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Android Recyclerview item side by side

I have recycler-view with items in it and can be scrolled vertically. Currently what i achieved is items are added one after another like a list. By i need to place them side by side.
Like the image below
And my output is
My recycler-view setup code:
topicAdapter = new TopicAdapter(topicList, getActivity());
topicListView.setLayoutManager(new LinearLayoutManager(getActivity()));
topicListView.setAdapter(topicAdapter);
and adapter code is:
public class TopicAdapter extends RecyclerView.Adapter<TopicAdapter.CategoryViewHolder> {
private List<Topic> topicList;
Context context;
public TopicAdapter(List<Topic> topicList, Context context) {
this.topicList = topicList;
this.context = context;
}
#Override
public CategoryViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
//inflate the layout file
View groceryProductView = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_suggested_topics, parent, false);
CategoryViewHolder holder = new CategoryViewHolder(groceryProductView);
return holder;
}
#Override
public void onBindViewHolder(CategoryViewHolder holder, final int position) {
holder.txtview.setText(topicList.get(position).getName());
}
#Override
public int getItemCount() {
return topicList.size();
}
public class CategoryViewHolder extends RecyclerView.ViewHolder {
TextView txtview;
public CategoryViewHolder(View view) {
super(view);
txtview = view.findViewById(R.id.titleView);
}
}
}

I can suggest you with a simple solution but, you cant achieve complete requirement with this code. You'll get side by side.
Replace
topicListView.setLayoutManager(new LinearLayoutManager(getActivity()));
with
topicListView.setLayoutManager(new GridLayoutManager(getActivity(), 3));
// 3 denotes the number of rows per column

You can do this using Google's latest design component ChipGroup
Else you can use Flexbox-Layout by showing your tags in Grid Layout.
If you wish to go for Flexbox-Layout, check answer of avik

Add This
topicListView.setLayoutManager(new LinearLayoutManager(getActivity(), LinearLayoutManager.HORIZONTAL,false));

Use StaggeredGridLayoutManager for recyclerview

I think a good way to do this is by using Material Choice Chips, you can learn how to use them here. You can then use a ChipGroup to group them and allow them to flow across multiple lines.
However, to solve your question at hand, you can use a GridLayoutManager and then supply a SpanSizeLookup.

How RecyclerView concept works on android?

I have created a basic app using RecyclerView and CardView from get tutorials from websites.
App is working fine and I have some confusion.(I am showing my whole code here)
confusion is that how code works step by step. So please clear my concept on it.
Basic Structure of my App :
I have created a row_data_layout xml file to bind on recycler_view.
Created an Data class file (Here I have defined my variable that I used in App).
Created an Adapter file (here I want to clear how it works step by step first which class gets called and why?).
Bind Data to RecyclerView on MainActivity file.
row_data_layout.xml file:
<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="#+id/CardView"
android:paddingBottom="16dp"
android:layout_marginBottom="16dp">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<TextView
android:id="#+id/txt_name"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
android:text="Large Text"
android:textAppearance="?android:attr/textAppearanceLarge" />
</LinearLayout>
</android.support.v7.widget.CardView>
Data Class File:
public class Data {
public String Name;
Data(String Name)
{
this.Name=Name;
}
}
Data_Adapter Class file:
public class Data_Adapter extends RecyclerView.Adapter<Data_Adapter.View_holder> {
List<Data> list = Collections.emptyList();
Context context;
public Data_Adapter(List<Data> list, Context context) {
this.list = list;
this.context = context;
}
#Override
public Data_Adapter.View_holder onCreateViewHolder(ViewGroup parent, int viewType) {
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.row_data_layout,parent,false);
View_holder holder=new View_holder(v);
return holder;
}
#Override
public void onBindViewHolder(Data_Adapter.View_holder holder, int position) {
holder.name.setText(list.get(position).Name);
}
#Override
public int getItemCount() {
return list.size();
}
#Override
public void onAttachedToRecyclerView(RecyclerView recyclerView) {
super.onAttachedToRecyclerView(recyclerView);
}
public class View_holder extends RecyclerView.ViewHolder{
CardView cv;
TextView name;
public View_holder(View itemView) {
super(itemView);
cv = (CardView) itemView.findViewById(R.id.CardView);
name = (TextView) itemView.findViewById(R.id.txt_name);
}
}
}
MainActivity File:
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
List<Data> data = fill_data();
RecyclerView recyclerView = (RecyclerView) findViewById(R.id.recyclerView);
Data_Adapter adapter = new Data_Adapter(data,getApplicationContext());
recyclerView.setAdapter(adapter);
recyclerView.setLayoutManager(new LinearLayoutManager(this));
}
public List<Data> fill_data()
{
List<Data> data = new ArrayList<>();
data.add(new Data("Bred Pit"));
data.add(new Data("Leonardo"));
return data;
}
}

