Going to show you to make header with items in a Recycler view.
Step 1- Add dependency into your gradle file.
compile 'com.android.support:recyclerview-v7:23.2.0' // CardView compile 'com.android.support:cardview-v7:23.2.0'
Cardview is used for decoration purpose.
Step2- Make three xml files. One for main activity.Second for Header layout.Third for list item layout.
activity_main.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.support.v7.widget.RecyclerView android:id="@+id/my_recycler_view" android:scrollbars="vertical" android:layout_width="match_parent" android:layout_height="match_parent"> </android.support.v7.widget.RecyclerView> </RelativeLayout>
header.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="wrap_content" xmlns:app="http://schemas.android.com/apk/res-auto"> <android.support.v7.widget.CardView android:layout_width="match_parent" android:layout_height="wrap_content" app:cardElevation="2dp"> <TextView android:id="@+id/txtHeader" android:gravity="center" android:textColor="#000000" android:textSize="@dimen/abc_text_size_large_material" android:background="#DCDCDC" android:layout_width="match_parent" android:layout_height="50dp" /> </android.support.v7.widget.CardView> </LinearLayout>
list.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:card_view="http://schemas.android.com/apk/res-auto" xmlns:app="http://schemas.android.com/tools" android:orientation="vertical" android:layout_width="match_parent" android:layout_height="wrap_content"> <LinearLayout android:layout_width="match_parent" android:layout_height="wrap_content" android:orientation="vertical"> <android.support.v7.widget.CardView android:layout_width="match_parent" android:layout_height="wrap_content" app:cardElevation="1dp"> <TextView android:id="@+id/txtName" android:text="abc" android:layout_width="match_parent" android:layout_height="wrap_content" /> </android.support.v7.widget.CardView> </LinearLayout> </LinearLayout>
Step 3- Create three bean classes.
Header.java
public class Header extends ListItem { private String header; public Header(){} public String getHeader() { return header; } public void setHeader(String header) { this.header = header; } }
ContentItem.java
public class ContentItem extends ListItem { private String name; private String rollnumber; @Override public String getName() { return name; } @Override public void setName(String name) { this.name = name; } public String getRollnumber() { return rollnumber; } public void setRollnumber(String rollnumber) { this.rollnumber = rollnumber; } }
ListItem.java
public class ListItem { private String name; public ListItem(){} public String getName() { return name; } public void setName(String name) { this.name = name; } private int id; public int getId() { return id; } public void setId(int id) { this.id = id; } }
Step 4- Create an adapter named MyRecyclerAdapter.java
public class MyRecyclerAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder>{ private static final int TYPE_HEADER = 0; private static final int TYPE_ITEM = 1; //Header header; List<ListItem> list; public MyRecyclerAdapter(List<ListItem> headerItems) { this.list = headerItems; } @Override public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) { if(viewType==TYPE_HEADER) { View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.header, parent, false); return new VHHeader(v); } else { View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.list, parent, false); return new VHItem(v); } // return null; } @Override public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) { if(holder instanceof VHHeader) { // VHHeader VHheader = (VHHeader)holder; Header currentItem = (Header) list.get(position); VHHeader VHheader = (VHHeader)holder; VHheader.txtTitle.setText(currentItem.getHeader()); } else if(holder instanceof VHItem) { ContentItem currentItem = (ContentItem) list.get(position); VHItem VHitem = (VHItem)holder; VHitem.txtName.setText(currentItem.getName()); } } public int getItemViewType(int position) { if(isPositionHeader(position)) return TYPE_HEADER; return TYPE_ITEM; } private boolean isPositionHeader(int position) { return list.get(position) instanceof Header; } @Override public int getItemCount() { return list.size(); } class VHHeader extends RecyclerView.ViewHolder{ TextView txtTitle; public VHHeader(View itemView) { super(itemView); this.txtTitle = (TextView)itemView.findViewById(R.id.txtHeader); } } class VHItem extends RecyclerView.ViewHolder{ TextView txtName; public VHItem(View itemView) { super(itemView); this.txtName = (TextView)itemView.findViewById(R.id.txtName); } } }
Step 5- In MainActivity add the following code:
public class MainActivity extends AppCompatActivity { RecyclerView recyclerView; List<List<ListItem>> arraylist; MyRecyclerAdapter adapter; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); recyclerView = (RecyclerView)findViewById(R.id.my_recycler_view); LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this); adapter = new MyRecyclerAdapter(getList()); recyclerView.setLayoutManager(linearLayoutManager); recyclerView.setAdapter(adapter); } private ArrayList<ListItem> getList() { ArrayList<ListItem> arrayList=new ArrayList<>(); for(int j=0;j<=4;j++) { Header header=new Header(); header.setHeader("header"+j); arrayList.add(header); for (int i = 0; i <= 3; i++) { ContentItem item = new ContentItem(); item.setRollnumber(i + ""); item.setName("A" + i); arrayList.add(item); } } return arrayList; } }
The function getList() is dynamically generating the data for the headers and for list items.
