CardView doesn't show on my RecycleView when pushing data from PHP/MySQL locally

Question

I'm a beginner in Android Studio. My aim is to load my data from Wamp server using PHP with MySQL into recyclerView using CardView. But everything runs fine. But I'm not getting the output when I run my apps.

My dependency is this, please ignore Firebase one

 compile 'com.facebook.android:facebook-android-sdk:[4,5)'
compile 'com.android.support:appcompat-v7:25.3.1'
compile 'com.android.support:support-v4:25.3.1'
compile 'com.android.support:cardview-v7:25.3.1'
compile 'com.android.support:recyclerview-v7:25.3.1'

compile 'com.google.firebase:firebase-core:10.2.4'
compile 'com.google.firebase:firebase-auth:10.2.4'
compile 'com.google.android.gms:play-services-auth:10.2.4'
compile 'com.android.support:design:25.3.1'
compile 'com.google.firebase:firebase-database:10.2.4'
compile 'com.squareup.okhttp3:okhttp:3.6.0'
compile 'com.mcxiaoke.volley:library-aar:1.0.0'
testCompile 'junit:junit:4.12'

Main2Activity class

 public class Main2Activity extends AppCompatActivity {

ProgressDialog progressDialog;
List<companyCardDetailsClass> rowListItem;
private RecyclerView recyclerView;
private GridLayoutManager gridLayoutManager;
private CompanyCardRecycleViewAdapterClass adapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main2);
    Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);

    FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
    fab.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
                    .setAction("Action", null).show();
        }
    });
    getSupportActionBar().setDisplayHomeAsUpEnabled(true);
    rowListItem = new ArrayList<>();
    recyclerView = (RecyclerView)findViewById(R.id.recycler_view1) ;

    gridLayoutManager = new GridLayoutManager(this,1);
    recyclerView.setLayoutManager(gridLayoutManager);
    recyclerView.setHasFixedSize(true);

    adapter = new CompanyCardRecycleViewAdapterClass(this, rowListItem);
    recyclerView.setAdapter(adapter);
    load_data_from_server(0);
}

private void load_data_from_server(int id) {
    AsyncTask<Integer,Void,Void> task = new AsyncTask<Integer, Void, Void>() {
        @Override
        protected Void doInBackground(Integer... integers) {
            //send request to server for data
            OkHttpClient client = new OkHttpClient();
            Request request = new Request.Builder().url("http://192.168.161.2/stamploaddatabase/getMerchantDetails.php").build();
            try {
                //get response from server in form of JSon array
                Response response = client.newCall(request).execute();
                JSONArray array = new JSONArray(response.body().string());
                for (int i = 0; i < array.length(); i++) {
                    JSONObject object = array.getJSONObject(i);
                    companyCardDetailsClass data = new companyCardDetailsClass(object.getInt("user_id"), object.getString("companyname"), object.getString("location"),
                            object.getInt("logo"));
                    rowListItem.add(data);

                }

            } catch (JSONException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }

            return null;
        }

        @Override
        protected void onPostExecute(Void aVoid) {
            adapter.notifyDataSetChanged();
        }
    };
    task.execute(id);
}




<android.support.v7.widget.CardView
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app2="http://schemas.android.com/apk/res-auto"
xmlns:card_view="http://schemas.android.com/tools"
android:id="@+id/card_view"
android:layout_width="match_parent"
android:layout_height="300dp"
android:layout_margin="5dp"
card_view:cardCornerRadius="4dp"
card_view:contentPadding="10dp">



    <LinearLayout
        android:orientation="horizontal"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
       >

        <ImageView
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:id="@+id/image_company"
            android:layout_gravity="center_horizontal"
            android:scaleType="centerCrop"
            android:layout_weight="0.25"
            />


</LinearLayout>

        <LinearLayout
            android:orientation="horizontal"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:paddingLeft="8px">

            <TextView
                android:text="Text"
                android:layout_width="0dp"
                android:layout_height="wrap_content"
                android:id="@+id/name_company"
                card_view:textSize="14sp"
                android:layout_weight="2.37"
                android:textColor="@android:color/holo_red_light" />

            <TextView
                android:text="TextView"
                android:layout_width="0dp"
                android:layout_height="wrap_content"
                android:id="@+id/address_company"
                card_view:textSize="12sp"
                android:layout_weight="0.22"
                android:layout_below="@+id/name_company"/>
        </LinearLayout>

    <LinearLayout

        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:id="@+id/linear_layout2"
        card_view:orientation="horizontal"
        android:layout_gravity="right"
        android:orientation="horizontal"
       >

        <Button
            android:text="Redeem"
            android:layout_width="112dp"
            android:layout_height="32dp"
            android:id="@+id/btn_redeem1"
            android:paddingRight="20dp"
            card_view:text="Redeem"
            android:layout_weight="0.25"
            android:background="@drawable/shape"/>
         card_view:background="@color/btn_redeem"/>

        <ImageView
            android:layout_width="51dp"
            android:layout_height="35dp"
            android:src="@drawable/ic_like"
            android:id="@+id/like"
            />
        <ImageView
            android:layout_width="51dp"
            android:layout_height="35dp"
            android:src="@drawable/ic_share"
            android:id="@+id/share"
             />


    </LinearLayout>

Adapter and Holder

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

 List<companyCardDetailsClass> itemList;
 private Context context;

public CompanyCardRecycleViewAdapterClass(Context context, List<companyCardDetailsClass> itemList ) {
    super();
    this.itemList = itemList;
    this.context = context;


}

@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
    View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.company_card_list, parent, false);
    ViewHolder holder = new ViewHolder(view);
    return holder;

