在单个活动中访问多个布局的元素

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">
    
    <TextView
        android:id="@+id/textView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Main Layout" />
    
    <Button
        android:id="@+id/switchButton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Switch Layout" />
</LinearLayout>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">
    
    <TextView
        android:id="@+id/textView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Alternative Layout" />
    
    <Button
        android:id="@+id/switchButton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Switch Back" />
</LinearLayout>

public class MainActivity extends AppCompatActivity {
    private boolean isMainLayout = true;

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

        Button switchButton = findViewById(R.id.switchButton);
        switchButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                switchLayout();
            }
        });
    }

    private void switchLayout() {
        LayoutInflater inflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        View newView;

        if (isMainLayout) {
            newView = inflater.inflate(R.layout.alternative_layout, null);
        } else {
            newView = inflater.inflate(R.layout.activity_main, null);
        }

        ViewGroup root = (ViewGroup) findViewById(android.R.id.content);
        root.removeAllViews();
        root.addView(newView);

        isMainLayout = !isMainLayout;
    }
}