Once you have a basic understanding of how a RecyclerView.Adapter works, it would make sense to take a deeper dive into the documentation.
What the adapter does is keep a pool of inflated views (this can be as many different types of ViewHolder as you would like) that it populates with the data you supply. When the adapter does not have an empty view in the pool it creates a new one.
When a view is attached to the RecyclerView, it is removed from the pool, and when it is detached (scrolls beyond view, to some distance), it is added back to the pool of empty views--this is why it is important to reset everything when you populate your ViewHolders.
The onCreateViewHolder() function is where a new, empty view (wrapped by a RecyclerView.ViewHolder) is created and added to the pool.
The onBindViewHolder() function gets a view from the empty pool and populates this view using the data you supplied to the adapter.\
You can use the onViewRecycled() method to perform specific actions like setting an ImageView's bitmap to null (on detach) in order to reduce memory usage.
I don't normally override onAttachedToRecyclerView(), but if you need to do something specific when your adapter is associated with the RecyclerView, you would do it here.

RecyclerView add EmptyView

I'm trying to implement an EmptyView on my RecyclerView Adapter but I'm not getting any result.
I've followed this tutorial and this tip, but noone worked for me.
I've implemented:
if (viewType == EMPTY_VIEW) {
v = LayoutInflater.from(parent.getContext()).inflate(R.layout.empty_view, parent, false);
EmptyViewHolder evh = new EmptyViewHolder(v);
return evh;
}
v = LayoutInflater.from(parent.getContext()).inflate(R.layout.data_row, parent, false);
ViewHolder vh = new ViewHolder(v);
return vh;
But it doesn't let me compile because they are differents ViewHolder, because I've created two ViewHolder classes but they extends Recycler.ViewHolder so I don't get it...
I'm trying to do this because I've got a SearchView and I want when the list is empty it shows an EmptyView, I've got it doing it programmatically but I prefer to add like a layout because I don't know that much how to put TextViews and Buttons programmatically.
Also if I put
return dataList.size() > 0 ? dataList.size() : 1;
It gives to me error because index is 0.
I've debugged the viewType and always is 1, then it won't join the if condition...
Deep on Android I found this :
/**
* Return the view type of the item at <code>position</code> for the purposes
* of view recycling.
*
* <p>The default implementation of this method returns 0, making the assumption of
* a single view type for the adapter. Unlike ListView adapters, types need not
* be contiguous. Consider using id resources to uniquely identify item view types.
*
* #param position position to query
* #return integer value identifying the type of the view needed to represent the item at
* <code>position</code>. Type codes need not be contiguous.
*/
public int getItemViewType(int position) {
return 0;
}
But the thing is that no changes the value.
EDIT
I almost done it, I did this :
#Override
public int getItemViewType(int position) {
return list.size() > 0 ? list.size() : 1;
}
But sometimes it returns 0 when the size() is 0... I don't get it, I'm using this SearchView, and sometimes when I type a letter that doesn't matches with any item of the list it doesn't show and sometimes it does...
Also other thing that happens is that when the layout popups it shows on the left of the screen when I put that is on center, but I think it's problem with RecyclerView because the layout puts inside of it.
RecyclerView layout :
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="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"
android:id="#+id/rtpew"
android:layout_centerInParent="true"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
>
<LinearLayout android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="#+id/linearpew">
<android.support.v7.widget.RecyclerView
android:id="#+id/rv"
android:layout_width="match_parent"
android:layout_height="wrap_content"
/>
</LinearLayout>
</RelativeLayout>
And this is my emptylayout :
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_centerInParent="true">
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/ImageViewSearchFail"
android:src="#drawable/sadface"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:gravity="center_vertical"
android:layout_gravity="center"
android:textSize="#dimen/15dp"
android:layout_marginTop="4dp"
android:text="foo"
android:layout_below="#+id/ImageViewSearchFail"
android:layout_centerHorizontal="true" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/ButtonAddEntity"
android:text="foo"
android:background="?android:selectableItemBackground"
android:layout_centerVertical="true"
android:layout_centerHorizontal="true" />
</RelativeLayout>
The other way that I thought is to implement it programmatically as follow :
#Override
public boolean onQueryTextChange(String query) {
final ArrayList<List> filteredModelList = filter(mModel, query);
mAdapter.animateTo(filteredModelList);
rv.scrollToPosition(0);
if(query.isEmpty()){
//Here
}
return true;
}
And :
private ArrayList<List> filter(ArrayList<List> models, String query) {
query = query.toLowerCase();
final ArrayList<List> filteredModelList = new ArrayList<List>();
for (List model : models) {
final String text = model.getRedName().toLowerCase();
if (text.contains(query)) {
filteredModelList.add(model);
}
}
if (filteredModelList.size()<0) {
//HERE
}
else{
//Delete the views added
}
return filteredModelList;
}
PROBLEMS
-I only add the view using the #Jimeux answer but I'd like to do this on the Adapter, I got it, but not always shows the view even if the list is empty.
-At the time to put the emptyview.xml it puts inside of the RecyclerView then since I've put all of this xml at the center it shows on the right. I've tried to add the xml programmatically but it's like a chaos....

