Add custom listview to a fragment - java

I am trying to work with a custom listview in a fragment, and I tried a lot of things, I watched videos and I looked for solutions in this site, but I get confused because it doesn't work.
My problem is that in the code, I can't make work the custom adapter, it crash when the fragment inflates, and with the "(AppCompatActivity)" added, it doesn't crash but the listview doesn't show anything.
Is there something I could do with this?
Should I try another thing?
This is the Fragment I want to use the ListView
public class RecordFragment extends Fragment {
private ArrayList<Record> scoreList;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_record, container, false);
scoreList= new ArrayList<>();
scoreList.add(new Record("Math", 10, "9/1/2017 13:45"));
scoreList.add(new Record("Math", 8, "7/5/2017 10:50"));
scoreList.add(new Record("Marh", 4, "7/7/2017 16:30"));
CustomAdapter adapter = new CustomAdapter(RecordFragment.this.getActivity(), android.R.layout.simple_list_item_1, scoreList);
ListView list1 = (ListView)view.findViewById(R.id.list1);
list1.setAdapter(adapter);
return view;
}
private class CustomAdapter extends ArrayAdapter<Record>{
AppCompatActivity appCompatActivity;
CustomAdapter(AppCompatActivity context){
super(context, R.layout.record_fragment, scoreList);
appCompatActivity = context;
}
public View getView(int position, View convertView, ViewGroup parent){
LayoutInflater inflater = appCompatActivity.getLayoutInflater();
View item = inflater.inflate(R.layout.record_fragment, null);
TextView tv1, tv2, tv3;
tv1 = (TextView)item.findViewById(R.id.tv1);
tv2 = (TextView)item.findViewById(R.id.tv2);
tv3 = (TextView)item.findViewById(R.id.tv3);
tv1.setText(scoreList.get(position).getTest());
tv2.setText(scoreList.get(position).getScore());
tv3.setText(scoreList.get(position).getDate());
return item;
}
}
public interface OnFragmentInteractionListener {
void onFragmentInteraction(Uri uri);
}
}
This is the XML with the visual interface of each ListView item
<TextView
android:id="#+id/tv1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="" />
<TextView
android:id="#+id/tv2"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="" />
<TextView
android:id="#+id/tv3"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="" />
And this is the class I created to represent each ListView item
class Record{
private String test, date;
private int score;
public Record(String test, int score, String date)
{
this.test= test;
this.score= score;
this.date = date;
}
public String getTest() {
return test;
}
public int getScore(){
return score;
}
public String getDate(){
return date;
}
}
If there is something else I have to show tell me, please.
Beforehand, thank you.
EDIT: I fixed some spelling mistakes. And this line in the Fragment doesn't compile:
CustomAdapter adapter = new CustomAdapter(RecordFragment.this.getActivity(), android.R.layout.simple_list_item_1, scoreList);
This message is displayed when I try to run it (I guest is the error log):
Error:(39, 40) error: constructor CustomAdapter in class RecordFragment.CustomAdapter cannot be applied to given types;
required: AppCompatActivity
found: FragmentActivity,int,ArrayList
reason: actual and formal argument lists differ in length

According to your question you are facing this problem
after adding AppcompatActivity your app is not crashing but list is not showing anything
Your Adapter is asking for Context from your Activity which is AppCompat Type . So if when your host activity is not extending AppcompatActivity it will crash
So when you change it to AppcompatActivity it won't crash
Now lets solve the problem of showing a blank listView
you didn't override the parent method getCount() . In the getCount() method return size items in your List.
Another thing CustomAdapter adapter = new CustomAdapter(RecordFragment.this.getActivity(), android.R.layout.simple_list_item_1, scoreList); I don't think your code compiles with this line as your AdaptadorHistorial(AppCompatActivity context){
super(context, R.layout.record_fragment, scoreList);
appCompatActivity = context;
} custom adapter is taking one parameter but you are passing two
your constructor should be like this
AdaptadorHistorial(Context context , List<Record> scoreList){
super(context, R.layout.record_fragment, scoreList);
this.context = context;
this.items = scoreList;
}
#override
public int getCount(){
return items.size();
}

Related

ListView from an array received as string from a RecyclerView

I have a main activity that has a Recyclerview, It displays a list image and a text as the title.
