Android RecyclerView with Expand Collapse and Click Event

 
         
		
package com.trickuweb.expandcollapse;

import androidx.appcompat.app.AppCompatActivity;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;

import android.net.Uri;
import android.os.Bundle;

import java.util.ArrayList;
import java.util.List;

public class MainActivity extends AppCompatActivity {
    RecyclerView recyclerView;
    List<FormulaModel> formulaList;

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

        initData();
        initRecyclerView();
    }

    private void initRecyclerView() {
        FormulaAdapter formulaAdapter = new FormulaAdapter(this, formulaList);
        recyclerView.setLayoutManager(new LinearLayoutManager(this));
        recyclerView.setAdapter(formulaAdapter);
    }

    private void initData() {
        formulaList = new ArrayList<>();

        Uri path1 = Uri.parse("android.resource://com.trickuweb.expandcollapse/" + R.drawable.basictrigformulas);
        Uri path2 = Uri.parse("android.resource://com.trickuweb.expandcollapse/" + R.drawable.evenoddformula);
        Uri path3 = Uri.parse("android.resource://com.trickuweb.expandcollapse/" + R.drawable.cosinerule);
        Uri path4 = Uri.parse("android.resource://com.trickuweb.expandcollapse/" + R.drawable.firstquadrant);

        formulaList.add(new FormulaModel("Basic Trigonometry Formulas",
                path1.toString()));
        formulaList.add(new FormulaModel("Even Odd Formula",
                path2.toString()));
        formulaList.add(new FormulaModel("Cosine Rule",
                path3.toString()));
        formulaList.add(new FormulaModel("First Quadrant",
                path4.toString()));

    }
}

		
            
         
    

 
         
			

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">


    <androidx.recyclerview.widget.RecyclerView
        android:id="@+id/recyclerViewFormula"
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>

</androidx.constraintlayout.widget.ConstraintLayout>

		
            
         
    

 
         
			
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:id="@+id/parent_layout"
    android:padding="8dp">


        <androidx.constraintlayout.widget.ConstraintLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content">

            <TextView
                android:id="@+id/textViewMonth"
                android:layout_width="0dp"
                android:layout_height="wrap_content"
                android:background="?attr/selectableItemBackground"
                android:padding="8dp"
                android:text="Name"
                android:textSize="16dp"
                android:paddingRight="6dp"
                android:textAppearance="@style/TextAppearance.AppCompat.Body1"
                android:textColor="@color/colorPrimaryDark"
                app:layout_constraintBottom_toTopOf="@+id/expandableLayout"
                app:layout_constraintEnd_toEndOf="parent"
                app:layout_constraintStart_toStartOf="parent"
                app:layout_constraintTop_toTopOf="parent" />

            <androidx.constraintlayout.widget.ConstraintLayout
                android:id="@+id/expandableLayout"
                android:layout_width="0dp"
                android:layout_height="wrap_content"
                android:visibility="visible"
                app:layout_constraintEnd_toEndOf="parent"
                app:layout_constraintHorizontal_bias="0.0"
                app:layout_constraintStart_toStartOf="parent"
                app:layout_constraintTop_toBottomOf="@id/textViewMonth">


                <ImageView
                    android:id="@+id/formulaImage"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:src="@drawable/cosinerule"
                    app:layout_constraintEnd_toEndOf="parent"
                    app:layout_constraintStart_toStartOf="parent"
                    app:layout_constraintTop_toTopOf="parent" />

            </androidx.constraintlayout.widget.ConstraintLayout>

        </androidx.constraintlayout.widget.ConstraintLayout>

</LinearLayout>
		
            
         
    

 
         
			

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'androidx.appcompat:appcompat:1.1.0'
    implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'androidx.test.ext:junit:1.1.1'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'
    implementation 'androidx.recyclerview:recyclerview:1.1.0'
    implementation 'com.squareup.picasso:picasso:2.71828'
}

		
            
         
    

 
         
			

package com.trickuweb.expandcollapse;

public class FormulaModel {

    private String name;
    private String pic;
    private boolean expanded;

    public FormulaModel(String name, String pic) {
        this.name = name;
        this.pic = pic;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getPic() {
        return pic;
    }

    public void setPic(String pic) {
        this.pic = pic;
    }

    public boolean isExpanded() {
        return expanded;
    }

    public void setExpanded(boolean expanded) {
        this.expanded = expanded;
    }

    @Override
    public String toString() {
        return "FormulaModel{" +
                "name='" + name + '\'' +
                ", pic='" + pic + '\'' +
                ", expanded=" + expanded +
                '}';
    }
}


		
            
         
    

 
         
			

package com.trickuweb.expandcollapse;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.TextView;
import android.widget.Toast;

import com.squareup.picasso.Picasso;
import java.util.List;
import androidx.annotation.NonNull;
import androidx.constraintlayout.widget.ConstraintLayout;
import androidx.recyclerview.widget.RecyclerView;

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

    List<FormulaModel> formulaList;
    Context mContext;

    public FormulaAdapter(Context mContext, List<FormulaModel> formulaList) {
        this.formulaList = formulaList;
        this.mContext = mContext;
    }

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

    @Override
    public void onBindViewHolder(@NonNull final ViewHolder holder, int position) {
        FormulaModel formula = formulaList.get(position);
        holder.textViewMonth.setText(formula.getName());

        Picasso.get().load(formula.getPic()).placeholder(R.drawable.cosinerule).error(R.drawable.cosinerule).into(holder.imageViewName);

//        holder.linearLayout.setOnClickListener(new View.OnClickListener() {
//            @Override
//            public void onClick(View v) {
//                Toast.makeText(mContext,holder.textViewMonth.getText(),Toast.LENGTH_SHORT).show();
//            }
//        });

//        boolean isExpanded = formulaList.get(position).isExpanded();
//        holder.expandableLayout.setVisibility(isExpanded ? View.VISIBLE : View.GONE);
    }

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

    class ViewHolder extends RecyclerView.ViewHolder {

        ConstraintLayout expandableLayout;
        TextView textViewMonth;
        ImageView imageViewName;
        LinearLayout linearLayout;

        public ViewHolder(@NonNull final View itemView) {
            super(itemView);

            textViewMonth = itemView.findViewById(R.id.textViewMonth);
            imageViewName = itemView.findViewById(R.id.formulaImage);
            expandableLayout = itemView.findViewById(R.id.expandableLayout);
            linearLayout =itemView.findViewById(R.id.parent_layout);

//            textViewMonth.setOnClickListener(new View.OnClickListener() {
//                @Override
//                public void onClick(View view) {
//                    FormulaModel formula = formulaList.get(getAdapterPosition());
//                    formula.setExpanded(!formula.isExpanded());
//                    notifyItemChanged(getAdapterPosition());
//                }
//            });
        }
    }
}