Since you need to handle two different kind of views, it would be easier to use an intermediate list of business object for more easily binding them with views. Idea is to have a kind of placeholder in your list for representing empty state. Defining an intermediate layer is extremely useful in this sense for allowing you to consider eventual changes to be applied to your list in future (e.g. adding you element types). Moreover in this way you can more clearly separate your business model from ui representation (for example you can implement methods returning ui settings based on internal status of model objects).
You can proceed as follows:
Define a dedicated abstract type for List items (e.g. ListItem) to wrap your business objects. Its implementation could be something like this:
public abstract class ListItem {
public static final int TYPE_EMPTY = 0;
public static final int TYPE_MY_OBJ = 1;
abstract public int getType();
}
Define a class for each of your List element type:
public class EmptyItem extends ListItem {
#Override
public int getType() {
return TYPE_EMPTY;
}
}
public class MyObjItem extends ListItem {
private MyObj obj;
public ContactItem(MyObj obj) {
this.obj = obj;
}
public MyObj getMyObj() {
return obj;
}
// here you can also add methods for simplify
// objects rendering (e.g. get background color
// based on your object internal status)
#Override
public int getType() {
return TYPE_MY_OBJ;
}
}
Create your list.
List<ListItem> mItems = new ArrayList<>();
if (dataList != null && dataList.size() > 0) {
for (MyObj obj : dataList) {
mItems.add(new MyObjItem(obj));
}
} else {
mItems.add(new EmptyItem());
}
This is the most important part of code. You have many options for creating this list. You can do it inside your RecyclerView Adapter or outside, but it's extremely important to properly handle eventual modifications to it. This is essential for exploiting Adapter notify methods. For example, if you create list within the Adapter, it should probably provide also methods for adding or removing your model items. For example:
public void addObj(MyObj obj) {
if (mItems.size() == 1 && mItems.get(0).getType() == ListItem.EMPTY_TYPE) {
mItems.clear();
}
mItems.add(new MyObjItem(obj));
notifyDataSetChanged();
}
Define an adapter for your RecyclerView, working on List defined at point 3. Here what is important is to override getItemViewType method as follows:
#Override
public int getItemViewType(int position) {
return mItems.get(position).getType();
}
Moreover, type of ViewHolder should be RecyclerView.ViewHolder (unless you decide to create an intermediate class even in this case).
Then you need to have two layouts and ViewHolder for empty and business obj items. Adapter methods should take care of this accordingly:
#Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
if (viewType == ListItem.TYPE_EMPTY) {
View itemView = mLayoutInflater.inflate(R.layout.empty_layout, parent, false);
return new EmptyViewHolder(itemView);
} else {
View itemView = mLayoutInflater.inflate(R.layout.myobj_layout, parent, false);
return new MyObjViewHolder(itemView);
}
}
#Override
public void onBindViewHolder(final RecyclerView.ViewHolder viewHolder, final int position) {
int type = getItemViewType(position);
if (type == ListItem.TYPE_EMPTY) {
EmptyItem header = (EmptyItem) mItems.get(position);
EmptyViewHolder holder = (EmptyViewHolder) viewHolder;
// your logic here... probably nothing to do since it's empty
} else {
MyObjItem event = (MyObjItem) mItems.get(position);
MyObjViewHolder holder = (MyObjViewHolder) viewHolder;
// your logic here
}
}
Of course, as I wrote at the beginning you don't need to strictly define intermediate types for ui representation (EmptyItem and MyObjItem). You can even just use MyObj type and create a specific configuration for it that represent an empty placeholder. This approach is probably not the best in case in future you need to make your logic more complex by including for example new list item types.

