on back button pressed webview fragment is movie back to previous fragment instead of previous webpage

Question

I am A Beginner in android development, actually I have a fragment with webview. My issue is when I am in fragment and click back button it is not going back to previous web page instead it is going back to previous fragment. so please help me in fixing this.

Here is my Main Activity Code :

public class MainActivity extends AbsRuntimePermission implements NavigationView.OnNavigationItemSelectedListener {
    //, GoogleApiClient.OnConnectionFailedListener {

    private static final int REQUEST_PERMISSION = 10;
    private Toolbar toolBar;
    private NavigationView navDrawer;
    private DrawerLayout drawerLayout;
    private ActionBarDrawerToggle drawerToggle;
    private FirebaseAuth.AuthStateListener authListener;
    private FirebaseAuth auth;
    private View btnLogOut;
    private int selectedItem;
    private FirebaseDatabase mFirebaseDatabase;
    private DatabaseReference myRef;
    //  private GoogleApiClient googleApiClient;
    private FloatingActionButton fab;
    private CoordinatorLayout coordinatorLayout;
    private HomeFragment homeFragment=new HomeFragment();

    final String TAG = this.getClass().getName();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        coordinatorLayout = (CoordinatorLayout) findViewById(R.id.coordinatorLayout);
        auth = FirebaseAuth.getInstance();
        final FirebaseUser user = auth.getCurrentUser();
        String userID = user.getUid();
        // Check if no view has focus:
        View view = this.getCurrentFocus();
        if (view != null) {
            InputMethodManager imm = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
            imm.hideSoftInputFromWindow(view.getWindowToken(), 0);
        }
        fab = (FloatingActionButton) findViewById(R.id.fab);
        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Intent intent = new Intent(MainActivity.this, Contact_FAB.class);
                startActivity(intent);
            }
        });
        FragmentTransaction tx = getSupportFragmentManager().beginTransaction();
        tx.replace(R.id.main_content, homeFragment);
        tx.commit();
        final WebView webView = (WebView) findViewById(R.id.WV);
        WebSettings webSettings = webView.getSettings();
        webSettings.setJavaScriptEnabled(true);
        webView.setWebViewClient(new WebViewClient() {
            public void onPageStarted(WebView view, String url, Bitmap favicon) {
            }

            public void onPageFinished(WebView view, String url) {
                // do your stuff here}
                @Override
                public void onReceivedError (WebView view,int errorCode, String description, String
                failingUrl){
                    super.onReceivedError(view, errorCode, description, failingUrl);
                }
            });

    webView.loadUrl("https://google.co.in");

            requestAppPermissions(new String[] {
                Manifest.permission.READ_CONTACTS,
                        Manifest.permission.READ_EXTERNAL_STORAGE,
                        Manifest.permission.WRITE_EXTERNAL_STORAGE
            },
            R.string.msg,REQUEST_PERMISSION);

            toolBar =(Toolbar)

            findViewById(R.id.app_bar);

            setSupportActionBar(toolBar);

            // If a notification message is tapped, any data accompanying the notification
            // message is available in the intent extras. In this project the launcher
            // intent is fired when the notification is tapped, so any accompanying data would
            // be handled here. If you want a different intent fired, set the click_action
            // field of the notification message to the desired intent. The launcher intent
            // is used when no click_action is specified.
            //
            // Handle possible data accompanying notification message.
    if(

            getIntent().

            getExtras() !=null)

            {
                for (String key : getIntent().getExtras().keySet()) {
                    String value = getIntent().getExtras().getString(key);
                    if (key.equals("AnotherActivity") && value.equals("True")) {
                        Intent intent = new Intent(this, AnotherActivity.class);
                        intent.putExtra("value", value);
                        startActivity(intent);
                        finish();
                    }

                }
            }

            // subscribeToPushService();

            drawerLayout =(DrawerLayout)

            findViewById(R.id.drawer_layout);

            navDrawer =(NavigationView)

            findViewById(R.id.menu_drawer);
    navDrawer.setNavigationItemSelectedListener(this);
            drawerToggle =new

