Fixed drag and dropping using indicators

app/src/main/java/gr/thmmy/mthmmy/activities/bookmarks/BookmarksActivity.java

@@ -78,9 +78,9 @@ public class BookmarksActivity extends BaseActivity {
     }
 
 
-    public void swapBookmarksAfterReorder(Bookmark first, Bookmark second)
+    public void updateBookmarks(ArrayList<Bookmark> update_bookmarks)
     {
-        this.swapBookmarks(first, second);
+        this.updateBookmarksOnReorder(update_bookmarks);
     }
 
     private boolean onTopicInteractionListener(String interactionType, Bookmark bookmarkedTopic) {

app/src/main/java/gr/thmmy/mthmmy/activities/bookmarks/BookmarksAdapter.java

@@ -24,14 +24,12 @@ import gr.thmmy.mthmmy.model.Bookmark;
 public class BookmarksAdapter extends DragItemAdapter<ArrayList<Bookmark>, BookmarksAdapter.BookmarksViewHolder>
 {
     private final BookmarksFragment m_fragment;
-    private final ArrayList<Bookmark> m_bookMarks;
     private final Drawable m_notificationsEnabled;
     private final Drawable m_notificationsDisabled;
 
-    public BookmarksAdapter(BookmarksFragment fragment, ArrayList<Bookmark> bookmarks, Drawable noteEnabled, Drawable noteDisabled)
+    public BookmarksAdapter(BookmarksFragment fragment, Drawable noteEnabled, Drawable noteDisabled)
     {
         this.m_fragment = fragment;
-        this.m_bookMarks = bookmarks;
         this.m_notificationsEnabled = noteEnabled;
         this.m_notificationsDisabled = noteDisabled;
     }
@@ -39,7 +37,7 @@ public class BookmarksAdapter extends DragItemAdapter<ArrayList<Bookmark>, Bookm
     @Override
     public long getUniqueItemId(int position)
     {
-        return m_bookMarks.get(position).getId().hashCode();
+        return m_fragment.bookmarks.get(position).getId().hashCode();
     }
 
     @NonNull
@@ -55,18 +53,26 @@ public class BookmarksAdapter extends DragItemAdapter<ArrayList<Bookmark>, Bookm
     {
         super.onBindViewHolder(holder, position);
 
+        //If this is a drop indicator, use the dashed corner background.
+        if (m_fragment.bookmarks.get(position).getId().equals("-1"))
+        {
+            holder.itemView.findViewById(R.id.bookmark_dragable).setBackgroundResource(R.drawable.bookmark_row_dashed_bg);
+            holder.itemView.findViewById(R.id.toggle_notification).setVisibility(View.GONE);
+            holder.itemView.findViewById(R.id.remove_bookmark).setVisibility(View.GONE);
+        }
+
         //Check if bookMarks ArrayList Exists and is not empty.
-        if(m_bookMarks != null && !m_bookMarks.isEmpty())
+        if(m_fragment.bookmarks != null && !m_fragment.bookmarks.isEmpty())
         {
             //Check if the current bookmark exists and has a title.
-            if (m_bookMarks.get(position) != null && m_bookMarks.get(position).getTitle() != null)
+            if (m_fragment.bookmarks.get(position) != null && m_fragment.bookmarks.get(position).getTitle() != null)
             {
 
                 //Set the title.
-                holder.m_textView.setText(m_bookMarks.get(position).getTitle());
+                holder.m_textView.setText(m_fragment.bookmarks.get(position).getTitle());
 
                 //Set Notifications Enabled Image Indicator.
-                if (m_bookMarks.get(position).isNotificationsEnabled())
+                if (m_fragment.bookmarks.get(position).isNotificationsEnabled())
                     holder.m_noteView.setImageDrawable(m_notificationsEnabled);
 
                 //Set Notifications Disabled Image Indicator.
@@ -85,7 +91,7 @@ public class BookmarksAdapter extends DragItemAdapter<ArrayList<Bookmark>, Bookm
                         ((BookmarksActivity) activity).onFragmentRowInteractionListener(
                                 m_fragment.type,
                                 m_fragment.interactionClick,
-                                m_bookMarks.get(position));
+                                m_fragment.bookmarks.get(position));
                 });
 