In the main activity I have three array lists; one for the image, one for its title and the last one "array" for a String array.
I am passing the R.array.id as a string into the next activity On Click of an item in the MainActivity. I send the image, title, and the array.
In the second Activity, where I check for incoming intent, Assign them to strings.
String imageUrl = getIntent().getStringExtra("image_url");
String imageName = getIntent().getStringExtra("image_name");
String array= getIntent().getStringExtra("array_id");
Then I have called setArray(array) and then inside the function, I got stuck.
private void setArray(String array) {
// Stuck here
}
I don't know what to do. I have set a ListView in the second layout
and found this code on this site.
ListView lv = (ListView) findViewById(R.id.extView);
ArrayAdapter<CharSequence> aa = ArrayAdapter.createFromResource(this, R.array.id, android.R.layout.simple_list_item_1);
lv.setAdapter(aa);
Which works, if I have a set the source to a static array id but how do I set it the string I receive?
Tried getString(array), which did not work. I also need to set an onClick listener to the items.
For displaying an array in a ListView, you need to have a custom adapter. The ArrayAdapter that you are currently using, is the native adapter for showing a list provided by Android SDK. However, you need a custom class if you need to show the ListView which populates the items dynamically from your array.
In order to do that, you need to have a custom adapter class like the following.
public class ListAdapter extends ArrayAdapter<String> {
private int resourceLayout;
private Context mContext;
public ListAdapter(Context context, int resource, List<String> items) {
super(context, resource, items);
this.resourceLayout = resource;
this.mContext = context;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
View v = convertView;
if (v == null) {
LayoutInflater vi;
vi = LayoutInflater.from(mContext);
v = vi.inflate(resourceLayout, null);
}
String p = getItem(position);
if (p != null) {
TextView tt1 = (TextView) v.findViewById(R.id.id);
tt1.setText(p.getId());
}
return v;
}
}
Now you need a layout which indicates each item of your list. For example, the name of your layout is list_item.xml.
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_height="wrap_content" android:orientation="vertical"
android:layout_width="fill_parent">
<TextView
android:id="#+id/id"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="left"
android:height="40sp" />
</LinearLayout>
Now in your second Activity, you need to initialize the adapter and set the adapter in your ListView like the following. Please note that, as the adapter takes a List, you need to convert your array string from a String to a List and then pass it to the adapter.
// I assume, the String is comma separated, which indicates the array.
List<String> arrayList = Arrays.asList(array.split("\\s*,\\s*"));
ListView lv = (ListView) findViewById(R.id.extView);
ListAdapter customAdapter = new ListAdapter(this, R.layout.list_item, arrayList);
lv.setAdapter(customAdapter);
Hope that helps!

Settings tab titles with SmartTabLayout using custom adapter and extending PagerAdapter

I have a custom adapter for my ViewPager and I was wondering if there was any way to the set title of each tab using SmartTabLayout ? I've opened an ticket with them there, but I was hoping someone would know how to do this. The following is my custom adapter:
public class CustomPagerAdapter extends PagerAdapter {
private int[] image_resources = {
R.drawable.image1,
R.drawable.image2,
R.drawable.image3,
R.drawable.image4,
R.drawable.image5,
};
private Context ctx;
private LayoutInflater layoutInflater;
public CustomPagerAdapter(Context ctx) {
this.ctx = ctx;
}
#Override
public int getCount() {
return image_resources.length;
}
#Override
public boolean isViewFromObject(View view, Object o) {
return (view == (RelativeLayout) o);
}
#Override
public Object instantiateItem(ViewGroup container, int position) {