            ActionBarDrawerToggle(this,drawerLayout, toolBar, R.string.drawer_open, R.string.drawer_close);
    drawerLayout.setDrawerListener(drawerToggle);
    drawerToggle.syncState();
            selectedItem =savedInstanceState ==null?R.id.nav_item_1 :savedInstanceState.getInt("selectedItem");

        }


        @Override
        public boolean onNavigationItemSelected (MenuItem menuItem){
            menuItem.setChecked(true);
            selectedItem = menuItem.getItemId();
            Fragment fragment = null;
            switch (selectedItem) {
                case R.id.nav_item_1:
                    fragment = new HomeFragment();
                    break;
                case R.id.nav_item_2:
                    fragment = new MicrosoftDskFragment();
                    break;
                case R.id.nav_item_3:
                    fragment = new GoogleDskFragment();
                    break;
                case R.id.nav_item_4:
                    fragment = new AppleDskFragment();
                    break;
                case R.id.nav_item_5:
                    fragment = new OthersDskFragment();
                    break;
                case R.id.nav_item_6:
                    fragment = new MobiSpecsFragment();
                    break;
                case R.id.nav_item_8:
                    Intent intent = new Intent(MainActivity.this, About.class);
                    startActivity(intent);
                    break;
                default:
                    break;
            }

            if (!DetectConnection.checkInternetConnection(MainActivity.this)) {
                Toast.makeText(MainActivity.this, "Plz check your network connectivity", Toast.LENGTH_SHORT).show();
            } else {

                if (fragment != null) {

                    FragmentManager fragmentManager = getSupportFragmentManager();
                    FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
                    fragmentTransaction.replace(R.id.main_content, fragment);
                    fragmentTransaction.addToBackStack(null);
                    fragmentTransaction.commit();
                }
            }

            drawerLayout.closeDrawer(GravityCompat.START);
            return true;
        }

        boolean twice = false;

        @Override
        public void onBackPressed () {
            DrawerLayout layout = (DrawerLayout) findViewById(R.id.drawer_layout);

            if (layout.isDrawerOpen(GravityCompat.START)) {
                layout.closeDrawer(GravityCompat.START);
            } else {
                if (getSupportFragmentManager().getBackStackEntryCount() > 0) {
                    getSupportFragmentManager().popBackStack();
                } else {
                    Log.d(TAG, "click");

                    if (twice == true) {
                        Intent intent = new Intent(Intent.ACTION_MAIN);
                        intent.addCategory(Intent.CATEGORY_HOME);
                        intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
                        startActivity(intent);
                        finish();
                        System.exit(0);
                    }
                    twice = true;
                    Log.d(TAG, "twice: " + twice);

                    //super.onBackPressed();
                    Toast.makeText(MainActivity.this, "Please Press Again To Exit", Toast.LENGTH_SHORT).show();

                    new Handler().postDelayed(new Runnable() {
                        @Override
                        public void run() {
                            twice = false;
                            Log.d(TAG, "twice: " + twice);
                        }
                    }, 3000);

                }
            }
        }

        @Override
        public boolean onKeyDown ( int keyCode, KeyEvent event){
            if (event.getAction() == KeyEvent.ACTION_DOWN) {
                switch (keyCode) {
                    case KeyEvent.KEYCODE_BACK:
                        homeFragment.OnKeyDown(keyCode);
                        return true;
                }
            }
            return super.onKeyDown(keyCode, event);
        }


        @Override
        public boolean onCreateOptionsMenu (Menu menu){
            // Inflate the menu; this adds items to the action bar if it is present.

            getMenuInflater().inflate(R.menu.menu_main, menu);

            return super.onCreateOptionsMenu(menu);
        }

        @Override
        public boolean onOptionsItemSelected (MenuItem item){
            // Handle action bar item clicks here. The action bar will
            // automatically handle clicks on the Home/Up button, so long
            // as you specify a parent activity in AndroidManifest.xml.
            int id = item.getItemId();


