fix duplicate items issue in listing

esoxjem · Dec 4, 2019 · b271d0a · b271d0a
1 parent 0537689
commit b271d0a
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Showing 2 changed files with 44 additions and 29 deletions.
diff --git a/app/src/main/java/com/esoxjem/movieguide/listing/MoviesListingFragment.java b/app/src/main/java/com/esoxjem/movieguide/listing/MoviesListingFragment.java
@@ -13,6 +13,7 @@
 import androidx.fragment.app.DialogFragment;
 import androidx.fragment.app.Fragment;
 import androidx.recyclerview.widget.GridLayoutManager;
+import androidx.recyclerview.widget.LinearLayoutManager;
 import androidx.recyclerview.widget.RecyclerView;
 
 import com.esoxjem.movieguide.BaseApplication;
@@ -22,6 +23,8 @@
 import com.esoxjem.movieguide.listing.sorting.SortingDialogFragment;
 import com.google.android.material.snackbar.Snackbar;
 
+import org.jetbrains.annotations.NotNull;
+
 import java.util.ArrayList;
 import java.util.List;
 
@@ -66,16 +69,6 @@ public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle sa
         View rootView = inflater.inflate(R.layout.fragment_movies, container, false);
         unbinder = ButterKnife.bind(this, rootView);
         initLayoutReferences();
-        moviesListing.addOnScrollListener(new RecyclerView.OnScrollListener() {
-            @Override
-            public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
-                super.onScrollStateChanged(recyclerView, newState);
-
-                if (!recyclerView.canScrollVertically(1)) {
-                    moviesPresenter.nextPage();
-                }
-            }
-        });
         return rootView;
     }
 
@@ -117,11 +110,26 @@ private void initLayoutReferences() {
         } else {
             columns = getResources().getInteger(R.integer.no_of_columns);
         }
-        RecyclerView.LayoutManager layoutManager = new GridLayoutManager(getActivity(), columns);
+        LinearLayoutManager layoutManager = new GridLayoutManager(getActivity(), columns);
 
         moviesListing.setLayoutManager(layoutManager);
         adapter = new MoviesListingAdapter(movies, this);
         moviesListing.setAdapter(adapter);
+
+        moviesListing.addOnScrollListener(new RecyclerView.OnScrollListener() {
+            @Override
+            public void onScrolled(@NotNull RecyclerView recyclerView, int dx, int dy) {
+                super.onScrolled(recyclerView, dx, dy);
+                int visibleItemCount = layoutManager.getChildCount();
+                int totalItemCount = layoutManager.getItemCount();
+                int firstVisibleItemPosition = layoutManager.findFirstVisibleItemPosition();
+
+                if ((visibleItemCount + firstVisibleItemPosition) >=
+                        totalItemCount && firstVisibleItemPosition >= 0) {
+                    moviesPresenter.nextPage();
+                }
+            }
+        });
     }
 
     @Override

diff --git a/app/src/main/java/com/esoxjem/movieguide/listing/MoviesListingPresenterImpl.java b/app/src/main/java/com/esoxjem/movieguide/listing/MoviesListingPresenterImpl.java
@@ -23,7 +23,7 @@ class MoviesListingPresenterImpl implements MoviesListingPresenter {
     private Disposable movieSearchSubscription;
     private int currentPage = 1;
     private List<Movie> loadedMovies = new ArrayList<>();
-    private boolean showingSearchResult = false;
+    private boolean isLoading = false;
 
     MoviesListingPresenterImpl(MoviesListingInteractor interactor) {
         moviesInteractor = interactor;
@@ -32,10 +32,7 @@ class MoviesListingPresenterImpl implements MoviesListingPresenter {
     @Override
     public void setView(MoviesListingView view) {
         this.view = view;
-        if (!showingSearchResult) {
-            displayMovies();
-        }
-
+        displayMovies();
     }
 
     @Override
@@ -45,8 +42,13 @@ public void destroy() {
     }
 
     private void displayMovies() {
-        EspressoIdlingResource.increment();
+        if (isLoading) return;
+
+        isLoading = true;
         showLoading();
+
+        EspressoIdlingResource.increment();
+
         fetchSubscription = moviesInteractor.fetchMovies(currentPage)
                 .subscribeOn(Schedulers.io())
                 .observeOn(AndroidSchedulers.mainThread())
@@ -58,15 +60,6 @@ private void displayMovies() {
                 .subscribe(this::onMovieFetchSuccess, this::onMovieFetchFailed);
     }
 
-    private void displayMovieSearchResult(@NonNull final String searchText) {
-        showingSearchResult = true;
-        showLoading();
-        movieSearchSubscription = moviesInteractor.searchMovie(searchText)
-                .subscribeOn(Schedulers.io())
-                .observeOn(AndroidSchedulers.mainThread())
-                .subscribe(this::onMovieSearchSuccess, this::onMovieSearchFailed);
-    }
-
     @Override
     public void firstPage() {
         currentPage = 1;
@@ -76,7 +69,7 @@ public void firstPage() {
 
     @Override
     public void nextPage() {
-        if (showingSearchResult)
+        if (isLoading)
             return;
         if (moviesInteractor.isPaginationSupported()) {
             currentPage++;
@@ -91,14 +84,22 @@ public void searchMovie(final String searchText) {
         } else {
             displayMovieSearchResult(searchText);
         }
+    }
 
+    private void displayMovieSearchResult(@NonNull final String searchText) {
+        isLoading = true;
+        showLoading();
+        movieSearchSubscription = moviesInteractor.searchMovie(searchText)
+                .subscribeOn(Schedulers.io())
+                .observeOn(AndroidSchedulers.mainThread())
+                .subscribe(this::onMovieSearchSuccess, this::onMovieSearchFailed);
     }
 
     @Override
     public void searchMovieBackPressed() {
-        if (showingSearchResult) {
-            showingSearchResult = false;
+        if (isLoading) {
             loadedMovies.clear();
+            isLoading = false;
             displayMovies();
         }
     }
@@ -115,13 +116,17 @@ private void onMovieFetchSuccess(List<Movie> movies) {
         } else {
             loadedMovies = new ArrayList<>(movies);
         }
+
         if (isViewAttached()) {
             view.showMovies(loadedMovies);
         }
+
+        isLoading = false;
     }
 
     private void onMovieFetchFailed(Throwable e) {
         view.loadingFailed(e.getMessage());
+        isLoading = false;
     }
 
     private void onMovieSearchSuccess(List<Movie> movies) {
@@ -130,10 +135,12 @@ private void onMovieSearchSuccess(List<Movie> movies) {
         if (isViewAttached()) {
             view.showMovies(loadedMovies);
         }
+        isLoading = false;
     }
 
     private void onMovieSearchFailed(Throwable e) {
         view.loadingFailed(e.getMessage());
+        isLoading = false;
     }
 
     private boolean isViewAttached() {