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Add custom listview to a fragment

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();
}

How to correctly implement a custom listview with images using Picasso library?

I created a custom listview layout with images which are loaded from web like this:
http://i.stack.imgur.com/l8ZOc.png
It works fine when scrolling down. However, when you scroll down, the previous items go out of screen then destroyed. When you try to scroll up again, it gets loaded again (from cache, faster but not instant) which causes a delay and it is not fluent as it should be.
1.Is there an example of how to do this properly?
2.Is there a way to prevent listview items being destroyed when they are out of screen?
3.If so, will it cause problems to keep too many items?
Bellow is my code:
MenuAdapter:
public class MenuAdapter extends BaseAdapter{
Context context;
List<MyMenuItem> menuItems;
MenuAdapter(Context context, List<MyMenuItem> menuItems) {
this.context = context;
this.menuItems = menuItems;
}
#Override
public int getCount() {
return menuItems.size();
}
#Override
public Object getItem(int position) {
return menuItems.get(position);
}
#Override
public long getItemId(int position) {
return menuItems.indexOf(getItem(position));
}
private class ViewHolder {
ImageView ivMenu;
TextView tvMenuHeader;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder = null;
LayoutInflater mInflater = (LayoutInflater) context.getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
if (convertView == null) {
convertView = mInflater.inflate(R.layout.menu_item, null);
holder = new ViewHolder();
holder.tvMenuHeader = (TextView) convertView.findViewById(R.id.tvMenuHeader);
holder.ivMenu = (ImageView) convertView.findViewById(R.id.ivMenuItem);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
MyMenuItem row_pos = menuItems.get(position);
Picasso.with(context)
.load(row_pos.getItem_image_url())
.into(holder.ivMenu);
holder.tvMenuHeader.setText(row_pos.getItem_header());
Log.e("Test", "headers:" + row_pos.getItem_header());
return convertView;
}
}
MyMenuItem:
public class MyMenuItem {
private String item_header;
private String item_image_url;
public MyMenuItem(String item_header, String item_image_url){
this.item_header=item_header;
this.item_image_url=item_image_url;
}
public String getItem_header(){
return item_header;
}
public void setItem_header(String item_header){
this.item_header=item_header;
}
public String getItem_image_url(){
return item_image_url;
}
public void setItem_image_url(String item_image_url){
this.item_image_url=item_image_url;
}
}
MainActivity:
public class MyActivity extends Activity implements AdapterView.OnItemClickListener {
List<MyMenuItem> menuItems;
ListView myListView;
JSONArray jsonArray;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_my);
Bundle extras = getIntent().getExtras();
if(extras!=null){
try{
jsonArray = new JSONArray(extras.getString("Data"));
}catch (Exception e){
e.printStackTrace();
}
}
menuItems = new ArrayList<MyMenuItem>();
for (int i = 0; i < jsonArray.length(); i++) {
try {
MyMenuItem item = new MyMenuItem(jsonArray.getJSONObject(i).getString("title"), jsonArray.getJSONObject(i).getString("imageURL"));
menuItems.add(item);
}catch (Exception e){
e.printStackTrace();
}
}
myListView = (ListView) findViewById(R.id.list);
MenuAdapter adapter = new MenuAdapter(this, menuItems);
myListView.setAdapter(adapter);
myListView.setOnItemClickListener(this);
}
}
MenuItem.xml:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<ImageView
android:id="#+id/ivMenuItem"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:scaleType="center"
android:src="#drawable/em" />
<TextView
android:id="#+id/tvMenuHeader"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#55000000"
android:paddingBottom="15dp"
android:paddingLeft="10dp"
android:paddingRight="10dp"
android:paddingTop="15dp"
android:textColor="#android:color/white"
android:layout_gravity="left|top"
android:layout_alignBottom="#+id/ivMenuItem"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_alignParentRight="true"
android:layout_alignParentEnd="true" />
</RelativeLayout>

