Thông thường, chúng ta thường sử dụng spinner khi ứng dụng muốn load data từ network. Thay thế cho việc sử dụng spinner, chúng ta có thể loading screen tốt hơn với Facebook’s Shimmer library. Library thêm hiệu ứng Shimmer cho bất cứ custom view mà chúng ta định nghĩa. Bạn có thể chú ý hiệu ứng shimmer ở Facebook trên web và mobile.

1. Facebook’s Shimmer Library

Để tạo hiệu ứng Shimmer trên bất cứ layout, bạn phải đặt layout của banaj bên trong ShimmerFrameLayout. Để bắt animation, bạn phải call startShimmerAnimation() on ShimmerFrameLayout. Ngay lập tức bạn có nhận thấy hiệu ứng Shimmer trên layout của bạn. Bạn có thể tìm kiếm thêm ở Document trên Shimmer’s page.
Ảnh demo
Dưới đây là code để làm được hiệu ứng Shimmer. đầu tiên đặt layout của bạn trong ShimmerFrameLayout

<com.facebook.shimmer.ShimmerFrameLayout
     android:id=“@+id/shimmer_view_container”
     android:layout_width=“wrap_content”
     android:layout_height="wrap_content"
     shimmer:duration="1000">
 
     <View
        android:layout_width="100dp"
        android:layout_height="8dp"
        android:background="#dddddd" />
 
</com.facebook.shimmer.ShimmerFrameLayout>

Để start animation, chúng ta gọi function startShimmerAnimation() từ Activity.

ShimmerFrameLayout shimmerContainer = (ShimmerFrameLayout) findViewById(R.id.shimmer_view_container);
shimmerContainer.startShimmerAnimation();

2. Sample JSON

Để giải thích cho ví dụ demo, tôi sử dụng samplle JSON dưới đây. JSON API

[{
    "id": 1,
    "name": "Salmon Teriyaki",
    "description": "Put the ginger and garlic into a bowl and mix with the soy sauce, maple syrup, mirin and a drizzle of olive oil",
    "price": 140,
    "chef": "Gordon Ramsay",
    "thumbnail": "https://api.androidhive.info/images/food/1.jpg",
    "timestamp": "2 min ago"
}, {
    "id": 2,
    "name": "Grilled Mushroom",
    "description": "Combine butter, dill and garlic salt, brush over mushrooms.",
    "price": 150,
    "chef": "Ravi Tamada",
    "thumbnail": "https://api.androidhive.info/images/food/2.jpg",
    "timestamp": "5 min ago"
}]

3. Create New Project

  1. Tạo 1 project từ Android Studio: File -> New Project -> Basic Activity từ template
  2. Thêm thư viện Shimmer từ dependency từ build.grade và rebuild
build.gradle
dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'com.android.support:appcompat-v7:26.1.0'
 
    // Shimmer
    implementation 'com.facebook.shimmer:shimmer:0.1.0@aar'
}
  1. Thêm đoạn code dưới vào file colors và dimens
colors.xml
<!--?xml version="1.0" encoding="utf-8"?-->
<resources>
    <color name="colorPrimary">#d91248</color>
    <color name="colorPrimaryDark">#d91248</color>
    <color name="colorAccent">#3ad23e</color>
    <color name="placeholder_bg">#dddddd</color>
    <color name="item_name">#0c0c0c</color>
    <color name="description">#1a1a1a</color>
    <color name="chef">#777</color>
    <color name="timestamp">#777</color>
</resources>
dimens.xml
<!--?xml version="1.0" encoding="utf-8"?-->
<resources>
    <dimen name="activity_padding">16dp</dimen>
    <dimen name="placeholder_image">50dp</dimen>
    <dimen name="placeholder_text_height">8dp</dimen>
    <dimen name="activity_padding_horizontal">16dp</dimen>
    <dimen name="padding_10">10dp</dimen>
    <dimen name="name">15dp</dimen>
    <dimen name="chef">12dp</dimen>
    <dimen name="timestamp">11dp</dimen>
    <dimen name="description">15dp</dimen>
    <dimen name="price">13dp</dimen>
</resources>
  1. Tạo layout mới với tên recipe_placeholder_item.xml. Trong file chúng ta định nghĩa cách hiển thị layout
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:padding="@dimen/activity_padding">
 
    <View
        android:id="@+id/thumbnail"
        android:layout_width="@dimen/placeholder_image"
        android:layout_height="@dimen/placeholder_image"
        android:layout_marginRight="@dimen/activity_padding"
        android:background="@color/placeholder_bg" />
 
    <View
        android:id="@+id/name"
        android:layout_width="150dp"
        android:layout_height="10dp"
        android:layout_marginBottom="10dp"
        android:layout_toRightOf="@id/thumbnail"
        android:background="@color/placeholder_bg" />
 
