Android WebView Preserve content when fragment is changed

What you can try is the following:

Remembering a bit the life cycle of the fragment, under the idea that you want to realize, you can move the code that you have the onCreate(). Remember that this method allows you to initialize some things and when you return to this fragment you will not re-execute this method if and only if it was already created. With the idea that you have as your fragment was already created, it will not be re-executed (restarted). For now you have it in the method . onCreateView()I would recommend that you move it to the onCreate(). Then when you go to call some fragment, remember that we can override ( method replace()) of fragmentManager and we can agregar( method add()) of fragmentManager. For your case, what is best for you is to make a add(). I leave you an example:

To add :

getSupportFragmentManager().beginTransaction()
                    .add(R.id.fragment_container, firstFragment).commit();

To replace :

getSupportFragmentManager().beginTransaction()
                    .replace(R.id.fragment_container, firstFragment).commit();

update

Example :

public class GalleryFragment extends Fragment {

    WebView miVisorWeb;

    String url = "https://www.google.com/";

   @Override
   public void onCreate(@Nullable Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);

       //inicializar variables, como la url que quieres cargar.
       // Algunas otras cosas que quieres que solo se llame una vez
       url = "https://www.google.com/";
   }

   public View onCreateView(@NonNull LayoutInflater inflater,
                     ViewGroup container, Bundle savedInstanceState) {
       // Aqui inicializar tu vistas y componentes
       View root = inflater.inflate(R.layout.fragment_gallery, container,false);

       miVisorWeb = (WebView) root.findViewById(R.id.webViewGoogle);

       return root;
    }


@Override
public void onViewCreated(View view, @Nullable Bundle     savedInstanceState) {
    super.onViewCreated(view, savedInstanceState);

     //Aqui va todo el código restante
     miVisorWeb.requestFocus();
     WebSettings webSettings = miVisorWeb.getSettings();
     webSettings.setJavaScriptEnabled(true);
     webSettings.setCacheMode(LOAD_CACHE_ELSE_NETWORK);
     webSettings.setAppCacheEnabled(true);

     miVisorWeb.loadUrl(url.toString());
     CookieManager.getInstance().setAcceptCookie(true);
     // Bloque 2
     miVisorWeb.setWebViewClient( new WebViewClient(){
       public boolean shouldOverrideUrlLoading(WebView view, String url) {
         view.loadUrl(url);
         return false;
       }
     });

      miVisorWeb.setOnKeyListener(new View.OnKeyListener(){
          @Override
          public boolean onKey(View v, int keyCode, KeyEvent event){
              if(event.getAction() == KeyEvent.ACTION_DOWN){
                WebView webView = (WebView) v;
                switch(keyCode){
                    case KeyEvent.KEYCODE_BACK:
                        if(webView.canGoBack()){
                            webView.goBack();
                            return true;
                        }
                        break;
                 }
              }

              return false;
           }
       });
    
    } 
}

Now when you want to call another fragment what you have to do is the following:

// Add the fragment to the 'fragment_container' FrameLayout
            supportFragmentManager.beginTransaction()
                    .add(R.id.fragment_container, firstFragment).addToBackStack(null).commit()

Remember that the parameter R.id.fragment_containeris the id of your fragment container and firstFragmentis the fragment you want to go to. Just replace those values ​​with the ones you have in your project

Then, citing your example. If you go back from B to A, the code you have in A will no longer be executed. Because it's only in the methodonCreate

Another way to work around so you're not handling fragments is to do it with activities. Following the same example of fragments. In your activity, let's call it A. You add all the code you have. Then just to pass to an activity B. you call startActivity. When you do back, the code you have in the method onCreateof activity A will not be executed either.

References: FragmentManager

I hope it helps you :)