Follow the below steps one by one
1). Since you have two types of views for your RecyclerView item, your adapter declaration should look like this a generic one
public class YourAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder>
and your ViewHolders for both listview item and empty view should extend RecyclerView.ViewHolder like this
static class ListItemViewHolder extends RecyclerView.ViewHolder {
public ListItemViewHolder(View itemView) {
super(itemView);
// initialize your views here for list items
}
}
static class EmptyViewViewHolder extends RecyclerView.ViewHolder {
public EmptyViewViewHolder(View itemView) {
super(itemView);
// initialize your views here for empty list
}
}
2). You have to Override getItemCount() and getItemViewType()
#Override
public int getItemCount() {
return yourList.size() > 0 ? yourList.size() : 1;// if size of your list is greater than 0, you will return your size of list otherwise 1 for the empty view.
}
#Override
public int getItemViewType(int position) {
if (yourList.size() == 0) {
return VIEW_TYPE_EMPTY;
}
return position;
}
3). Your onCreateViewHolder() will look alike this now
#Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
if (viewType == VIEW_TYPE_EMPTY) {
return new EmptyViewViewHolder(mLayoutInflater
.inflate(R.layout.empty_view_layout, parent, false));
} else {
return new ListItemViewHolder(mLayoutInflater
.inflate(R.layout.row_list_item, parent, false));
}
}
4). Same check you have to apply in your onBindViewHolder() as well
#Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
if (getItemViewType(position) == VIEW_TYPE_EMPTY) {
EmptyViewViewHolder emptyViewViewHolder = (EmptyViewViewHolder) holder;
// set values for your empty views
} else {
ListItemViewHolder listItemViewHolder = (ListItemViewHolder) holder;
// set values for your list items
}
}
5). At last Override your SearcView.setOnQueryTextListener()
searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
#Override
public boolean onQueryTextSubmit(String query) {
return false;
}
#Override
public boolean onQueryTextChange(String newText) {
currentSearchKeyword = newText.trim();
if(currentSearchKeyword.iseEmpty()){
yourList.clear();
yourAdapter.notifyDataSetChanged();
}else{
// there will two cases again 1). If your currentSearchKeyword matchces with list results, add that items to your list and notify your adapter. 2) If the currentSearchKeyword doesn't matched with list results, clear your list and notify your adapter;
}
return false;
}
});
Hope it will help you, let me know if any issues.

The compilation error probably results because of you extending RecyclerView.Adapter with your main ViewHolder as the generic argument.
You should make it like
YourAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder>
And then cast your ViewHolders appropriately (you can reuse getViewType(position) here). Be sure to switch the ViewHolder type in your methods as well.