layoutInflater = (LayoutInflater) ctx.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View item_view = layoutInflater.inflate(R.layout.pager_item, container, false);
ImageView imageview = (ImageView) item_view.findViewById(R.id.image_view);
imageview.setImageResource(image_resources[position]);
container.addView(item_view);
return item_view;
}
#Override
public void destroyItem(ViewGroup container, int position, Object object) {
container.removeView((RelativeLayout) object);
}
}
This is how I set up my ViewPager, and also where I initiate SmartTabLayout:
final ViewPager viewPager;
CustomPagerAdapter adapter;
viewPager = (ViewPager) findViewById(R.id.view_pager);
adapter = new CustomPagerAdapter(context);
viewPager.setAdapter(adapter);
SmartTabLayout viewPagerTab = (SmartTabLayout) findViewById(R.id.viewpagertab);
viewPagerTab.setViewPager(viewPager);
I suppose I should include the relevant portions of my XML as well:
<com.ogaclejapan.smarttablayout.SmartTabLayout
android:id="#+id/viewpagertab"
android:layout_width="match_parent"
android:layout_height="48dp"
android:background="#fff"
app:stl_indicatorAlwaysInCenter="false"
app:stl_indicatorWithoutPadding="false"
app:stl_indicatorInFront="false"
app:stl_indicatorInterpolation="smart"
app:stl_indicatorGravity="bottom"
app:stl_indicatorColor="#33ffcc"
app:stl_indicatorThickness="4dp"
app:stl_indicatorCornerRadius="2dp"
app:stl_overlineColor="#4D000000"
app:stl_overlineThickness="0dp"
app:stl_underlineColor="#4D000000"
app:stl_underlineThickness="1dp"
app:stl_dividerColor="#4D000000"
app:stl_dividerThickness="1dp"
app:stl_defaultTabBackground="?attr/selectableItemBackground"
app:stl_defaultTabTextAllCaps="true"
app:stl_defaultTabTextColor="#FC000000"
app:stl_defaultTabTextSize="12sp"
app:stl_defaultTabTextHorizontalPadding="16dp"
app:stl_defaultTabTextMinWidth="0dp"
app:stl_distributeEvenly="false"
app:stl_clickable="true"
app:stl_titleOffset="24dp"
app:stl_drawDecorationAfterTab="false"
/>
<android.support.v4.view.ViewPager
android:id="#+id/view_pager"
android:layout_width="match_parent"
android:layout_height="500dp"
android:clickable="false"
android:layout_below="#id/viewpagertab"
android:scaleType="centerCrop" />
It actually works fine, but I can't set the titles in the standard way using getPageTitle() so they come up blank. I would like to continue to use SmartTabLayout because of how aesthetically appealing it is. The default pager titles are horrendous!
As far as I understand the documentation, you need a FragmentPagerItemAdapter and call .add("title", class):
FragmentPagerItemAdapter adapter = new FragmentPagerItemAdapter(
getSupportFragmentManager(), FragmentPagerItems.with(this)
.add(R.string.titleA, PageFragment.class) // I assume titles are set here.
.add(R.string.titleB, PageFragment.class)
.create());
So, you simply would need to call adapter.add(...)?
Edit:
Looked into the demo app - I think you'll need to extend FragmentPagerItemAdapterinstead of simple PagerAdapter
Apparently it does work by extending PagerAdapter alone. So the correct answer in this context is to override getPageTitle() in the custom pager adapter class, CustomPagerAdapter:
#Override
public CharSequence getPageTitle(int position) {
return title_resources[position];
}
You can return a String[] array in order to provide titles to each tab. Just make sure your number of titles are equal to the number of images or views in your ViewPager:
private String[] title_resources = {
"Title 1",
"Title 2",
"Title 3",
"Title 4",
"Title 5",
};

Android: How to use extended layout class as ListView row?

I'm creating a simple chess clock -type timer app. I'm trying to show the players and the time they have left as rows in a ListView. I'm using a custom view that extends RelativeLayout for these rows, so that I can give it methods that highlight the player in turn, for example.
Row layout class:
public class GameTimerView extends RelativeLayout {
private TextView nameView;
private TextView timerView;
public GameTimerView(Context context) {
super(context);
LayoutInflater inflater = LayoutInflater.from(context);
inflater.inflate(R.layout.timer_view, this);
loadViews();
}
...