            //noinspection SimplifiableIfStatement
            if (id == R.id.profile) {
                Intent intent = new Intent(MainActivity.this, Profile.class);
                startActivity(intent);
                return true;
            }


            return super.onOptionsItemSelected(item);
        }


        @Override
        public void onSaveInstanceState (Bundle outState, PersistableBundle outPersistentState){
            super.onSaveInstanceState(outState, outPersistentState);

            outState.putInt("selectedItem", selectedItem);
        }

        @Override
        public void onPermissionsGranted ( int requestCode){
            //Do anything when permisson granted
            //   Toast.makeText(getApplicationContext(), "Permission granted", Toast.LENGTH_LONG).show();
        }


/*    @Override
    public void onConnectionFailed(@NonNull ConnectionResult connectionResult) {

    }

*/

    }
}

And Here Is My Home Fragment Code :

@SuppressWarnings("ALL")

public class HomeFragment extends Fragment {

WebView webView;
SwipeRefreshLayout swipeView;

public HomeFragment() {
    // Required empty public constructor
}

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

}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    View rootView = inflater.inflate(R.layout.fragment_home, container, false);
    swipeView = (SwipeRefreshLayout) rootView.findViewById(R.id.container);
    webView = (WebView) rootView.findViewById(R.id.webView);


    webView.getSettings().setJavaScriptEnabled(true);
    // Inflate the layout for this fragment
    webView.loadUrl("https://google.co.in");

    webView.setWebViewClient(new WebViewClient() {
        @Override
        public void onReceivedError(WebView view, int errorCode, String description, String failingUrl) {
            webView.stopLoading();
            webView.clearView();
            Intent intent = new Intent(getActivity(), ErrorActivity.class);
            startActivity(intent);
            swipeView.setEnabled(false);
            super.onReceivedError(view, errorCode, description, failingUrl);

        }

        public void onPageFinished(WebView view, String url) {
            // do your stuff here
            swipeView.setRefreshing(false);

        }

    });


    swipeView.setColorScheme(android.R.color.holo_blue_dark, android.R.color.holo_blue_light);
    swipeView.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {

        @Override
        public void onRefresh() {
            swipeView.setRefreshing(true);

            (new Handler()).postDelayed(new Runnable() {
                @Override
                public void run() {
                    webView.loadUrl("javascript:window.location.reload( true )");

                }
            }, 2000);
        }
    });
    return rootView;
}
    @Override
    public void onAttach (Activity activity){
        super.onAttach(activity);
    }

    @Override
    public void onDetach () {
        super.onDetach();
    }

  public void OnKeyDown(int keyCode) {
    if (webView != null) {
        if (webView.canGoBack()) {
            webView.goBack();

        } else {
            getActivity().onBackPressed();
        }
    }
}
}

Try to add something like webView.canGoBack() in onBackPressed() Ref : https://stackoverflow.com/questions/42749269/back-button-in-android-webview-within-a-fragment — VVB, Oct 13 '17 at 10:10

score 0 · Answer 1 · answered Oct 13 '17 at 03:59

In your onNavigationItemSelected when the FragmentManager replaces the Fragment, don't add it to the backstack:

FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
                    fragmentTransaction.replace(R.id.main_content, fragment);
                    fragmentTransaction.commit();

If you add it to the backstack, that means you add that Fragment to the history stack of the Activity, action which is reverted when you press the back button. So every time you add a new Fragment, the stack will be like this: [fragment1][fragment2][fragment3], and if you press the back button, it will remove the last added action, so removing the [fragment3] will show you the [fragment2].

