Today we will discuss about CardView in Android SDK which was introduced with the android material design through the support v7 library. We will show you how CardView can be implemented in a RecyclerView list. After reading this article you should feel comfortable creating Lists and Cards view in your android app.
CardView provides a more advanced and flexible way of implementing complex and custom listview with more functionality that is required nowadays for our apps.
We would be creating an Android CardView Example List app, where we will list 7 wonders of Modern World along with a Like Button and a Share Button. On clicking the Like Button it will get highlighted and show a message. Clicking the Share Button will provide you options to share the photo of the Item you clicked. After completion, the app would look like as shown in the video.
Pre-requisites
- Android Studio installed on your PC (Unix or Windows).
- A real time android device (Smartphone or Tablet) configured with Android Studio.
Creating a New Project
- Open Android Studio and create a new project CardViewTutrorial and company domain application.example.com (We have used our own company domain i.e androidtutorialpoint.com. Similarly you can use yours).
- Click Next and choose Min SDK, we have kept the default value. Again Click Next and Choose Blank Activity .
- Choose the Activity as MainActivity and click next.
- Leave all other things as default and Click Finish.
A new project will be created and gradle will resolve all the dependencies.
We would be listing wonders of the world so create a new WonderModel.java class which will have all the field as well getter,setter methods required for a wonder. Add the following code to the class
WonderModel.java
package com.androidtutorialpoint.cardviewtutorial;
public class WonderModel {
String cardName;
int imageResourceId;
int isfav;
int isturned;
public int getIsturned() {
return isturned;
}
public void setIsturned(int isturned) {
this.isturned = isturned;
}
public int getIsfav() {
return isfav;
}
public void setIsfav(int isfav) {
this.isfav = isfav;
}
public String getCardName() {
return cardName;
}
public void setCardName(String cardName) {
this.cardName = cardName;
}
public int getImageResourceId() {
return imageResourceId;
}
public void setImageResourceId(int imageResourceId) {
this.imageResourceId = imageResourceId;
}
}
Adding Support Library for RecyclerView
Add the following code to the App Level build.gradle
compile 'com.android.support:recyclerview-v7:23.1.1'
compile 'com.android.support:cardview-v7:23.1.1'
Now, Gradle will sync your project and add the dependencies.
Add a RecyclerView
- Create a layout file by Right-clicking on the res/layout directory and selecting New → Layout resource file. Name the file fragment_card.xml and click OK to create the file. Open the file add the following code.
fragment_card.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_left_margin"
android:paddingRight="@dimen/activity_right_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context=".MyActivity">
<android.support.v7.widget.RecyclerView
android:id="@+id/cardView"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</RelativeLayout>
Let’s create a layout file. Create a new Layout resource file name it recycle_items.xml and paste the following code.
recycle_items.xml
<android.support.v7.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:card_view="http://schemas.android.com/apk/res-auto"
android:id="@+id/card_view"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="5dp"
card_view:cardCornerRadius="4dp">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="@dimen/card_height"
android:orientation="vertical"
android:weightSum="4">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dip"
android:layout_weight="3.2"
android:orientation="vertical">
<FrameLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_gravity="center_horizontal">
<ImageView
android:id="@+id/coverImageView"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_gravity="center"
android:scaleType="centerCrop"
/>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="left|bottom"
android:background="@android:drawable/screen_background_dark_transparent"
android:orientation="vertical">
<TextView
android:id="@+id/titleTextView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="16dp"
android:textSize="@dimen/text_size"
android:textColor="#FFFFFF"
android:textStyle="bold" />
</LinearLayout>
</FrameLayout>
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dip"
android:layout_weight="0.8"
android:gravity="center|right"
android:orientation="horizontal">
<ImageView
android:id="@+id/likeImageView"
android:layout_width="@dimen/icon_width"
android:layout_height="@dimen/icon_height"
android:padding="@dimen/icon_padding"
android:src="@drawable/ic_like" />
<ImageView
android:id="@+id/shareImageView"
android:layout_width="@dimen/icon_width"
android:layout_height="@dimen/icon_height"
android:padding="@dimen/icon_padding"
android:src="@drawable/ic_share" />
</LinearLayout>
</LinearLayout>
</android.support.v7.widget.CardView>
The layout is pretty much self explanatory, We have used a combination of LinearLayout and FrameLayout‘s to generate a beautiful card layout. We have an ImageView for the android cardview background and a TextView for the displaying the name of the place. Then we have used another LinearLayout for rendering the Like and Share buttons.
