grill";
GeoArea torontoArea = new GeoArea("cityOfToronto");
ArrayList<GeoArea> testList = new ArrayList<GeoArea>();
testList.add(torontoArea);
AdapterGeoArea adapter = new AdapterGeoArea(this, testList);
ListView lv = (ListView) findViewById(R.id.listViewChildGeoAreas);
lv.setAdapter(adapter);
}
}
When I try to run it, I get the error nullPointerException on the line:
holder.txtGeoAreaName.setText(curGeoArea.name);
What am I doing wrong?

You may want to check ExpandableListView may suit your needs better
http://developer.android.com/reference/android/widget/ExpandableListView.html
An example # http://www.androidhive.info/2013/07/android-expandable-list-view-tutorial/
Continuing from my previous answer to your question ( i though that solved your problem)
To display just name in your listview
list_row.xml // this is the layout with textview to be inflated in getView.
Each row will have textview
<?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" >
<TextView
android:id="#+id/textGeoArea"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_marginTop="14dp"
android:text="Choose Area"
android:textAppearance="?android:attr/textAppearanceLarge" />
</RelativeLayout>
layout_geo_area.xml // with only listview no textview
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<ListView
android:id="#+id/listViewChildGeoAreas"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:gravity="left" >
</ListView>
</RelativeLayout>
Now your adapter class
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder;
if (convertView == null) {
convertView = inflater.inflate(R.layout.list_row,parent,false);
// inflate list_row.xml with textview
holder = new ViewHolder();
holder.tv = (TextView)convertView.findViewById(R.id.textGeoArea);
holder.setTag(convertView);
}
else {
holder = (ViewHolder) convertView.getTag();
}
GeoArea curGeoArea = _myGeoArea.get(position);
holder.tv.setText(curGeoArea.name);
return convertView;
}
static class ViewHolder // use a view holder for smooth scrolling an performance
{
TextView tv;
}
You have a custom adapter.
public class AdapterGeoArea extends ArrayAdapter<GeoArea>{
Now you set the adapter to listview like below
AdapterGeoArea adapter = new AdapterGeoArea(this, testList);
ListView lv = (ListView) findViewById(R.id.listViewChildGeoAreas);
lv.setAdapter(adapter);
So why do you need the below. remove these
if(curGeoArea.subGeoAreas.size()>0){
ArrayList<GeoArea> testList = new ArrayList<GeoArea>();
AdapterGeoArea adapter = new AdapterGeoArea(_myContext, testList);
for(GeoArea childGeoArea:curGeoArea.subGeoAreas){
testList.add(childGeoArea);
}
holder.listViewChildGeoAreas.setAdapter(adapter);

Populate list in ListFragment through custom ArrayAdapter - my data doesn't show but are present in the adapter