1. Is there an example of how to do this properly?
Your code looks pretty close to perfect. The Adapter's getView method is usually the critical path to optimize. Compare for example Picasso's own example SampleListDetailAdapter.java. The important points it (as well as your code) does
check for & re-use already inflated views, inflation is expensive.
use ViewHolder so you don't have to call findViewById every time. Not terribly expensive on simple views. Also cached afaik.
Picasso.with(context).load(url)... each time you need to display an image. This should finish instantly but still use caches and other magic.
There are some minor optimizations you can add, but I doubt that there are noticeable or even measurable changes:
pure style change: use BaseAdapter#getItem(position). This method
exists for you only. The framework doesn't use it.
#Override
public MyMenuItem getItem(int position) { // << subclasses can use subtypes in overridden methods!
return menuItems.get(position);
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
...
MyMenuItem row_pos = getItem(position);
Use a sane id method
#Override
public long getItemId(int position) {
return menuItems.indexOf(getItem(position));
}
is equivalent to
#Override
public long getItemId(int position) {
return position;
}
but now infinitely faster. indexOf(Object) scales really badly with the number of objects.
Cache objects that don't change:
MenuAdapter(Context context, List<MyMenuItem> menuItems) {
this.mLayoutInflater = LayoutInflater.from(content);
this.mPicasso = Picasso.with(context);
}
..
#Override
public View getView(int position, View convertView, ViewGroup parent) {
if (convertView == null) {
convertView = mInflater.inflate(R.layout.menu_item, null);
...
mPicasso
.load(row_pos.getItem_image_url())
.into(holder.ivMenu);
2. Is there a way to prevent listview items being destroyed when they are out of screen?
No(*).
..(*) well you can essentially cache the result of getView e.g. in LruCache(position, View) or LruCache(MyMenuItem, View), then don't touch the convertView - they need to remain unconverted or you would kill those views in your cache. Also
#Override
public int getItemViewType(int position) {
return Adapter.IGNORE_ITEM_VIEW_TYPE;
}
seemed to be required because the standard adapter using code assumes that views it removes from visibility are gone. They are not and messing with them messes with your cache and caused weird display problems for me.
3. If so, will it cause problems to keep too many items?
Yes. This behavior is not intendend / expected. There is also more or less nothing you gain. You might be able to save you the call to holder.tvMenuHeader.setText(). Likewise the one to Picasso but both of them should complete instantly. Picasso should have your image cached already. By caching all Views you essentially add another cache that also contains all the images. I would rather check that the picasso cache works as intended and holds most items. The only reason you may want to do it with view caching is for cases that require complicated setup of the view, so it becomes worth caching the completely constructed view rather than just some content parts.
Profile
Profiling can actually tell you where you can / need / should improve. The first to look at IMO is traceview. You'll see if code blocks the main thread which results in choppy list scrolling. If you're doing complicated views and you see that the draw methods are executed most of the time, profile them as well.
http://www.curious-creature.org/docs/android-performance-case-study-1.html
http://blog.venmo.com/hf2t3h4x98p5e13z82pl8j66ngcmry/performance-tuning-on-android
http://www.vogella.com/tutorials/AndroidTools/article.html

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.