private void loadViews() {
nameView = (TextView)findViewById(R.id.nameView);
timerView = (TextView)findViewById(R.id.timerView);
}
public void setName(String name) {
nameView.setText(name);
}
public void setTime(long timeInMillis) {
timerView.setText(String.format("%02d:%02d",
TimeUnit.MILLISECONDS.toMinutes(timeInMillis),
TimeUnit.MILLISECONDS.toSeconds(timeInMillis) -
TimeUnit.MINUTES.toSeconds(TimeUnit.MILLISECONDS.toMinutes(timeInMillis))
));
}
public void setActive() {
this.nameView.setTextColor(Color.GREEN);
}
public void setInactive() {
nameView.setTextColor(Color.BLACK);
}
}
Row layout XML (timer_view.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="wrap_content" >
<TextView
android:id="#+id/nameView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_toLeftOf="#+id/timerView"
android:text="#string/player_default_name" />
<TextView
android:id="#+id/timerView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:text="#string/zero_time" />
</RelativeLayout>
Adapter:
public class playerArrayAdapter extends ArrayAdapter<Player> {
private final Context context;
private final ArrayList<Player> players;
public playerArrayAdapter(Context context, ArrayList<Player> values) {
super(context, R.layout.timer_view, values);
this.context = context;
this.players = values;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
GameTimerView playerView = new GameTimerView(context);
players.get(position).setTimerView(playerView);
return playerView;
}
}
Player class setTimerView function:
public void setTimerView(GameTimerView timer) {
this.timerView = timer;
this.timerView.setName(this.name);
this.timerView.setTime(this.totalCountDown);
this.timerView.setInactive();
}
In the activity's onCreate method:
playerArrayAdapter playersAdapter = new playerArrayAdapter(
getApplicationContext(),
game.getPlayers()
);
ListView playersView = (ListView) findViewById(R.id.playerList);
playersView.setAdapter(playersAdapter);
At first this seems to work, and the desired player names and times are rendered to the list properly. However, if I later programmatically call for example Player.timerView.setActive(), nothing happens.
Having looked at dozens of examples of custom adapters for ListViews none of them seems to be using it this way - the view is always inflated directly in Apdater.getView(). I want the flexibility of an extended view class however, but apparently I'm doing something wrong.
So, what's the correct way to use custom view class for ListView rows?
First, when inflating your GameTimerView, you've got a RelativeLayoutinside another.
Second, to answer the question : it might be good not to re-create a view on each call to ArrayAdapter.getView(), but instead modify playerArrayAdapter by adding a cache like this :
private List<View> views;
public playerArrayAdapter(Context context, ArrayList<Player> values) {
super(context, R.layout.timer_view, values);
views = new ArrayList<View>(values.length);
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
View playerView;
if (position < views.size()) {
playerView = views.get(position);
if (playerView != null)
return playerView;
} else {
while (views.size() < position)
views.add(null);
}
playerView = new GameTimerView(context);
views.add(position, playerView);
players.get(position).setTimerView(playerView);
return playerView;
}
If this successfully corrects your problem, it means that previously, when setting a player as active the ListView was getting all views again for rendering, recreating them, and doing so, erasing any previous state.
As per your getView() method of Adapter, it will create a new view always that might have causing you issue.
If you really want to implement a CustomViewGroup then please refer this good implementation of the custom view here. Hope this will help you to start.

Do I need fragments and how to access them?

I am new to Android so my question may seem ridiculous but I cant figure it out.
I started creating an app some time ago and using 'Create new Android Activity' usually created a .java and .xml file for it, and everything worked. Now, after update when I use 'Create new Android Activity' it creates .java with class (which now extends ActionBarActivity and not Activity as before) and it adds a fragment_nameofactivity.xml + all things to make it work like internal class extending Fragment...
Now I used to do some ListView display on the page and without a fragment it all works great, but when fragment got introduced I can no longer findViewById(R.id.list_view) if its inside a fragment...
My question is do I need to place my whole functionality inside the class extending Fragment? I tried but it didn't work... Or do I still write all my functionality in the original class and then somehow access the listView in the fragment...
Here is the code:
public class PlayersActivity extends ActionBarActivity {
PlayerDataDatabaseAdapter playerDataHelper;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_players);
if (savedInstanceState == null) {
getSupportFragmentManager().beginTransaction()
.add(R.id.container, new PlaceholderFragment()).commit();
}
playerDataHelper = new PlayerDataDatabaseAdapter(this);
playerDataHelper.open();
displayPlayersList();
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.players, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
/**
* A placeholder fragment containing a simple view.
