Android studio - items in second activity not showing

Question

The button and two TextViews will not show up when I navigate to the second activity. They do show up in Design view. I've looked at similar articles but cannot figure out the issue. I'm using Java. Thank you

Main.java

package com.example.cybersecgame;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.content.Intent;
import android.view.View;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {

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

        Button button = (Button) findViewById(R.id.button);
        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                startActivity(new Intent(MainActivity.this, SecondActivity.class));
            }
        });
    }
}

SecondActivity.java

package com.example.cybersecgame;

import static com.example.cybersecgame.R.layout.activity_second;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;

public class SecondActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(activity_second);
    }
}

Answer 1

First of all setContentView(activity_second) is wrong and setContentView(R.layout.activity_second) is the correct one.

Also setContentView(R.layout.activity_second) is not enough to load the Button and the TextView. You have to initialize them inside the onCreate method using findViewById(R.id.text_view).

The TextView IDs in the code are an example. You should use your own IDs which are defined in layout activity_second.xml.

package com.example.cybersecgame;
import static com.example.cybersecgame.R.layout.activity_second;
import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;

Button mButton;
TextView mTextView1, mTextView2;

public class SecondActivity extends AppCompatActivity {

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

        mButton = findViewById(R.id.button);
        mTextView1 = findViewById(R.id.text_view_1);
        mTextView2 = findViewById(R.id.text_view_2);

    }
}