Adding The Functionality
- Create a new fragment, name it CardFragment.java and add the following code.
Let’s use arrays to store the name and ImageId for each 7 wonders. We have already added the photos of the places to the drawable folder. You can download the code by clicking on the Download Now Button provided at the top.
CardFragment.java
String Wonders[] = {"Chichen Itza","Christ the Redeemer","Great Wall of China","Machu Picchu","Petra","Taj Mahal","Colosseum"};
int Images[] = {R.drawable.chichen_itza,R.drawable.christ_the_redeemer,R.drawable.great_wall_of_china,R.drawable.machu_picchu,R.drawable.petra,R.drawable.taj_mahal,R.drawable.colosseum};
- In the
onCreate() method we use the initializeList() method to initialize the ArrayList which will be passed to the Adapter later.
@Override
public void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
initializeList();
getActivity().setTitle("7 Wonders of the Modern World");
}
Following is the implementation of the intializeList() method. Add this method after the onCreate() method in the file.
public void initializeList() {
listitems.clear();
for(int i =0;i<7;i++){
WonderModel item = new WonderModel();
item.setCardName(Wonders[i]);
item.setImageResourceId(Images[i]);
item.setIsfav(0);
item.setIsturned(0);
listitems.add(item);
}
}
- A view Holder is required to hold on to the views, so add the following code.
public class MyViewHolder extends RecyclerView.ViewHolder {
public TextView titleTextView;
public ImageView coverImageView;
public ImageView likeImageView;
public ImageView shareImageView;
public MyViewHolder(View v) {
super(v);
titleTextView = (TextView) v.findViewById(R.id.titleTextView);
coverImageView = (ImageView) v.findViewById(R.id.coverImageView);
likeImageView = (ImageView) v.findViewById(R.id.likeImageView);
shareImageView = (ImageView) v.findViewById(R.id.shareImageView);
likeImageView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
int id = (int)likeImageView.getTag();
if( id == R.drawable.ic_like){
likeImageView.setTag(R.drawable.ic_liked);
likeImageView.setImageResource(R.drawable.ic_liked);
Toast.makeText(getActivity(),titleTextView.getText()+" added to favourites",Toast.LENGTH_SHORT).show();
}else{
likeImageView.setTag(R.drawable.ic_like);
likeImageView.setImageResource(R.drawable.ic_like);
Toast.makeText(getActivity(),titleTextView.getText()+" removed from favourites",Toast.LENGTH_SHORT).show();
}
}
});
shareImageView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Uri imageUri = Uri.parse(ContentResolver.SCHEME_ANDROID_RESOURCE +
"://" + getResources().getResourcePackageName(coverImageView.getId())
+ '/' + "drawable" + '/' + getResources().getResourceEntryName((int)coverImageView.getTag()));
Intent shareIntent = new Intent();
shareIntent.setAction(Intent.ACTION_SEND);
shareIntent.putExtra(Intent.EXTRA_STREAM,imageUri);
shareIntent.setType("image/jpeg");
startActivity(Intent.createChooser(shareIntent, getResources().getText(R.string.send_to)));
}
});
}
}
The above code extends the RecyclerView.ViewHolder class and references the ImageView and the TextViews for each view it will be holding.
It also has setOnClickListener() attached to the likeImageView and the shareImageView.