ListView with images only

I was just asking myself if there was a way of making a ListView without any texts. I've only found ListViews with images + texts, and that exactly what i dont want. I just want to add a lot of images like in a list and don't want to make it with ImageView because that makes my app crash. Also, i dont want my app to lag. Thanks!
this is what i got in my activity_main.xml
<ListView
android:id="#+id/listview"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
/>
and i found this from another post that actually helped me, but it doesnt display all images
public class MainActivity extends Activity {
// Array of integers points to images stored in /res/drawable-hdpi/
int[] vehs = new int[]{
R.drawable.veh1,
R.drawable.veh2,
R.drawable.veh3,
R.drawable.veh4,
R.drawable.veh5,
R.drawable.veh6,
R.drawable.veh7,
R.drawable.veh8,
R.drawable.veh9,
R.drawable.veh10,
R.drawable.veh11,
R.drawable.veh12,
R.drawable.veh13,
R.drawable.veh14,
R.drawable.veh15,
R.drawable.veh16,
R.drawable.veh17,
R.drawable.veh18,
R.drawable.veh19,
R.drawable.veh20,
R.drawable.veh21,
R.drawable.veh22,
R.drawable.veh23,
R.drawable.veh24,
R.drawable.veh25,
R.drawable.veh26,
R.drawable.veh27,
R.drawable.veh28,
R.drawable.veh29,
R.drawable.veh30,
R.drawable.veh31,
R.drawable.veh32,
R.drawable.veh33,
R.drawable.veh34,
R.drawable.veh35,
R.drawable.veh36,
};
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Each row in the list stores country name, currency and flag
List<HashMap<String,String>> aList = new ArrayList<HashMap<String,String>>();
for(int i=0;i<10;i++){
HashMap<String, String> hm = new HashMap<String,String>();
hm.put("vehs", Integer.toString(vehs[i]) );
aList.add(hm);
}
// Keys used in Hashmap
String[] from = { "vehs","txt","cur" };
// Ids of views in listview_layout
int[] to = { R.id.vehs,R.id.txt,R.id.cur};
// Instantiating an adapter to store each items
// R.layout.listview_layout defines the layout of each item
SimpleAdapter adapter = new SimpleAdapter(getBaseContext(), aList, R.layout.listview_layout, from, to);
// Getting a reference to listview of main.xml layout file
ListView listView = ( ListView ) findViewById(R.id.listview);
// Setting the adapter to the listView
listView.setAdapter(adapter);
}
}
Didn't edit all the code, so you might find some things confusing xD

The way ListView displays data is by using an adapter. The adapter takes your data, inserts it into a custom view, and then adds it to the list.
To build a fast images ListView, the first thing you'd want to do is to add Picasso to your project. This library will automatically download and cache your images, handle ImageView recycling, and more.
The next thing you'd want to do is to write your item view. If you want an images-only list, the view could be as simple as:
<!-- res/layout/list_item.xml -->
<?xml version="1.0" encoding="utf-8"?>
<ImageView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="?android:attr/listPreferredItemHeight" />
Next, you want to create your adapter. It accepts a List<String> of image URLs as an input, builds the items and inserts them to the ListView.
public class ImageListAdapter extends ArrayAdapter<String> {
List<String> items;
public ImageListAdapter(Context context, int resource, List<String> items) {
super(context, resource, items);
this.items = items;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
if (convertView == null) {
LayoutInflater inflater = LayoutInflater.from(getContext());
convertView = inflater.inflate(R.layout.list_item, null);
}
Picasso.with(getContext())
.load(items.get(position))
.into((ImageView) convertView);
return convertView;
}
}
Read the Picasso library documentation if you want to add more options such as image placeholders, transformations, and more.
Finally, to use the adapter on your ListView, add this to your activity's onCreate method:
List<String> images = new ArrayList<String>();
images.add("http://hometowncolumbia.files.wordpress.com/2007/12/lol-cats-dont-look-behind-cat.jpg");
images.add("http://i232.photobucket.com/albums/ee245/topswing/cat-lol.jpg");
listView = (ListView)findViewById(R.id.myListView);
listView.setAdapter(new ImageListAdapter(this, R.layout.list_item, images))
In a real application though, you'd probably want to load the image list from your server. You'd need to use an AsyncTask for that.