Hope this helps.

removing add to back stack doesn't fix my issue – Rohith Rebel Oct 13 '17 at 06:33 — Rohith Rebel, Oct 13 '17 at 06:33

score 0 · Answer 2 · answered Oct 13 '17 at 05:14

0

Create a method in your fragment like to perform action when keys are pressed

public void OnKeyDown(int keyCode){
   if (mWebView.canGoBack()) {
       mWebView.goBack();
   } else {
       getActivity().onBackPressed();
   }
}

And in your corresponding activity override keyDown method and handle the key press

@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
    if (event.getAction() == KeyEvent.ACTION_DOWN) {
        switch (keyCode) {
            case KeyEvent.KEYCODE_BACK:
                yourFagmentObject.OnKeyDown(keyCode);
                return true;
        }
    }
    return super.onKeyDown(keyCode, event);
}

Remove the webView.setOnKeyListener(new View.OnKeyListener() from the webViewFragment.

answered Oct 13 '17 at 05:14

Sharath kumar

4,064
1
14
20

Thanx Will try that – Rohith Rebel Oct 13 '17 at 06:02
; expected in fragment – Rohith Rebel Oct 13 '17 at 06:25
cannot resolve method OnKeyDown(int) in main activity – Rohith Rebel Oct 13 '17 at 06:26
onKeyDown is a overriden method in acitivity..can u update code? – Sharath kumar Oct 13 '17 at 06:40
What is AbsRuntimePermission?main activity is not extending activity or appcompactivity? – Sharath kumar Oct 13 '17 at 07:03
public abstract class AbsRuntimePermission extends AppCompatActivity – Rohith Rebel Oct 13 '17 at 07:05
and mainActivity extends AbsRuntimePermission class – Rohith Rebel Oct 13 '17 at 07:06
tried MainActivity Extends Activity/AppCompatActivity but same issue – Rohith Rebel Oct 13 '17 at 07:08
I check your code everything works fine..onkeyDown is overridden method in activity.If you are getting error and override that method and then add the code. – Sharath kumar Oct 13 '17 at 07:08
public void OnKeyDown(int keyCode){ if (mWebView.canGoBack()) { mWebView.goBack(); } else { getActivity().onBackPressed(); } } in this part in fragment iam getting error (; expected) – Rohith Rebel Oct 13 '17 at 07:09
Its some bug or something..override method yourself and add the code – Sharath kumar Oct 13 '17 at 07:09
You have placed method inside method so that error..check updated code. – Sharath kumar Oct 13 '17 at 07:16
tried same like u updated getting error non static method OnKeyDown(int) cannot be referenced from static context – Rohith Rebel Oct 13 '17 at 08:39
non static method OnKeyDown(int) cannot be referenced from static context this is from main activity – Rohith Rebel Oct 13 '17 at 08:42
you cannot call a method without object..I said homeFragment object,not homefragment. see the updated code.do like that – Sharath kumar Oct 13 '17 at 08:48
oh sorry i will try it now – Rohith Rebel Oct 13 '17 at 08:52
on runtime getting this error java.lang.NullPointerException: Attempt to invoke virtual method 'boolean android.webkit.WebView.canGoBack()' on a null object reference – Rohith Rebel Oct 13 '17 at 08:58
check the updated code. webview object should be global – Sharath kumar Oct 13 '17 at 09:05
treid updated code but still getting java.lang.NullPointerException: Attempt to invoke virtual method 'boolean android.webkit.WebView.canGoBack()' on a null object reference – Rohith Rebel Oct 13 '17 at 09:19
Tried that after doing that back button isn't working at all – Rohith Rebel Oct 13 '17 at 09:33
It shouldn't have given error.Try this updated code and let me know. – Sharath kumar Oct 13 '17 at 09:44
no not working only on back pressed method i have used in main activity is working . webview isn't going back – Rohith Rebel Oct 13 '17 at 09:53
yeah tried that updated code webView.setOnKeyListener(new View.OnKeyListener(){ public boolean onKey(View v, int keyCode, KeyEvent event) { if (keyCode == KeyEvent.KEYCODE_BACK && event.getAction() == MotionEvent.ACTION_UP && webView.canGoBack()) { webView.goBack(); return true; } return false; } }); – Rohith Rebel Oct 13 '17 at 10:00
not getting any error but simpley webview isn't going back , only on back pressed method i have used in main activity is working – Rohith Rebel Oct 13 '17 at 10:01

on back button pressed webview fragment is movie back to previous fragment instead of previous webpage

2 Answers2