On clicking the like button the state of the button is toggled and it shows a corresponding message that it has added/removed the item to/from favourites.
In the OnClick() for the shareImageView an Intent is fired that shows an option to share the image of the place you have selected.
- Next, extend the
RecyclerView.Adapter class, this adapter is link between the RecyclerView and the data which we want to list. It creates required ViewHolders and also binds the ViewHolder to data from the WonderModel class.
It has three main methods:
onCreateViewHolder() : Inflates the layout and creates a new view Holder.onBindViewHodler() : Binds the data to the view holder.getItemCount() : returns the size of the data to be dispalyed.
Use the following code to create a MyAdapter.
public class MyAdapter extends RecyclerView.Adapter<MyViewHolder> {
private ArrayList<WonderModel> list;
public MyAdapter(ArrayList<WonderModel> Data) {
list = Data;
}
@Override
public MyViewHolder onCreateViewHolder(ViewGroup parent,int viewType) {
View view = LayoutInflater.from(parent.getContext())
.inflate(R.layout.recycle_items, parent, false);
MyViewHolder holder = new MyViewHolder(view);
return holder;
}
@Override
public void onBindViewHolder(final MyViewHolder holder, int position) {
holder.titleTextView.setText(list.get(position).getCardName());
holder.coverImageView.setImageResource(list.get(position).getImageResourceId());
holder.coverImageView.setTag(list.get(position).getImageResourceId());
holder.likeImageView.setTag(R.drawable.ic_like);
}
@Override
public int getItemCount() {
return list.size();
}
}
- In the
onCreateView() method of the CardFragment.java, we reference the RecyclerView that was added in the layout file. We create a new LinearLayoutManager and later set the RecyclerView to use it. The purpose of the LayoutManager is to handle the positioning of the list items and scrolling behaviour.
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_card, container, false);
MyRecyclerView = (RecyclerView) view.findViewById(R.id.cardView);
MyRecyclerView.setHasFixedSize(true);
LinearLayoutManager MyLayoutManager = new LinearLayoutManager(getActivity());
MyLayoutManager.setOrientation(LinearLayoutManager.VERTICAL);
if (listitems.size() > 0 & MyRecyclerView != null) {
MyRecyclerView.setAdapter(new MyAdapter(listitems));
}
MyRecyclerView.setLayoutManager(MyLayoutManager);
return view;
}
Here is the completed CardFragment.java file.
CardFragment.java
package com.androidtutorialpoint.cardviewtutorial;
import android.content.ContentResolver;
import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.Toolbar;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;
import java.util.ArrayList;
public class CardFragment extends Fragment {
ArrayList<WonderModel> listitems = new ArrayList<>();
RecyclerView MyRecyclerView;
String Wonders[] = {"Chichen Itza","Christ the Redeemer","Great Wall of China","Machu Picchu","Petra","Taj Mahal","Colosseum"};
int Images[] = {R.drawable.chichen_itza,R.drawable.christ_the_redeemer,R.drawable.great_wall_of_china,R.drawable.machu_picchu,R.drawable.petra,R.drawable.taj_mahal,R.drawable.colosseum};
@Override
public void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
initializeList();
getActivity().setTitle("7 Wonders of the Modern World");
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_card, container, false);
MyRecyclerView = (RecyclerView) view.findViewById(R.id.cardView);
MyRecyclerView.setHasFixedSize(true);
LinearLayoutManager MyLayoutManager = new LinearLayoutManager(getActivity());
MyLayoutManager.setOrientation(LinearLayoutManager.VERTICAL);
if (listitems.size() > 0 & MyRecyclerView != null) {
MyRecyclerView.setAdapter(new MyAdapter(listitems));
}
MyRecyclerView.setLayoutManager(MyLayoutManager);
return view;
}
@Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
}