*/
public static class PlaceholderFragment extends Fragment {
public PlaceholderFragment() {
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_players,
container, false);
return rootView;
}
}
private void displayPlayersList() {
Cursor cursor = playerDataHelper.getAllPlayers();
String [] columns = playerDataHelper.columnsToBind();
int [] to = new int[] {
R.id.player_name,
};
SimpleCursorAdapter dataAdapter = new SimpleCursorAdapter(this, R.layout.fragment_player_details, cursor, columns, to, 0);
ListView listView = (ListView) findViewById(R.id.players_list);
listView.setAdapter(dataAdapter);
listView.setOnItemClickListener(new OnItemClickListener(){
#Override
public void onItemClick(AdapterView<?> listView, View view, int position, long id) {
Cursor cursor = (Cursor) listView.getItemAtPosition(position);
int player_id = cursor.getInt(cursor.getColumnIndexOrThrow("_id"));
Intent intent = new Intent(PlayersActivity.this, EditPlayerActivity.class);
intent.putExtra("PlayerId", player_id);
startActivity(intent);
}
});
}
public void addNewPlayer(View view) {
Intent intent = new Intent(this, AddPlayerActivity.class);
startActivity(intent);
}
}
Fragment_players.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: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="uk.co.eximage.soccermum.PlayersActivity$PlaceholderFragment" >
<TextView
android:id="#+id/textView1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_alignParentTop="true"
android:text="#string/players"
android:textAppearance="?android:attr/textAppearanceLarge" />
<Button
android:id="#+id/button1"
style="?android:attr/buttonStyleSmall"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal = "true"
android:layout_below="#+id/textView1"
android:onClick="addNewPlayer"
android:text="#string/add_player" />
<ListView
android:id="#+id/players_list"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="#+id/button1"
>
</ListView>
</RelativeLayout>
activity_players.xml:
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/container"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="uk.co.eximage.soccermum.PlayersActivity"
tools:ignore="MergeRootFrame" />
Running this returns NullPointerException on the line that tries to get players_list:
ListView listView = (ListView) findViewById(R.id.players_list);
after this listView is null.
What am I doing wrong?
And finally do I need fragments? Maybe I should just remove them and do it the 'old' way with one view per page?
You need to iniaitlize ListView in Fragment
ListView listView;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_players,
container, false);
listView = (ListView)rootView. findViewById(R.id.players_list);
playerDataHelper = new PlayerDataDatabaseAdapter(getActivity());
playerDataHelper.open();
displayPlayersList();
The ListView belongs to fragment_players.xml. Move all your code related to fragment in onCreateView.
Edit:
public static class PlaceholderFragment extends Fragment {
public PlaceholderFragment() {
}
ListView listView;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_players,
container, false);
listView = (ListView)rootView. findViewById(R.id.players_list);
playerDataHelper = new PlayerDataDatabaseAdapter(getActivity());
playerDataHelper.open();
displayPlayersList();
return rootView;
}
private void displayPlayersList() {
Cursor cursor = playerDataHelper.getAllPlayers();
String [] columns = playerDataHelper.columnsToBind();
int [] to = new int[] {
R.id.player_name,
};
SimpleCursorAdapter dataAdapter = new SimpleCursorAdapter(getActivity(), R.layout.fragment_player_details, cursor, columns, to, 0);
listView.setAdapter(dataAdapter);
listView.setOnItemClickListener(new OnItemClickListener(){
#Override
public void onItemClick(AdapterView<?> listView, View view, int position, long id) {
Cursor cursor = (Cursor) listView.getItemAtPosition(position);
int player_id = cursor.getInt(cursor.getColumnIndexOrThrow("_id"));
Intent intent = new Intent(getActivity(), EditPlayerActivity.class);
intent.putExtra("PlayerId", player_id);
startActivity(intent);
}
});
}
}
Fragments were introduced to better support the tablet form factor. If you don't plan to rearrange your display (ie. show list and detail view together), you don't need fragments and can go the old way.
You should have to initialize Listview from fragment rootView
Either you have to Declare ListView globally and intialize inside onCreateView of Fragment or have to declare View rootView globally and initialize listview by
ListView listView = (ListView) rootView .findViewById(R.id.players_list);

ListView row buttons: How do I create a custom Adapter that connects a View.OnClickListener to a button on each row of a ListView?

I want my ListView to contain buttons, but setting the button's xml property, onClick="myFunction" and then placing a public void myFunction(android.view.View view) method in the activity causes an NoSuchMethodException (the stack trace is null) to be thrown, as although the onclick listener is there, it doesn't fire myFunction(...) and cause the activity to close.
How do I create a custom Adapter that connects a View.OnClickListener to a button on each row of a ListView?