If I were you, I wouldn't put the empty view in the adapter at all. Put it under your linearpew layout that's holding the RecyclerView and hide/show it as your data changes. You can easily add a loading view, error view, etc. with this setup too.
Here's a bit of simplified code from one of my apps to give you some ideas. #Bind comes from Butter Knife if you're not familiar with it. You may also want to check out Jake Wharton's u2020 project for more RecyclerView ideas.
//fragment_layout.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<FrameLayout android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:id="#+id/content">
</FrameLayout>
<include layout="#layout/status_views" />
</RelativeLayout>
//status_views.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center"
android:orientation="vertical">
<LinearLayout style="#style/ListStatusView"
android:id="#+id/empty_view"/>
<LinearLayout style="#style/ListStatusView"
android:id="#+id/error_view"/>
<LinearLayout style="#style/ListStatusView"
android:id="#+id/loading_view"
android:padding="30dp"/>
</LinearLayout>
//MyFragment.java
#Bind(R.id.content) protected ViewGroup contentView;
#Bind(R.id.loading_view) protected ViewGroup loadingView;
#Bind(R.id.empty_view) protected ViewGroup emptyView;
#Bind(R.id.error_view) protected ViewGroup errorView;
#Bind({R.id.loading_view, R.id.error_view, R.id.empty_view, R.id.content})
protected List<ViewGroup> stateViews;
protected void activateView(View view) {
for (ViewGroup vg : stateViews)
vg.setVisibility(View.GONE);
view.setVisibility(VISIBLE);
}
#Override
public void onActivityCreated(#Nullable Bundle state) {
super.onActivityCreated(state);
if (state == null) {
activateView(loadingView);
loadData();
} else if (data.isEmpty())
activateView(emptyView);
else
activateView(contentView);
}
Edit: Here's a simplified version without Butter Knife.
private ViewGroup contentView;
private ViewGroup emptyView;
#Override
protected void onCreate(#Nullable Bundle state) {
super.onCreate(state);
setContentView(R.layout.activity_main);
contentView = (ViewGroup) findViewById(R.id.content_view);
emptyView = (ViewGroup) findViewById(R.id.empty_view);
}
#Override
public boolean onQueryTextChange(String query) {
final ArrayList<List> filteredModelList = filter(mModel, query);
mAdapter.animateTo(filteredModelList);
rv.scrollToPosition(0);
if(query.isEmpty()){
contentView.setVisibility(View.GONE);
emptyView.setVisibility(View.VISIBLE);
} else {
contentView.setVisibility(View.VISIBLE);
emptyView.setVisibility(View.GONE);
}
return true;
}
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/rtpew"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_centerInParent="true">
<LinearLayout
android:id="#+id/content_view"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<android.support.v7.widget.RecyclerView
android:id="#+id/rv"
android:layout_width="match_parent"
android:layout_height="wrap_content"/>
</LinearLayout>
<RelativeLayout android:id="#+id/empty_view">
<ImageView android:src="#drawable/sadface"/>
<TextView android:text="foo"/>
<Button android:id="#+id/ButtonAddEntity"/>
</RelativeLayout>
</RelativeLayout>

Here is what you can try:
1. Replace
EmptyViewHolder evh = new EmptyViewHolder(v);
with
RecyclerView.ViewHolder evh = new EmptyViewHolder(v);
This is probably why the compilation fails.
2. Replace
#Override
public int getItemViewType(int position) {
return list.size() > 0 ? list.size() : 1;
}
with
#Override
public int getItemViewType(int position) {
return list.get(position) != null ? 1 : 0;
}
For this to work, you must insert a null object whenever you want to show an EmptyView:
int progressPosition = list.size();
list.add(null);
adapter.notifyItemInserted(progressPosition);
and remove the null object when you want to hide the EmptyView:
int progressPosition = existingList.size() - 1;
existingList.remove(progressPosition);
adapter.notifyItemRemoved(progressPosition);
Also, you must modify your onCreateViewHolder() method as follows:
#Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
if (viewType == 1) {
// inflate your default ViewHolder here ...
} else {
// inflate the EmptyViewHolder here
}
}
I believe we have discussed this before ... see this question for a detailed discussion on this.
3. Instead of using a SearchView, consider using an AutoCompleteTextView with a Filter. This may be easier to integrate with your RecyclerView's Adapter. See this answer for an example of this.
I will update this answer as I understand your question better ... do try this and update me.

android:entries in recyclerview

I have used listview with entries attribute like below :
<ListView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:entries="#array/fi"/>
Now i am converting it to RecyclerView
<android.support.v7.widget.RecyclerView
android:id="#+id/rv"
android:layout_width="match_parent"
android:layout_height="match_parent" />
I want to know whether we have android:entries attribute in RecyclerView? Or any other attribute instead of entries?