}

@Override
public void onBindViewHolder(ViewHolder holder, int position) {
    holder.CompanyName.setText(itemList.get(position).getCompanyname());
    holder.CompanyAddress.setText(itemList.get(position).getLocation());
    holder.CompanyProfilePhoto.setImageResource(itemList.get(position).getImageCpny());

}

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

public class ViewHolder extends RecyclerView.ViewHolder {
    public TextView CompanyName;
    public TextView CompanyAddress;
    public ImageView CompanyProfilePhoto;
    public ImageView likeImage;
    public ImageView shareImage;
    public Button RedeemBtn;
    public ViewHolder(View view) {
        super(view);
        CompanyAddress =(TextView)itemView.findViewById(R.id.address_company);
        CompanyName = (TextView)itemView.findViewById(R.id.name_company);
        CompanyProfilePhoto = (ImageView)itemView.findViewById(R.id.image_company);
        likeImage = (ImageView)itemView.findViewById(R.id.like);
        shareImage = (ImageView)itemView.findViewById(R.id.share);
        RedeemBtn = (Button)itemView.findViewById(R.id.btn_redeem1);
        final RecyclerView recyclerView = (RecyclerView)itemView.findViewById(R.id.recycler_view1);
    }
}
}

**My Java class data **

public class companyCardDetailsClass {
private int id_company;
private String companyname;


private String location;
private int ImageCpny;

public companyCardDetailsClass() {
}

public companyCardDetailsClass(int id_company, String companyname, String location, int imageCpny) {
    this.id_company = id_company;
    this.companyname = companyname;
    ImageCpny = imageCpny;
    this.location = location;
}

public String getLocation() {
    return location;
}

public void setLocation(String location) {
    this.location = location;
}

public int getIdCompany(){return id_company;}
public void setId_company(int id_company){this.id_company = id_company;}

public String getCompanyname (){
    return companyname;
}
public void setCompanyname (String companyname){
    this.companyname = companyname;
}



public int getImageCpny(){
    return ImageCpny;
 }
public void setImageCpny(int ImageCpny){
    this.ImageCpny = ImageCpny;

  }
  }

then my layout activity Layout with recyclerView

<?xml version="1.0" encoding="utf-8"?>
   <RelativeLayout
  xmlns:android="http://schemas.android.com/apk/res/android"
  xmlns:app="http://schemas.android.com/apk/res-auto"
  xmlns:tools="http://schemas.android.com/tools"
  android:id="@+id/content_main2"
  android:layout_width="match_parent"
  android:layout_height="wrap_content"
  xmlns:card_view="http://schemas.android.com/tools"
  app:layout_behavior="@string/appbar_scrolling_view_behavior"
   tools:context="com.example.drake.stamploadproject.Main2Activity"
  tools:showIn="@layout/activity_main2">
  <android.support.v7.widget.RecyclerView
    android:id = "@+id/recycler_view1"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"

    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    android:layout_marginTop="5dp">
</android.support.v7.widget.RecyclerView>

cardView Layout

<android.support.v7.widget.CardView
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app2="http://schemas.android.com/apk/res-auto"
xmlns:card_view="http://schemas.android.com/tools"
android:id="@+id/card_view"
android:layout_width="match_parent"
android:layout_height="300dp"
android:layout_margin="5dp"
card_view:cardCornerRadius="4dp"
card_view:contentPadding="10dp">



    <LinearLayout
        android:orientation="horizontal"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
       >

        <ImageView
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:id="@+id/image_company"
            android:layout_gravity="center_horizontal"
            android:scaleType="centerCrop"
            android:layout_weight="0.25"
            />


</LinearLayout>

        <LinearLayout
            android:orientation="horizontal"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:paddingLeft="8px">

            <TextView
                android:text="Text"
                android:layout_width="0dp"
                android:layout_height="wrap_content"
                android:id="@+id/name_company"
                card_view:textSize="14sp"
                android:layout_weight="2.37"
                android:textColor="@android:color/holo_red_light" />

            <TextView
                android:text="TextView"
                android:layout_width="0dp"
                android:layout_height="wrap_content"
                android:id="@+id/address_company"
                card_view:textSize="12sp"
                android:layout_weight="0.22"
                android:layout_below="@+id/name_company"/>
        </LinearLayout>

    <LinearLayout

        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:id="@+id/linear_layout2"
        card_view:orientation="horizontal"
        android:layout_gravity="right"
        android:orientation="horizontal"
       >

        <Button
            android:text="Redeem"
            android:layout_width="112dp"
            android:layout_height="32dp"
            android:id="@+id/btn_redeem1"
            android:paddingRight="20dp"
            card_view:text="Redeem"
            android:layout_weight="0.25"
            android:background="@drawable/shape"/>
         card_view:background="@color/btn_redeem"/>

        <ImageView
            android:layout_width="51dp"
            android:layout_height="35dp"
            android:src="@drawable/ic_like"
            android:id="@+id/like"
            />
        <ImageView
            android:layout_width="51dp"
            android:layout_height="35dp"
            android:src="@drawable/ic_share"
            android:id="@+id/share"
             />


    </LinearLayout>

score 0 · Accepted Answer · edited May 23 '17 at 12:18

Run

@Override
        protected void onPostExecute(Void aVoid) {
            adapter = new CompanyCardRecycleViewAdapterClass(this,rowListItem);
            recyclerView.setAdapter(adapter);
        }

You are setting up empty list on the beginning. notifyDataSetChange does not work the way you expecting. You should return array from AsyncTask or update Adapter onPostExecute.

More elegant alternative you can find here: https://stackoverflow.com/a/35148283/6159609

CardView doesn't show on my RecycleView when pushing data from PHP/MySQL locally

1 Answers1