public class MyAdapter extends RecyclerView.Adapter<MyViewHolder> {
private ArrayList<WonderModel> list;
public MyAdapter(ArrayList<WonderModel> Data) {
list = Data;
}
@Override
public MyViewHolder onCreateViewHolder(ViewGroup parent,int viewType) {
View view = LayoutInflater.from(parent.getContext())
.inflate(R.layout.recycle_items, parent, false);
MyViewHolder holder = new MyViewHolder(view);
return holder;
}
@Override
public void onBindViewHolder(final MyViewHolder holder, int position) {
holder.titleTextView.setText(list.get(position).getCardName());
holder.coverImageView.setImageResource(list.get(position).getImageResourceId());
holder.coverImageView.setTag(list.get(position).getImageResourceId());
holder.likeImageView.setTag(R.drawable.ic_like);
}
@Override
public int getItemCount() {
return list.size();
}
}
public class MyViewHolder extends RecyclerView.ViewHolder {
public TextView titleTextView;
public ImageView coverImageView;
public ImageView likeImageView;
public ImageView shareImageView;
public MyViewHolder(View v) {
super(v);
titleTextView = (TextView) v.findViewById(R.id.titleTextView);
coverImageView = (ImageView) v.findViewById(R.id.coverImageView);
likeImageView = (ImageView) v.findViewById(R.id.likeImageView);
shareImageView = (ImageView) v.findViewById(R.id.shareImageView);
likeImageView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
int id = (int)likeImageView.getTag();
if( id == R.drawable.ic_like){
likeImageView.setTag(R.drawable.ic_liked);
likeImageView.setImageResource(R.drawable.ic_liked);
Toast.makeText(getActivity(),titleTextView.getText()+" added to favourites",Toast.LENGTH_SHORT).show();
}else{
likeImageView.setTag(R.drawable.ic_like);
likeImageView.setImageResource(R.drawable.ic_like);
Toast.makeText(getActivity(),titleTextView.getText()+" removed from favourites",Toast.LENGTH_SHORT).show();
}
}
});
shareImageView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Uri imageUri = Uri.parse(ContentResolver.SCHEME_ANDROID_RESOURCE +
"://" + getResources().getResourcePackageName(coverImageView.getId())
+ '/' + "drawable" + '/' + getResources().getResourceEntryName((int)coverImageView.getTag()));
Intent shareIntent = new Intent();
shareIntent.setAction(Intent.ACTION_SEND);
shareIntent.putExtra(Intent.EXTRA_STREAM,imageUri);
shareIntent.setType("image/jpeg");
startActivity(Intent.createChooser(shareIntent, getResources().getText(R.string.send_to)));
}
});
}
}
public void initializeList() {
listitems.clear();
for(int i =0;i<7;i++){
WonderModel item = new WonderModel();
item.setCardName(Wonders[i]);
item.setImageResourceId(Images[i]);
item.setIsfav(0);
item.setIsturned(0);
listitems.add(item);
}
}
}
- Next, we will be hosting CardFragment in the
MainActivity. Open MainActivity.java and add the following code.
MainActivity
package com.androidtutorialpoint.cardviewtutorial;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v7.app.AppCompatActivity;
public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
FragmentManager fm = getSupportFragmentManager();
Fragment fragment = fm.findFragmentById(R.id.fragmentContainer);
if (fragment == null) {
fragment = new CardFragment();
;
fm.beginTransaction()
.add(R.id.fragmentContainer, fragment)
.commit();
}
}
}
The layout file for MainActivity i.e. activity_main.xml consists of a FrameLayout as a fragmentContainer.
activity_main.xml
="1.0"="utf-8"
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/fragmentContainer"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
</FrameLayout>
Run the App and you should see a scrollable List of 7 Wonders of the world. Try scrolling through and clicking Like or Share to share the photo. Please comment in case you have any doubts or suggestions.
What’s Next
We hope this tutorial will help you getting started with RecyclerView and CardView on Android. You can reuse the cards to create beautiful apps that have a list interface.