I am new in android app dev and I am trying to create a ListFragment consisting of a TextView and a ListView. I want to try and populate the ListView with data from a custom class and thus created a custom ArrayAdapter. My app runs but doesn't show anything in the list and I can't figure out why not. I have logged the data and it is present in the holder and the text seems to be set but something is wrong.
row_layout.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="?android:attr/listPreferredItemHeight"
android:padding="6dip" >
<LinearLayout
android:orientation="vertical"
android:layout_width="0dip"
android:layout_weight="1"
android:layout_height="fill_parent">
<TextView
android:id="#+id/TextViewStation"
android:layout_width="fill_parent"
android:layout_height="0dip"
android:layout_weight="1"
android:gravity="center_vertical"
android:text="My Application" />
<TextView
android:id="#+id/TextViewType"
android:layout_width="fill_parent"
android:layout_height="0dip"
android:layout_weight="1"
android:singleLine="true"
android:ellipsize="marquee"
android:text="Simple application that shows how to use RelativeLayout" />
</LinearLayout>
</RelativeLayout>
list_layout.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<TextView
android:id="#+id/android:empty"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:text="No items to display." />
<ListView
android:id="#+id/android:list"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</LinearLayout>
SimpleArrayAdapter.java
public class SimpleArrayAdapter extends ArrayAdapter<Warning> {
private final Context context;
private final List<Warning> objects;
public SimpleArrayAdapter(Context context, int resource,
List<Warning> objects) {
super(context, resource);
this.context = context;
this.objects = objects;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
View row = convertView;
ViewHolder holder = new ViewHolder();
if (row == null) {
LayoutInflater inflater = (LayoutInflater) context
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
row = inflater.inflate(R.layout.row_layout, parent, false);
holder.v1 = (TextView) row.findViewById(R.id.TextViewStation);
holder.v2 = (TextView) row.findViewById(R.id.TextViewType);
row.setTag(holder);
} else {
holder = (ViewHolder) row.getTag();
}
final Warning warning = objects.get(position);
if (warning != null) {
holder.v1.setText(warning.getStation());
holder.v2.setText(warning.getType());
// Log.d("Adapter", "holder.v1.getText(): " + holder.v1.getText());
}
return row;
}
public static class ViewHolder {
TextView v1; // view1
TextView v2; // view2
}
#Override
public int getCount() {
return objects.size();
}
#Override
public Warning getItem(int position) {
// TODO Auto-generated method stub
return objects.get(position);
}
}
List_View.java - the ListFragment
public class List_View extends ListFragment {
List<Warning> items = new ArrayList<Warning>();
Gson gson = new Gson();
private SimpleArrayAdapter adapter;
private ListView mListView;
// #Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// ---- Get data!
JsonElement je = new JsonParser().parse(result);
JsonObject jo = je.getAsJsonObject();
JsonArray ja = jo.getAsJsonArray("warnings");
for (int i = 0; i < ja.size(); i++) {
Warning war = new Warning();
war = gson.fromJson(ja.get(i).getAsJsonObject(), Warning.class);
items.add(war);
}
// ----
}
// #Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater
.inflate(R.layout.list_layout, container, false);
// RESTManager manager = new RESTManager();
return rootView;
}
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
Log.d("Adapter", "items.size(): "+ items.size());
adapter = new SimpleArrayAdapter(getActivity(), R.layout.row_layout,
items);
setListAdapter(adapter);
}
}
In SimpleArrayAdapter, me logging the result from holder.v1.getText() returns correct value but still nothing is showing in the ListView in the app.

Try this :
#Override
public View getView(int position, View convertView, ViewGroup parent) {
View row = convertView;
TextView station, type ;
if (row == null) {
LayoutInflater inflater = (LayoutInflater) context
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
row = inflater.inflate(R.layout.row_layout, parent, false);
station = (TextView) row.findViewById(R.id.TextViewStation);
type = (TextView) row.findViewById(R.id.TextViewType);
}
Warning warning = objects.get(position);
if (warning != null) {
station.setText(warning.getStation());
type.setText(warning.getType());
// Log.d("Adapter", "holder.v1.getText(): " + holder.v1.getText());
}
return row;
}

I found the problem. Stupidly for some reason I had android:layout_width="0dip" for the textviews........ changed to android:layout_width="fill_parent" and boom, there is my data!

CustomListView onItemClickListener not working while using HorizontalScrollView, Infinitely called getView() method

I am using the following code.
Adapter.java class
public class Adapter extends ArrayAdapter<String> {
private java.util.List<String> List;
private Context context;
public Adapter(List<String> list, Context ctx) {
super(ctx, R.layout.row_item, list);
this.List = list;
this.context = ctx;
}
public View getView(int position, View convertView, ViewGroup parent) {
View v = convertView;
NameHolder holder = new NameHolder();
if (convertView == null) {
LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
v = inflater.inflate(R.layout.row_item, null);
TextView tv = (TextView)v.findViewById(R.id.textView1);
LinearLayout ll = (LinearLayout) v.findViewById(R.id.myLayout);
holder.topic_name = tv;
holder.myLayout = ll;
v.setTag(holder);
}
else
holder = (NameHolder) v.getTag();
String topic = List.get(position);
holder.topic_name.setText(topic);
ImageView imgUsers = new ImageView(context);
imgUsers.setImageResource(R.drawable.ic_launcher);
holder.myLayout.addView(imgUsers);
return v;
}
private static class NameHolder {
public TextView topic_name;
public LinearLayout myLayout;
}
}
MainActivity.java class :
public class MainActivity extends Activity {
ListView lv;
ArrayList<String> list;
Adapter myAdapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
lv = (ListView)findViewById(R.id.listView1);
list = new ArrayList<String>();
for(int i=0; i<10;i++){
list.add("Name"+i);
}
myAdapter = new Adapter(list, MainActivity.this);
lv.setAdapter(myAdapter);
lv.setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
long arg3) {
// TODO Auto-generated method stub
Toast.makeText(MainActivity.this,"lets see"+list.get(arg2), Toast.LENGTH_SHORT).show();
}
});
}
}
activity_main.xml :
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<ListView
android:id="#+id/listView1"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
</ListView>
</LinearLayout>
row_item.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="vertical" >
<TextView
android:id="#+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Large Text"
android:textAppearance="?android:attr/textAppearanceLarge" />
<HorizontalScrollView
android:id="#+id/horizontalScrollView1"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
<LinearLayout
android:orientation="horizontal"
android:id="#+id/myLayout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
></LinearLayout>
</HorizontalScrollView>
</LinearLayout>
Now, the expected output is a single image in every listItem, which tend to go to infinite.
And the onItemClickListener is not working as well.
Also, onItemClickListener works if we don't add HorizontalScrollView.
Writing onClickListener() in Adapter itself helps little as it works unpredictably.
Also, on adding a print statement in getView() and observing in Logcat, I find it difficult to understand the pattern in which getView() is called.
These are the problems I face. I require a working code of the things I wish to apply. Thanks in advance.

