package com.example.expandablecardview;
import android.os.Bundle;
import android.transition.AutoTransition;
import android.transition.TransitionManager;
import android.view.View;
import android.widget.ImageButton;
import android.widget.LinearLayout;
import androidx.appcompat.app.AppCompatActivity;
import androidx.cardview.widget.CardView;

public class MainActivity extends AppCompatActivity {
    ImageButton arrow;
    LinearLayout hiddenView;
    CardView cardView;

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

        cardView = findViewById(R.id.base_cardview);
        arrow = findViewById(R.id.arrow_button);
        hiddenView = findViewById(R.id.hidden_view);

        arrow.setOnClickListener(view -> {
            // If the CardView is already expanded, set its visibility
            // to gone and change the expand less icon to expand more.
            if (hiddenView.getVisibility() == View.VISIBLE) {
                // The transition of the hiddenView is carried out by the TransitionManager class.
                // Here we use an object of the AutoTransition Class to create a default transition
                TransitionManager.beginDelayedTransition(cardView, new AutoTransition());
                hiddenView.setVisibility(View.GONE);
                arrow.setImageResource(R.drawable.more);
            }

            // If the CardView is not expanded, set its visibility to
            // visible and change the expand more icon to expand less.
            else {
                TransitionManager.beginDelayedTransition(cardView, new AutoTransition());
                hiddenView.setVisibility(View.VISIBLE);
                arrow.setImageResource(R.drawable.less); }
        });
    }
}