Don't make things difficult, the solution is simple in the classic 3 steps
Step 1:
Make a RelativeLayout in XML. Move the image to desired position (always to center, but you can choose if left or right) and change layout_height to wrap_content
Step 2:
Create a custom adapter for ListView, if you do this, you'll be able to all any layout as an item
public class ImagesAdapter extends ArrayAdapter<String> {
private Activity mContext;
private ArrayList<Bitmap> mImages;
public ImagesAdapter(Activity context, ArrayList<String> listOfValues, ArrayList<Bitmap> images) {
//The listOfValues is used when you make item click to get value
//Each image must to have a text value
super(context, R.layout.yourlayout, listOfValues);
mContext = context;
mImages = images;
}
#Override
public void getView(int position, View convertView, ViewGroup parent) {
LayoutInflater inflater = mContext.getLayoutInflater();
View returnView = inflater.inflate(R.layout.yourlayout, null);
ImageView imageView = (ImageView) returnView.findViewById(R.id.yourimageid);
imageView.setImageBitmap(mImages.get(position));
return returnView;
}
}
Step 3:
Implement in your code
ImagesAdapter adapter = new ImagesAdapter(this, myList, myImages);
mylistView.setAdapter(adapter);
myListView.setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
//volov = Values Of ListOfValues
String volov = (String) myListView.getItemPosition(position);
Log.i(TAG, "listOfValues is useful " + volov);
}
});

Change fragment visibility in runtime when the fragment was created using FragmentPagerAdapter

I'm trying to create my first Android app that looks like following: there is main activity with multiple fragments initialized by FragmentPagerAdapter. There is another activity (SettingsActivity) where I want to list all the fragment names and allow hiding some of them. To hide them I want to use the following:
FragmentManager fm=getFragmentManager();
Fragment myFragment=fm.findFragmentByTag("tag");
fm.beginTransaction().hide(myFragment).commit();
The problem is that I don't know fragment id or tag, not sure if they exist. How I can get them? Should I switch to XML definition to make it possible?
Adapter:
public class TabsPagerAdapter extends FragmentPagerAdapter {
public TabsPagerAdapter(FragmentManager fm) {
super(fm);
}
#Override
public Fragment getItem(int index) {
switch (index){
case 0:
return new CoverFragment();
case 1:
return new NumbersConverterFragment();
case 2:
return new TempConverterFragment();
case 3:
return new LengthConverterFragment();
case 4:
return new AreaConverterFragment();
case 5:
return new VolumeConverterFragment();
case 6:
return new WeightConverterFragment();
case 7:
return new SpeedConverterFragment();
}
return null;
}
#Override
public int getCount() {
return 8;
}
Main activity:
public class MainActivity extends FragmentActivity implements ActionBar.TabListener {
private ViewPager viewPager;
private TabsPagerAdapter tabsPagerAdapter;
private ActionBar actionBar;
#Override
protected void onCreate(Bundle savedInstanceState) {
String[] tabs={getString(R.string.title_section0), getString(R.string.title_section1),getString(R.string.title_section2)};
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
viewPager=(ViewPager) findViewById(R.id.pager);
actionBar=getActionBar();
tabsPagerAdapter=new TabsPagerAdapter(getSupportFragmentManager());
viewPager.setAdapter(tabsPagerAdapter);
actionBar.setHomeButtonEnabled(false);
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
for(String tab : tabs){
actionBar.addTab(actionBar.newTab().setText(tab).setTabListener(this));
}
viewPager.setOnPageChangeListener(new ViewPager.OnPageChangeListener() {
#Override
public void onPageSelected(int position) {
// on changing the page
// make respected tab selected
actionBar.setSelectedNavigationItem(position);
}
...
});
}
Fragment layout:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="#fbfdfb"
>
<TextView android:text="#string/celsius_" android:id="#+id/textView1"
android:layout_width="wrap_content" android:layout_height="wrap_content"></TextView>
<EditText android:text="" android:id="#+id/txtCelsius" android:layout_width="match_parent"
android:layout_height="wrap_content"></EditText>
<TextView android:text="#string/fahrenheit_" android:id="#+id/textView1"
android:layout_width="wrap_content" android:layout_height="wrap_content"></TextView>
<EditText android:text="" android:id="#+id/txtFahrenheit" android:layout_width="match_parent"
android:layout_height="wrap_content"></EditText>
<TextView android:text="#string/kelvin_" android:id="#+id/textView1"
android:layout_width="wrap_content" android:layout_height="wrap_content"></TextView>
<EditText android:text="" android:id="#+id/txtKelvin" android:layout_width="match_parent"
android:layout_height="wrap_content"></EditText>
</LinearLayout>
Fragment class:
public class TempConverterFragment extends Fragment {
EditText txtCelsius, txtFahrenheit, txtKelvin;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.temp_converter_fragment, container, false);
txtCelsius = (EditText) rootView.findViewById(R.id.txtCelsius);
txtFahrenheit = (EditText) rootView.findViewById(R.id.txtFahrenheit);
txtKelvin = (EditText) rootView.findViewById(R.id.txtKelvin);
...
}
...
}
Thanks in advance.