// Replace this code
public View getView(int position, View convertView, ViewGroup parent) {
NameHolder holder;
if (convertView == null) {
holder = new NameHolder();
LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = inflater.inflate(R.layout.row_item, null);
holder.topic_name = (TextView)convertView.findViewById(R.id.textView1);
holder.myLayout = (LinearLayout) convertView.findViewById(R.id.myLayout);
convertView.setTag(holder);
}
else
holder = (NameHolder) convertView.getTag();
String topic = List.get(position);
holder.topic_name.setText(topic);
ImageView imgUsers = new ImageView(context);
imgUsers.setImageResource(R.drawable.ic_launcher);
holder.myLayout.removeAllViews();
holder.myLayout.addView(imgUsers);
convertView.setTag(holder);
return convertView;
}

Looks like you are adding an ImageView every single time here
ImageView imgUsers = new ImageView(context);
imgUsers.setImageResource(R.drawable.ic_launcher);
holder.myLayout.addView(imgUsers);
Why don't you include the ImageView as part of your list item layout?

listview in listfragment doesnt work

i want to change my android app in that way, that i implements fragments. In the Mainactivity i am getting the content from a xml file, that i want to populate with the listview in a fragment. But unfortunatey it doesnt work, please can you help me? Here are the codes.
The fragments layout file:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<ListView
android:id="#id/android:list"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#00FF00"
android:drawSelectorOnTop="false" />
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="#+id/toptext"/>
</LinearLayout>
And this is the fragment file:
public class RoomFragment extends ListFragment {
public RoomFragment() {
}
private MyArrayAdapter mAdapter;
public static final String ARG_SECTION_NUMBER = "section_number";
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
((Dailyquran)getActivity()).main(); // Here I am calling the method in the parent activity to get the content from the xml file. It fills "Tweets"
Dailyquran basem = (Dailyquran)getActivity();
View v = inflater.inflate(R.layout.fragmentlayout, container, false);
final ListView lv = getListView();
mAdapter = new MyArrayAdapter(getActivity(), android.R.layout.simple_list_item_1, basem.tweets);
lv.setAdapter(mAdapter);
return v;
}
public class MyArrayAdapter extends ArrayAdapter<Tweet>
{
Context mContext;
private ArrayList<Tweet> tweets;
Tweet data;
public MyArrayAdapter(Context context, int textViewResourceId, ArrayList<Tweet> items)
{
super(context,textViewResourceId, items);
mContext = context;
this.tweets = items;
}
#Override
public View getView(int position, View convertView, ViewGroup parent)
{
View row = convertView;
if(row == null)
{
LayoutInflater inflater =((Activity)mContext).getLayoutInflater();
row = inflater.inflate(R.layout.fragmentlayout, null, false);
TextView tt = (TextView) row.findViewById(R.id.toptext);
}
else
{
TextView tt = (TextView) row.findViewById(R.id.toptext);
}
Tweet o = tweets.get(position);
TextView tt = (TextView) row.findViewById(R.id.toptext);
String survers=o.content;
tt.setText(survers);
return row;
}
}
}

You simply need to use the appropriate id in your ListView:
android:id="#android:id/list"