    <View
        android:layout_width="100dp"
        android:layout_height="@dimen/placeholder_text_height"
        android:layout_below="@id/name"
        android:layout_toRightOf="@id/thumbnail"
        android:background="@color/placeholder_bg" />
 
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_below="@id/thumbnail"
        android:layout_marginBottom="40dp"
        android:layout_marginTop="20dp"
        android:orientation="vertical">
 
        <View
            android:layout_width="match_parent"
            android:layout_height="@dimen/placeholder_text_height"
            android:layout_marginRight="100dp"
            android:background="@color/placeholder_bg" />
 
        <View
            android:layout_width="match_parent"
            android:layout_height="@dimen/placeholder_text_height"
            android:layout_marginRight="50dp"
            android:layout_marginTop="10dp"
            android:background="@color/placeholder_bg" />
 
        <View
            android:layout_width="match_parent"
            android:layout_height="@dimen/placeholder_text_height"
            android:layout_marginRight="160dp"
            android:layout_marginTop="10dp"
            android:background="@color/placeholder_bg" />
 
    </LinearLayout>
 
</RelativeLayout>
  1. Tiếp tục, chúng ta đặt layout đã tạo ở trên vào activity_main.xml.
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:shimmer="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:background="@android:color/white"
    tools:context="info.androidhive.shimmer.MainActivity">
 
    <com.facebook.shimmer.ShimmerFrameLayout
        android:id="@+id/shimmer_view_container"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:orientation="vertical"
        shimmer:duration="800">
 
        <!-- Adding 3 rows of placeholders -->
        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:orientation="vertical">
 
            <include layout="@layout/recipe_placeholder_item" />
 
            <include layout="@layout/recipe_placeholder_item" />
 
            <include layout="@layout/recipe_placeholder_item" />
 
        </LinearLayout>
 
    </com.facebook.shimmer.ShimmerFrameLayout>
 
</android.support.constraint.ConstraintLayout>
  1. Trong MainActivity.java gọi function startShimmerAnimation() trong onResume(). Và pausing animation trong onPause().
MainActivity.java
import com.facebook.shimmer.ShimmerFrameLayout;
 
public class MainActivity extends AppCompatActivity {
 
    private ShimmerFrameLayout mShimmerViewContainer;
 
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
 
        mShimmerViewContainer = findViewById(R.id.shimmer_view_container);
    }
 
    @Override
    public void onResume() {
        super.onResume();
        mShimmerViewContainer.startShimmerAnimation();
    }
 
    @Override
    public void onPause() {
        mShimmerViewContainer.stopShimmerAnimation();
        super.onPause();
    }
}

Ngây bây giờ nếu chạy ứng dụng, bạn có thể thấy Shimmer animation bên dưới
Ảnh demo

3.1 Loading data từ JSON và hiding đến Shimmer

  1. Trong file build.gradle and add RecyclerView, Glide and Volley dependencies.
build.gradle
dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'com.android.support:appcompat-v7:26.1.0'
    // ...
 
    // Shimmer
    implementation 'com.facebook.shimmer:shimmer:0.1.0@aar'
 
    // RecyclerView
    implementation 'com.android.support:recyclerview-v7:26.1.0'
 
    // glide image library
    implementation 'com.github.bumptech.glide:glide:3.7.0'
 
    // volley http library
    implementation 'com.android.volley:volley:1.0.0'
    implementation 'com.google.code.gson:gson:2.6.2'
}
  1. Tạo file MyApplication.java và extend từ Application. Class này là singleton dùng để khởi tạo Volley.
MyApplication.java
package info.androidhive.shimmer;
 
/**
 * Created by ravi on 18/01/18.
 */
 
import android.app.Application;
import android.text.TextUtils;
 
import com.android.volley.Request;
import com.android.volley.RequestQueue;
import com.android.volley.toolbox.Volley;
 
public class MyApplication extends Application {
 
    public static final String TAG = MyApplication.class
            .getSimpleName();
 
    private RequestQueue mRequestQueue;
 
    private static MyApplication mInstance;
 
    @Override
    public void onCreate() {
        super.onCreate();
        mInstance = this;
    }
 
    public static synchronized MyApplication getInstance() {
        return mInstance;
    }
 
    public RequestQueue getRequestQueue() {
        if (mRequestQueue == null) {
            mRequestQueue = Volley.newRequestQueue(getApplicationContext());
        }
 
        return mRequestQueue;
    }
 
    public <T> void addToRequestQueue(Request<T> req, String tag) {
        // set the default tag if tag is empty
        req.setTag(TextUtils.isEmpty(tag) ? TAG : tag);
        getRequestQueue().add(req);
    }
 
    public <T> void addToRequestQueue(Request<T> req) {
        req.setTag(TAG);
        getRequestQueue().add(req);
    }
 
    public void cancelPendingRequests(Object tag) {
        if (mRequestQueue != null) {
            mRequestQueue.cancelAll(tag);
        }
    }
}
  1. Đăng ký MyApplication trong AndroidManifest.xml
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="info.androidhive.shimmer">
 