My ListView is created as follows...
[activity.java content..]
public void myFunction(android.view.View view)
{
//Do stuff
}
[activity.xml content..]
<LinearLayout xmlns:tools="http://schemas.android.com/tools" xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" tools:context=".FrmCustomerDetails" >
<ListView android:id="#+id/LstCustomerDetailsList" android:layout_width="fill_parent" android:layout_height="0dip" android:layout_weight="1" android:clickable="true" android:clipChildren="true" android:divider="#null" android:dividerHeight="0dp" android:fastScrollEnabled="true" android:footerDividersEnabled="false" android:headerDividersEnabled="false" android:requiresFadingEdge="vertical" android:smoothScrollbar="true" />
</LinearLayout>
[activity_row_item.xml content..]
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:id="#+id/Llt" android:layout_width="match_parent" android:layout_height="match_parent" >
<Button android:id="#+id/Btn" android:text="Click me" android:onClick="myFunction" />
</LinearLayout>
Here is how to create the custom Adapter, connecting View.OnClickListener to a ListView with a button per row...
1. Create a layout for a typical row
In this case, the row is composed of three view components:
name (EditText)
value (EditText:inputType="numberDecimal")
delete (Button)
Xml
pay_list_item.xml layout is as follows:
<?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" >
<EditText
android:id="#+id/pay_name"
android:layout_width="0dp"
android:layout_height="fill_parent"
android:layout_weight="2"
android:hint="Name" />
<EditText
android:id="#+id/pay_value"
android:layout_width="0dp"
android:layout_height="fill_parent"
android:layout_weight="1"
android:inputType="numberDecimal"
android:text="0.0" />
<Button
android:id="#+id/pay_removePay"
android:layout_width="100dp"
android:layout_height="fill_parent"
android:text="Remove Pay"
android:onClick="removePayOnClickHandler" />
</LinearLayout>
Note: the button has onClick handler defined in xml layout file, because we want to refer its action to a specific list item.
Doing this means that the handler will be implemented in Activity file and each button will know which list item it belongs to.
2. Create list item adapter
This is the java class that is the controller for pay_list_item.xml.
It keeps references for all of its views, and it also puts these references in tags, extending the ArrayAdapter interface.
The Adapter:
public class PayListAdapter extends ArrayAdapter<Payment> {
private List<Payment> items;
private int layoutResourceId;
private Context context;
public PayListAdapter(Context context, int layoutResourceId, List<Payment> items) {
super(context, layoutResourceId, items);
this.layoutResourceId = layoutResourceId;
this.context = context;
this.items = items;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
View row = convertView;
PaymentHolder holder = null;
LayoutInflater inflater = ((Activity) context).getLayoutInflater();
row = inflater.inflate(layoutResourceId, parent, false);
holder = new PaymentHolder();
holder.Payment = items.get(position);
holder.removePaymentButton = (ImageButton)row.findViewById(R.id.pay_removePay);
holder.removePaymentButton.setTag(holder.Payment);
holder.name = (TextView)row.findViewById(R.id.pay_name);
holder.value = (TextView)row.findViewById(R.id.pay_value);
row.setTag(holder);
setupItem(holder);
return row;
}
private void setupItem(PaymentHolder holder) {
holder.name.setText(holder.Payment.getName());
holder.value.setText(String.valueOf(holder.Payment.getValue()));
}
public static class PaymentHolder {
Payment Payment;
TextView name;
TextView value;
ImageButton removePaymentButton;
}
}
Here we list the Payment class items.
There are three most important elements here:
PayListAdapter constructor: sets some private fields and calls superclass constructor. It also gets the List of Payment objects. Its implementation is obligatory.
PaymentHolder: static class that holds references to all views that I have to set in this list item. I also keep the Payment object that references to this particular item in list. I set it as tag for ImageButton, that will help me to find the Payment item on list, that user wanted to remove
Overriden getView method: called by superclass. Its goal is to return the single List row. We create its fields and setup their values and store them in static holder. Holder then is put in row’s tag element. Note that there is a performance issue, as the row is being recreated each time it is displayed. I used to add some flag in holder like isCreated, and set it to true after row was already created. then you can add if statement and read tag’s holder instead of creating it from scratch.
