[JAVA] Now, I've summarized the basics of RecyclerView

Constitution

• This time I will make it with the minimum configuration
• RecyclerViewActivity.java ・ ・ ・ Display RecyclerView
• RecyclerViewAdapter.java ・ ・ ・ Associate View with data
• activity_recycler_view.xml ・ ・ ・ Layout of the entire RecyclerView
• row.xml ・ ・ ・ Layout of one row in RecyclerView

procedure

(1) Describe the dependency of Support Library in build.gradle

_ (CardView is also used this time, so describe it) _

build.gradle

dependencies {
	...
    compile 'com.android.support:recyclerview-v7:23.3.0'
    compile 'com.android.support:cardview-v7:23.3.0'
  
    ...
}

(2) Define the layout of the entire RecyclerView

activity_recycler_view.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.RecyclerView xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/recycler_view"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />

(3) Define the layout for each line

row.xml

<?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="64dp"
    android:layout_margin="8dp"
    android:orientation="vertical">

    <TextView
        android:id="@+id/text_view"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_margin="8dp" />
</android.support.v7.widget.CardView>

(4) Describe the initialization process of RecyclerView with Activity

RecyclerViewActivity.java

public class RecyclerViewActivity extends AppCompatActivity {

    private RecyclerView recyclerView;
    private RecyclerViewAdapter recyclerViewAdapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_recycler_view);
        recyclerView = (RecyclerView) findViewById(R.id.recycler_view);

		 // [1] 
        LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this);
        recyclerView.setLayoutManager(linearLayoutManager);

		 // [2] 
        recyclerViewAdapter = new RecyclerViewAdapter(getListData());
        recyclerView.setAdapter(recyclerViewAdapter);
    }

    private List<String> getListData() {
        ArrayList<String> list = new ArrayList<>();
        list.add("January");
        list.add("February");
        list.add("Yayoi");
        list.add("Uzuki");
        list.add("Satsuki");
        list.add("Minazuki");
        list.add("July");
        list.add("Hazuki");
        list.add("Nagatsuki");
        list.add("Kannazuki");
        list.add("Shimotsuki");
        list.add("December");
        return list;
    }

}

(5) Create Adapter class and link data and View

RecyclerViewAdapter.java

public class RecyclerViewAdapter extends RecyclerView.Adapter<RecyclerViewAdapter.ViewHolder> {

    protected List<String> dataSet;

	// [3]
    public static class ViewHolder extends RecyclerView.ViewHolder {
        public final TextView textView;

        public ViewHolder(View v) {
            super(v);
            textView = (TextView) v.findViewById(R.id.text_view);
        }
    }
    
	// [4]
    public RecyclerViewAdapter(List<String> myDataSet) {
        dataSet = myDataSet;
    }

	// [5]
    @Override
    public RecyclerViewAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.row, parent, false);
        ViewHolder vh = new ViewHolder(v);
        return vh;
    }

	// [6]
    @Override
    public void onBindViewHolder(ViewHolder holder, int position) {
        String text = dataSet.get(position);
        holder.textView.setText(text);
    }

	// [7]
    @Override
    public int getItemCount() {
        return dataSet.size();
    }

}

Description