If SettingsActivity is not the Activity holding the FragmentPagerAdapter, then you would have to re-create all the fragments. The nature of a fragment is to be closely tied to it's activity.
If SettingsActivity is the Activity holding the FragmentPagerAdapter, then As I recall, FragmentPagerAdapter will initialize all the 8 fragments as soon as possible to have them ready when you swipe, unlike FragmentStatePagerAdapter. This means that you should (I think) be able to create each fragment in the constructor TabsPagerAdapter and keeping a reference to them, which you could access using getter methods on the TabsPagerAdapter.
Here is an example of how to get easy access to your pageradapter fragments:
public class DisplayPagerAdapter extends FragmentStatePagerAdapter {
private static final String TAG = "DisplayPagerAdapter";
SparseArray<DisplayFragment> registeredFragments = new SparseArray<DisplayFragment>();
#Inject DisplayCoreModule display;
public DisplayPagerAdapter(FragmentManager fm) {
super(fm);
}
#Override
public int getCount() {
return (display != null && display.getPagesCount() > 0) ? display.getPagesCount() : 1;
}
#Override
public int getItemPosition(Object object) {
return POSITION_NONE;
}
#Override
public Fragment getItem(int position) {
Log.d(TAG, "getItem " + position);
return DisplayFragment.newInstance(position);
}
#Override
public CharSequence getPageTitle(int position) {
if (display != null && display.getPagesCount() > 0) {
return "Side " + (position+1);
} else {
return super.getPageTitle(position);
}
}
#Override
public Object instantiateItem(ViewGroup container, int position) {
Log.d(TAG, "instantiateItem " + position);
DisplayFragment fragment = (DisplayFragment) super.instantiateItem(container, position);
registeredFragments.put(position, fragment);
return fragment;
}
#Override
public void destroyItem(ViewGroup container, int position, Object object) {
Log.d(TAG, "destroyItem " + position);
registeredFragments.remove(position);
super.destroyItem(container, position, object);
}
public Fragment getRegisteredFragment(int position) {
return registeredFragments.get(position);
}
public SparseArray<DisplayFragment> getRegisteredFragments() {
return registeredFragments;
}
}
Now if you implement this usage of registeredFragments , you can call tabsPagerAdapter.getRegisteredFragment(2) to get your TempConverterFragment.
SparseArray<DisplayFragment> should be SparseArray<Fragment> in your case
Now this does not solve the your SettingsActivity problem. But if I understand you correctly, then adding the fragments your want directly in the layout XML of SettingsActivity would make sense. Then it would be easy to temporarily hide the fragments or whatever using:
FragmentManager fm=getFragmentManager();
Fragment myFragment=fm.findFragmentById(R.id.frag_tempconverter)
fm.beginTransaction().hide(myFragment).commit();
Notice the use of findFragmentById. The tag is usually used for dynamically added fragments (atleast in my mind). The findFragmentById will surely return a fragment if it is defined in the XML layout but just to be clear, it will be a new instance of the fragment.
To address your questions:
What if I move the fragments to the main activity XML? Won't it make things simpler
Do not think so, the updated answer shows how to easily access the fragments (from within your main activity).
Though not sure I can use FragmentManager in SettingsActivity
Sure you can. You can add new fragments, access available fragments (from predefined XML using findById or dynamically added using findByTag). You cannot, however, access the same instance of the fragment as was kept by your main activity.
To share information between the fragments and the two activities, you need to persist the state of your fragments somehow (which is a different topic).
All in all I think you are on the right path, you just need to combine the right pieces of the puzzle :)