    <uses-permission android:name="android.permission.INTERNET"/>
 
    <!-- add .MyApplication class -->
    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:name=".MyApplication"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
 
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>
 
</manifest> 
  1. Open activity_main.xml và thêm RecyclerView dưới layout ShimmerFrameLayout.
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:shimmer="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:background="@android:color/white"
    tools:context="info.androidhive.shimmer.MainActivity">
 
    <com.facebook.shimmer.ShimmerFrameLayout
        android:id="@+id/shimmer_view_container"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:orientation="vertical"
        shimmer:duration="800">
 
        <!-- Adding 3 rows of placeholders -->
        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:orientation="vertical">
 
            <include layout="@layout/layout_placeholder_row" />
 
            <include layout="@layout/layout_placeholder_row" />
 
            <include layout="@layout/layout_placeholder_row" />
 
        </LinearLayout>
 
    </com.facebook.shimmer.ShimmerFrameLayout>
 
    <android.support.v7.widget.RecyclerView
        android:id="@+id/recycler_view"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:scrollbars="vertical" />
 
</android.support.constraint.ConstraintLayout>
  1. Tạo class Recipe.java và định nghĩa các biến cần dùng đê parse JSON .
Recipe.java
package info.androidhive.shimmer;

/**
* Created by ravi on 18/01/18.
*/

public class Recipe {
   int id;
   String name;
   String description;
   double price;
   String thumbnail;
   String chef;
   String timestamp;

   public Recipe() {
   }

   public int getId() {
       return id;
   }

   public String getName() {
       return name;
   }

   public String getDescription() {
       return description;
   }

   public double getPrice() {
       return price;
   }

   public String getThumbnail() {
       return thumbnail;
   }

   public String getChef() {
       return chef;
   }

   public String getTimestamp() {
       return timestamp;
   }
}
  1. Tạo layout recipe_list_item.xml. Layout này sẽ hiển thị chính xác item cần hiển thị gồm: image và TextViews.
recipe_list_item.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="@android:color/white"
    android:clickable="true"
    android:foreground="?attr/selectableItemBackground"
    android:padding="@dimen/activity_padding_horizontal">
 
    <ImageView
        android:id="@+id/thumbnail"
        android:layout_width="@dimen/placeholder_image"
        android:layout_height="@dimen/placeholder_image"
        android:layout_marginRight="@dimen/padding_10"
        android:scaleType="centerCrop" />
 
    <TextView
        android:id="@+id/name"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_toRightOf="@id/thumbnail"
        android:ellipsize="end"
        android:fontFamily="sans-serif-medium"
        android:maxLines="1"
        android:textColor="@color/item_name"
        android:textSize="@dimen/name" />
 
    <TextView
        android:id="@+id/chef"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@id/name"
        android:layout_toRightOf="@id/thumbnail"
        android:maxLines="1"
        android:textColor="@color/chef"
        android:textSize="@dimen/chef" />
 
    <TextView
        android:id="@+id/timestamp"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@id/chef"
        android:layout_toRightOf="@id/thumbnail"
        android:maxLines="1"
        android:text="2 min ago"
        android:textColor="@color/timestamp"
        android:textSize="@dimen/timestamp" />
 
    <TextView
        android:id="@+id/description"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@id/thumbnail"
        android:layout_marginTop="@dimen/activity_padding_horizontal"
        android:ellipsize="end"
        android:maxLines="3"
        android:textColor="@color/description"
        android:textSize="@dimen/description" />
 
    <TextView
        android:id="@+id/price"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@id/description"
        android:layout_marginTop="@dimen/padding_10"
        android:textColor="@color/colorPrimary"
        android:textSize="@dimen/price"
        android:textStyle="bold" />
 
</RelativeLayout>
  1. Tạo Adapter RecipeListAdapter.java cho RecyclerView.
package info.androidhive.shimmer;
 
/**
 * Created by ravi on 18/01/18.
 */
 
import android.content.Context;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.TextView;
 
import com.bumptech.glide.Glide;
 
import java.util.List;
 
public class RecipeListAdapter extends RecyclerView.Adapter<RecipeListAdapter.MyViewHolder> {
    private Context context;
    private List<Recipe> cartList;
 
    public class MyViewHolder extends RecyclerView.ViewHolder {
        public TextView name, description, price, chef, timestamp;
        public ImageView thumbnail;
 
        public MyViewHolder(View view) {
            super(view);
            name = view.findViewById(R.id.name);
            chef = view.findViewById(R.id.chef);
            description = view.findViewById(R.id.description);
            price = view.findViewById(R.id.price);
            thumbnail = view.findViewById(R.id.thumbnail);
            timestamp = view.findViewById(R.id.timestamp);
        }
    }
 
 
    public RecipeListAdapter(Context context, List<Recipe> cartList) {
        this.context = context;
        this.cartList = cartList;
    }
 
