fix: Discovery WebViews Issues (#1828)

- Horizontal scrolling conflicted with vertical scrolling, causing
 pull-to-refresh issues.
- WebViews were not functioning properly with data.
- Back navigation did not work as expected in the webview.

Fixes: LEARNER-9636 | LEARNER-9637

OpenEdXMobile/src/main/java/org/edx/mobile/view/WebViewDiscoverFragment.java

@@ -3,13 +3,13 @@
 import android.os.Bundle;
 import android.text.TextUtils;
 import android.util.TypedValue;
-import android.view.KeyEvent;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
 import android.view.ViewTreeObserver;
 import android.webkit.URLUtil;
 
+import androidx.activity.OnBackPressedCallback;
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 
@@ -39,6 +39,20 @@ public class WebViewDiscoverFragment extends BaseWebViewFragment {
     protected FragmentWebviewDiscoveryBinding binding;
     private ViewTreeObserver.OnScrollChangedListener onScrollChangedListener;
 
+    private final OnBackPressedCallback onBackPressedCallback = new OnBackPressedCallback(false) {
+        @Override
+        public void handleOnBackPressed() {
+            if (binding.webview.canGoBack()) {
+                binding.webview.goBack();
+            } else {
+                // Disable the current callback to enable triggering the callback on the
+                // MainTabsDashboardFragment
+                onBackPressedCallback.setEnabled(false);
+                requireActivity().onBackPressed();
+            }
+        }
+    };
+
     @Nullable
     @Override
     public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
@@ -51,7 +65,9 @@ public void onViewCreated(View view, Bundle savedInstanceState) {
         super.onViewCreated(view, savedInstanceState);
         initTitle();
         setWebViewActionListener();
-        setWebViewBackPressListener();
+        requireActivity().getOnBackPressedDispatcher().addCallback(
+                getViewLifecycleOwner(), onBackPressedCallback
+        );
 
         // Check for search query in extras
         String searchQueryExtra = null;
@@ -118,18 +134,6 @@ public void onUserNotLoggedIn(@NonNull String courseId, boolean emailOptIn) {
                 }));
     }
 
-    private void setWebViewBackPressListener() {
-        binding.webview.setOnKeyListener((v, keyCode, event) -> {
-            if (event.getAction() == KeyEvent.ACTION_DOWN) {
-                if (keyCode == KeyEvent.KEYCODE_BACK && binding.webview.canGoBack()) {
-                    binding.webview.goBack();
-                    return true;
-                }
-            }
-            return false;
-        });
-    }
-
     @Override
     public void onSaveInstanceState(Bundle outState) {
         if (URLUtil.isValidUrl(binding.webview.getUrl())) {
@@ -191,6 +195,18 @@ public void onStart() {
                 });
     }
 
+    @Override
+    public void onResume() {
+        super.onResume();
+        onBackPressedCallback.setEnabled(true);
+    }
+
+    @Override
+    public void onPause() {
+        super.onPause();
+        onBackPressedCallback.setEnabled(false);
+    }
+
     @Override
     public void onStop() {
         super.onStop();