[JAVA] Implementierung von vertikalem und horizontalem Scrollen, wie es in letzter Zeit häufig bei Android zu sehen ist

Hallo. Das ist m_saeki.

Gibt es viele aktuelle Apps, die vertikal und horizontal scrollen? Ich habe ein Beispiel implementiert, bitte beziehen Sie sich darauf! https://github.com/m-saeki0926/android_demo_recyclerview Leider ist es Java, nicht Kotlin. .. ..

Überblick

Definieren Sie VerticalRecyclerView in MainActivity HorizontalAdapter ist in VerticalAdapte definiert.

Es hat eine verschachtelte Struktur, wie in der folgenden Abbildung gezeigt. Es gibt andere Implementierungsmethoden, es ist also nur ein Beispiel ^^

Main

MainActivity.java

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        initRecyclerView();
    }

    private void initRecyclerView() {
        // Setting recycler view
        RecyclerView recyclerView = findViewById(R.id.recycler_view);
        recyclerView.setLayoutManager(new LinearLayoutManager(this));
        // Generate demo data
        List<Object> demoList = new ArrayList<>();
        demoList.add(null);
        demoList.add(null);
        demoList.add(null);
        demoList.add(null);
        demoList.add(null);
        // Setting adapter
        VerticalAdapter adapter = new VerticalAdapter(this, demoList);
        recyclerView.swapAdapter(adapter, false);
    }
}

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout 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/recycler_view"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"/>

</android.support.constraint.ConstraintLayout>

Adapter

VerticalAdapter.java

public class VerticalAdapter extends RecyclerView.Adapter {

    private Context context;
    private List<Object> list;

    public VerticalAdapter(@NonNull final Context context, @NonNull final List<Object> list) {
        this.context = context;
        this.list = list;
    }

    @Override
    public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View defaultView = LayoutInflater.from(parent.getContext()).inflate(R.layout.list_item_vertical, parent, false);
        return new ContentViewHolder(defaultView);
    }

    @Override
    public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
        ((ContentViewHolder) holder).setData(list.get(position), context);
    }

    @Override
    public int getItemCount() {
        return list.size();
    }

    static class ContentViewHolder extends RecyclerView.ViewHolder {

        View view;

        ContentViewHolder(View itemView) {
            super(itemView);
            this.view = itemView;
        }

        void setData(Object item, Context context) {
            // Setting recycler view
            RecyclerView recyclerView = view.findViewById(R.id.horizontal_recycler_view);
            recyclerView.setLayoutManager(new LinearLayoutManager(context, LinearLayoutManager.HORIZONTAL, false));
            // Generate demo data
            List<Object> demoList = new ArrayList<>();
            demoList.add(null);
            demoList.add(null);
            demoList.add(null);
            demoList.add(null);
            demoList.add(null);
            // Setting adapter
            HorizontalAdapter adapter = new HorizontalAdapter(context, demoList);
            recyclerView.swapAdapter(adapter, false);
        }
    }
}

list_item_vertical.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical">

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="#000"
        android:gravity="right"
        android:padding="10dp"
        android:text="View All"
        android:textColor="#FFF" />

    <android.support.v7.widget.RecyclerView
        android:id="@+id/horizontal_recycler_view"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"/>

</LinearLayout>

HorizontalAdapter.java

public class HorizontalAdapter extends RecyclerView.Adapter {

    private Context context;
    private List<Object> list;

    public HorizontalAdapter(@NonNull final Context context, @NonNull final List<Object> list) {
        this.context = context;
        this.list = list;
    }

    @Override
    public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View defaultView = LayoutInflater.from(parent.getContext()).inflate(R.layout.list_item_horizontal, parent, false);
        return new HorizontalAdapter.ContentViewHolder(defaultView);
    }

    @Override
    public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
        ((HorizontalAdapter.ContentViewHolder) holder).setData(list.get(position), context);
    }

    @Override
    public int getItemCount() {
        return list.size();
    }

    static class ContentViewHolder extends RecyclerView.ViewHolder {

        View view;

        ContentViewHolder(View itemView) {
            super(itemView);
            this.view = itemView;
        }

        void setData(Object item, Context context) {
          //Verarbeitung implementieren
        }
    }
}

list_item_horizontal.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="240dp"
    android:layout_height="wrap_content">

    <ImageView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:adjustViewBounds="true"
        android:scaleType="centerCrop"
        android:src="@drawable/sample" />

</RelativeLayout>