    @Override
    public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View itemView = LayoutInflater.from(parent.getContext())
                .inflate(R.layout.recipe_list_item, parent, false);
 
        return new MyViewHolder(itemView);
    }
 
    @Override
    public void onBindViewHolder(MyViewHolder holder, final int position) {
        final Recipe recipe = cartList.get(position);
        holder.name.setText(recipe.getName());
        holder.chef.setText("By " + recipe.getChef());
        holder.description.setText(recipe.getDescription());
        holder.price.setText("Price: ₹" + recipe.getPrice());
        holder.timestamp.setText(recipe.getTimestamp());
 
        Glide.with(context)
                .load(recipe.getThumbnail())
                .into(holder.thumbnail);
    }
    // recipe
    @Override
    public int getItemCount() {
        return cartList.size();
    }
}
  1. Open MainActivity.java và thay đổi code như bên dưới.

fetchRecipes() method fetches JSON bằng Volley’s http. Sử dụng GSon để parse JSON.
JSON được parse và add RecyclerView adapter, List item sẽ được rendered vàShimmerFrameLayout sẽ bị ẩn đi.

MainActivity.java
package info.androidhive.shimmer;
 
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.DefaultItemAnimator;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.util.Log;
import android.view.View;
import android.widget.Toast;
 
import com.android.volley.Response;
import com.android.volley.VolleyError;
import com.android.volley.toolbox.JsonArrayRequest;
import com.facebook.shimmer.ShimmerFrameLayout;
import com.google.gson.Gson;
import com.google.gson.reflect.TypeToken;
 
import org.json.JSONArray;
 
import java.util.ArrayList;
import java.util.List;
 
public class MainActivity extends AppCompatActivity {
 
    private static final String TAG = MainActivity.class.getSimpleName();
    private RecyclerView recyclerView;
    private List<Recipe> cartList;
    private RecipeListAdapter mAdapter;
 
    private ShimmerFrameLayout mShimmerViewContainer;
 
    // URL to fetch menu json
    // this endpoint takes 2 sec before giving the response to add
    // some delay to test the Shimmer effect
    private static final String URL = "https://api.androidhive.info/json/shimmer/menu.php";
 
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
 
        mShimmerViewContainer = findViewById(R.id.shimmer_view_container);
 
        recyclerView = findViewById(R.id.recycler_view);
        cartList = new ArrayList<>();
        mAdapter = new RecipeListAdapter(this, cartList);
 
        RecyclerView.LayoutManager mLayoutManager = new LinearLayoutManager(getApplicationContext());
        recyclerView.setLayoutManager(mLayoutManager);
        recyclerView.setItemAnimator(new DefaultItemAnimator());
        recyclerView.addItemDecoration(new MyDividerItemDecoration(this, LinearLayoutManager.VERTICAL, 16));
        recyclerView.setAdapter(mAdapter);
 
        // making http call and fetching menu json
        fetchRecipes();
    }
 
    /**
     * method make volley network call and parses json
     */
    private void fetchRecipes() {
        JsonArrayRequest request = new JsonArrayRequest(URL,
                new Response.Listener<JSONArray>() {
                    @Override
                    public void onResponse(JSONArray response) {
                        if (response == null) {
                            Toast.makeText(getApplicationContext(), "Couldn't fetch the menu! Pleas try again.", Toast.LENGTH_LONG).show();
                            return;
                        }
 
                        List<Recipe> recipes = new Gson().fromJson(response.toString(), new TypeToken<List<Recipe>>() {
                        }.getType());
 
                        // adding recipes to cart list
                        cartList.clear();
                        cartList.addAll(recipes);
 
                        // refreshing recycler view
                        mAdapter.notifyDataSetChanged();
 
                        // stop animating Shimmer and hide the layout
                        mShimmerViewContainer.stopShimmerAnimation();
                        mShimmerViewContainer.setVisibility(View.GONE);
                    }
                }, new Response.ErrorListener() {
            @Override
            public void onErrorResponse(VolleyError error) {
                // error in getting json
                Log.e(TAG, "Error: " + error.getMessage());
                Toast.makeText(getApplicationContext(), "Error: " + error.getMessage(), Toast.LENGTH_SHORT).show();
            }
        });
 
        MyApplication.getInstance().addToRequestQueue(request);
    }
 
    @Override
    public void onResume() {
        super.onResume();
        mShimmerViewContainer.startShimmerAnimation();
    }
 
    @Override
    public void onPause() {
        mShimmerViewContainer.stopShimmerAnimation();
        super.onPause();
    }
}

Video Demo

Source Code