Payment.java is quite simple as for now and it looks a bit like BasicNameValuePair:
public class Payment implements Serializable {
private String name = "";
private double value = 0;
public Payment(String name, double value) {
this.setName(name);
this.setValue(value);
}
...
}
There are additional gets and sets for each private field not shown.
3. Add ListView to the activity layout xml file
In its simpliest form, it will be enough to add this view to activity layout:
<ListView
android:id="#+id/EnterPays_PaysList"
android:layout_width="fill_parent"
android:layout_height="wrap_content">
</ListView>
4. Set up adapter to this list view in Activity Java code
In order to display items in ListView you need to set up its adapter and map it to some other ArrayList of Payment objects (as I am extending an Array adapter here). Here is code that is responsible for binding adapter to editPersonData.getPayments() ArrayList:
PayListAdapter adapter = new PayListAdapter(AddNewPerson.this, R.layout.pay_list_item, editPersonData.getPayments());
ListView PaysListView = (ListView)findViewById(R.id.EnterPays_PaysList);
PaysListView.setAdapter(adapter);
5. Adding / removing items to ListView (and its adapter)
Adapter is handled just like any other ArrayList, so adding new element to it is as simple as:
Payment testPayment = new Payment("Test", 13);
adapter.add(testPayment);
adapter.remove(testPayment);
6. Handle Remove Payment button click event
In an activity’s code, where ListView is displayed, add public method that will handle remove button click action. The method name has to be exactly the same as it was in pay_list_item.xml:
android:onClick="removePayOnClickHandler"
The method body is as follows:
public void removePayOnClickHandler(View v) {
Payment itemToRemove = (Payment)v.getTag();
adapter.remove(itemToRemove);
}
The Payment object was stored in ImageButton’s Tag element. Now it is enough to read it from Tag, and remove this item from the adapter.
7. Incorporate remove confirmation dialog window
Probably you need also make sure that user intentionally pressed the remove button by asking him additional question in confirmation dialog.
Dialogue
a) Create dialog’s id constant
This is simply dialog’s ID. it should be unique among any other dialog window that is handled by current activity. I set it like that:
protected static final int DIALOG_REMOVE_CALC = 1;
protected static final int DIALOG_REMOVE_PERSON = 2;
b) Build dialog
I use this method to build dialog window:
private Dialog createDialogRemoveConfirm(final int dialogRemove) {
return new AlertDialog.Builder(getApplicationContext())
.setIcon(R.drawable.trashbin_icon)
.setTitle(R.string.calculation_dialog_remove_text)
.setPositiveButton(R.string.calculation_dialog_button_ok, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int whichButton) {
handleRemoveConfirm(dialogRemove);
}
})
.setNegativeButton(R.string.calculation_dialog_button_cancel, null)
.create();
}
AlertDialog builder pattern is utilized here. I do not handle NegativeButton click action – by default the dialog is just being hidden. If dialog’s confirm button is clicked, my handleRemoveConfirm callback is called and action is performed based on dialog’s ID:
protected void handleRemoveConfirm(int dialogType) {
if(dialogType == DIALOG_REMOVE_PERSON){
calc.removePerson();
}else if(dialogType == DIALOG_REMOVE_CALC){
removeCalc();
}
}
c) Show Dialog
I show dialog after my remove button click. The showDialog(int) is Android’s Activity’s method:
OnClickListener removeCalcButtonClickListener = new OnClickListener() {
public void onClick(View v) {
showDialog(DIALOG_REMOVE_CALC);
}
};
the showDialog(int) method calls onCreateDialog (also defined in Activity’s class). Override it and tell your app what to do if the showDialog was requested:
#Override
protected Dialog onCreateDialog(int id) {
switch (id) {
case DIALOG_REMOVE_CALC:
return createDialogRemoveConfirm(DIALOG_REMOVE_CALC);
case DIALOG_REMOVE_PERSON:
return createDialogRemoveConfirm(DIALOG_REMOVE_PERSON);
}
}
Take a look at this blog post I wrote on exactly this matter:
Create custom ArrayAdapter
There are comments that explain every action I make in the adapter.
Here is the explanation in short:
So lets for example take a row where you want to place a CheckBox, ImageView
and a TextView while all of them are clickable. Meaning that you can click the
row it self for going to another Actvity for more details on the row, check its
CheckBox or press the ImageView to perform another operation.