As correctly explained in the other answers there isn't an attribute to fill the RecyclerView from xml. However using the Android Databinding you can create a similar attribute quite easily:
<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto">
<android.support.v7.widget.RecyclerView
android:layout_width="match_parent"
android:layout_height="match_parent"
app:entries="#{#stringArray/fi}"
app:layoutManager="android.support.v7.widget.LinearLayoutManager"/>
</layout>
Here the binding adapter definition:
import android.databinding.BindingAdapter;
public class RecyclerViewBindings {
#BindingAdapter("entries")
public static void entries(RecyclerView recyclerView, String[] array) {
recyclerView.setAdapter(new SimpleArrayAdapter(array));
}
static class SimpleArrayAdapter extends RecyclerView.Adapter<SimpleHolder> {
private final String[] mArray;
public SimpleArrayAdapter(String[] array) {
mArray = array;
}
#Override
public SimpleHolder onCreateViewHolder(ViewGroup parent, int viewType) {
final LayoutInflater inflater = LayoutInflater.from(parent.getContext());
final View view = inflater.inflate(android.R.layout.simple_list_item_1, parent, false);
return new SimpleHolder(view);
}
#Override
public void onBindViewHolder(SimpleHolder holder, int position) {
holder.mTextView.setText(mArray[position]);
}
#Override
public int getItemCount() {
return mArray.length;
}
}
static class SimpleHolder extends RecyclerView.ViewHolder {
private final TextView mTextView;
public SimpleHolder(View itemView) {
super(itemView);
mTextView = (TextView) itemView.findViewById(android.R.id.text1);
}
}
}
Then you have to use the DataBindingUtil methods for inflate the layout.
Inflate inside an Activity:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
DataBindingUtil.setContentView(this, R.layout.content_main);
}
Inflate inside a Fragment:
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
ContentMainBinding bindings = DataBindingUtil.inflate(inflater, R.layout.content_main, container, false);
return bindings.getRoot();
}

No. There is no such directly available attribute in RecyclerView. You have to do it from java code programatically using LayoutManager and RecyclerView.Adapter. Refer this answer.
REASON:
As we know, RecyclerView won't inflate until we set a LayoutManager to it. Also, LayoutManager is necessary to inflate individual item views of RecyclerView. These individual item views are retrieved from the RecyclerView.Adapter. So, until you set both the LayoutManager and RecyclerView.Adapter to RecyclerView, you can't use RecyclerView.
I hope this answer helps you.

I'm afraid this is not possible out of the box, you can extend the RecyclerView and define your own custom attribute which accepts a string array, then you would populate your RecyclerView Adapter with these values.
Check this link:
http://developer.android.com/training/custom-views/create-view.html#customattr

No,In android, Recyclerview doesn't hold android:entries or like attributes.
RecyclerView is successor of listview but still missing entries attribute and onclicklistener
here is android official documentation link
https://developer.android.com/reference/android/support/v7/widget/RecyclerView.html
This site also describes about the android:entries attribute.
http://androidride.com/easiest-way-make-listview-android/

Dynamically load and clear content of LinearLayout

I have the following scenario: I have a LinearLayout on which I then add "cards" to which is a custom class which extends LinearLayout.
The problem is that each card contains an image. Now if I have too many cards to display I get an out of memory error because of the size of the images.
How can I dynamically see which cards are currently displayed on the screen and only load the images of those cards and keep the rest null?
I am struggling to detect which card is currently displayed on the screen and which ones are not. And then also to have an event load and clear images as the user scrolls though the list.

You have to implement a RecyclerView, which does the job for you.
RecyclerView recyclerView = (RecyclerView) view.findViewById(R.id.recycler_view);
recyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
final Adapter adapter = new Adapter();
recyclerView.setAdapter(adapter);
The adapter:
private class Adapter extends RecyclerView.Adapter<MyViewHolder> {
#Override
public MyViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
View view = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.card_main, viewGroup, false);
return new MyViewHolder(view);
}
#Override
public void onBindViewHolder(final MyViewHolder myViewHolder, int i)
// set the content of the card
}
#Override
public int getItemCount() {
return // number of cards
}
}
The ViewHolder
private class MyViewHolder extends RecyclerView.ViewHolder {
public TextView text;
public TextView text2;
public ImageView imageView;
public MyViewHolder(View itemView) {
super(itemView);
text = (TextView) itemView.findViewById(/* your textView */);
text2 = (TextView) itemView.findViewById(/* another textView */);
imageView = (ImageView) itemView.findViewById(/* an image */);
}
}
The Layout:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:design="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivityFragment">
<android.support.v7.widget.RecyclerView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/recycler_view"
/>
</RelativeLayout>

For something like this, you should probably use a Recycler View. This way you can recycle the views and ideally not run into memory issues and not have to have hacky solutions that check what is on the screen and what isn't.