So what you should do is:
1. First create an XML layout file for your ListView row:
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal" >
<CheckBox
android:id="#+id/cbCheckListItem"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="10dp" />
<TextView
android:id="#+id/tvItemTitle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="item string" />
<ImageView
android:id="#+id/iStatus"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:clickable="true"
android:contentDescription="#drawable/ic_launcher"
android:src="#drawable/ic_launcher" />
</LinearLayout>
2. Second in your java code define a ViewHolder, a ViewHolder
is designed to hold the row views and that way operating more quickly:
static class ViewHolder
{
TextView title;
CheckBox checked;
ImageView changeRowStatus;
}
3. Now we have to define CustomArrayAdapter, using the array adapter
we can define precisely what is the desired output for each row based on the content of this
row or it’s position. We can do so by overriding the getView method:
private class CustomArrayAdapter extends ArrayAdapter<RowData>
{
private ArrayList<RowData> list;
//this custom adapter receives an ArrayList of RowData objects.
//RowData is my class that represents the data for a single row and could be anything.
public CustomArrayAdapter(Context context, int textViewResourceId, ArrayList<RowData> rowDataList)
{
//populate the local list with data.
super(context, textViewResourceId, rowDataList);
this.list = new ArrayList<RowData>();
this.list.addAll(rowDataList);
}
public View getView(final int position, View convertView, ViewGroup parent)
{
//creating the ViewHolder we defined earlier.
ViewHolder holder = new ViewHolder();)
//creating LayoutInflator for inflating the row layout.
LayoutInflater inflator = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
//inflating the row layout we defined earlier.
convertView = inflator.inflate(R.layout.row_item_layout, null);
//setting the views into the ViewHolder.
holder.title = (TextView) convertView.findViewById(R.id.tvItemTitle);
holder.changeRowStatus = (ImageView) convertView.findViewById(R.id.iStatus);
holder.changeRowStatus.setTag(position);
//define an onClickListener for the ImageView.
holder.changeRowStatus.setOnClickListener(new OnClickListener()
{
#Override
public void onClick(View v)
{
Toast.makeText(activity, "Image from row " + position + " was pressed", Toast.LENGTH_LONG).show();
}
});
holder.checked = (CheckBox) convertView.findViewById(R.id.cbCheckListItem);
holder.checked.setTag(position);
//define an onClickListener for the CheckBox.
holder.checked.setOnClickListener(new OnClickListener()
{
#Override
public void onClick(View v)
{
//assign check-box state to the corresponding object in list.
CheckBox checkbox = (CheckBox) v;
rowDataList.get(position).setChecked(checkbox.isChecked());
Toast.makeText(activity, "CheckBox from row " + position + " was checked", Toast.LENGTH_LONG).show();
}
});
//setting data into the the ViewHolder.
holder.title.setText(RowData.getName());
holder.checked.setChecked(RowData.isChecked());
//return the row view.
return convertView;
}
}
4. Now you need to set this adapter, as the adapter of your ListView.
this ListView can be created in java or using an XML file, in this case I’m using a list that was
defined in the XML file using the “list” id:
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_layout);
ListView list = (ListView)findViewById(R.id.list);
CustomArrayAdapter dataAdapter = new CustomArrayAdapter(this, R.id.tvItemTitle, rowDataList);
list.setAdapter(dataAdapter);
}
5. Finally if we want to be able to press the row it self and not only a certain view in it
we should assign an onItemClickListener to the ListView:
list.setOnItemClickListener(new OnItemClickListener()
{
public void onItemClick(AdapterView<?> parent, View view,int position, long id)
{
Toast.makeText(activity, "row " + position + " was pressed", Toast.LENGTH_LONG).show();
}
});
First, the way of adding listeners in xml using onClick="function" is deprecated. You need a ViewHolder class to link the button in the xml to your java code. Then you can implement onClickListener for that.
Inside your getView() implementation of CustomAdapter, you can try like below.
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder;
if (convertView == null) {
convertView = inflater.inflate(R.layout.xxxxx, null);
holder = new ViewHolder();
holder.invite = (Button) convertView.findViewById(R.id.button);
} else {
holder = (ViewHolder) convertView.getTag();
}
final int pos = position;
holder.button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
handleClick(pos);
}
});
}
class ViewHolder {
Button button;
}

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