 
@@ -93,7 +99,7 @@ public class BookmarksAdapter extends DragItemAdapter<ArrayList<Bookmark>, Bookm
                 holder.m_noteView.setOnClickListener(v -> {
 
                     //Toggle the current local instance.
-                    m_bookMarks.get(position).toggleNotificationsEnabled();
+                    m_fragment.bookmarks.get(position).toggleNotificationsEnabled();
 
                     //Get the fragment activity.
                     Activity activity = m_fragment.getActivity();
@@ -106,7 +112,7 @@ public class BookmarksAdapter extends DragItemAdapter<ArrayList<Bookmark>, Bookm
                         if (((BookmarksActivity) activity).onFragmentRowInteractionListener(
                                 m_fragment.type,
                                 m_fragment.interactionToggle,
-                                m_bookMarks.get(position)))
+                                m_fragment.bookmarks.get(position)))
                         {
                             holder.m_noteView.setImageDrawable(m_notificationsEnabled);
                         }
@@ -133,16 +139,16 @@ public class BookmarksAdapter extends DragItemAdapter<ArrayList<Bookmark>, Bookm
                         ((BookmarksActivity) activity).onFragmentRowInteractionListener(
                                 m_fragment.type,
                                 m_fragment.interactionRemove,
-                                m_bookMarks.get(position));
+                                m_fragment.bookmarks.get(position));
                         {
                             notifyItemRemoved(position);
-                            notifyItemRangeChanged(position, m_bookMarks.size());
+                            notifyItemRangeChanged(position, m_fragment.bookmarks.size());
-                            m_bookMarks.remove(m_bookMarks.get(position));
+                            m_fragment.bookmarks.remove(m_fragment.bookmarks.get(position));
                         }
                     }
 
                     //If the bookmarks are empty then show nothing marked.
-                    if (m_bookMarks.isEmpty())
+                    if (m_fragment.bookmarks.isEmpty())
                     {
                         m_fragment.showNothingBookmarked();
                     }
@@ -155,8 +161,8 @@ public class BookmarksAdapter extends DragItemAdapter<ArrayList<Bookmark>, Bookm
     @Override
     public int getItemCount()
     {
-        if (m_bookMarks != null)
+        if (m_fragment.bookmarks != null)
-         return m_bookMarks.size();
+         return m_fragment.bookmarks.size();
 
         return 0;
     }

app/src/main/java/gr/thmmy/mthmmy/activities/bookmarks/BookmarksFragment.java

@@ -39,7 +39,7 @@ public class BookmarksFragment extends Fragment {
 
     private TextView nothingBookmarkedTextView;
 
-    private ArrayList<Bookmark> bookmarks = null;
+    public ArrayList<Bookmark> bookmarks = null;
     public Type type;
     public String interactionClick, interactionToggle, interactionRemove;
 
@@ -107,13 +107,40 @@ public class BookmarksFragment extends Fragment {
         //Get the nothing bookmarked text view.
         nothingBookmarkedTextView = rootView.findViewById(R.id.nothing_bookmarked);
 
+        //Create the adapter.
+        BookmarksAdapter adapter = new BookmarksAdapter(this, notificationsEnabledButtonImage, notificationsDisabledButtonImage);
+
+        //Get the drag list view.
         DragListView mDragListView = (DragListView) rootView.findViewById(R.id.fragment_bookmarks_dragList);
 
+        //Set the Drag List Listener.
         mDragListView.setDragListListener(new DragListView.DragListListener()
         {
             @Override
             public void onItemDragStarted(int position)
             {
+                //Create a new array of bookmarks.
+                ArrayList<Bookmark> new_bookmarks = new ArrayList<Bookmark>();
+
+                //For each bookmark in the current bookmarks array.
+                for (int i = 0; i < bookmarks.size(); i++)
+                {
+                    //Create an indicator bookmark.
+                    Bookmark indicator = new Bookmark("Drop Here", "-1", true);
+
+                    //Add the indicator followed by the current actual bookmark.
+                    new_bookmarks.add(indicator);
+                    new_bookmarks.add(bookmarks.get(i));
+                }
+
+                //Replace the bookmarks with the new bookmarks that contains the indicators.
+                bookmarks = new_bookmarks;
+
+                //Add one last indicator.
+                bookmarks.add(new Bookmark("Drop Here", "-1", true));
+
+                //Notify the adapter that the bookmarks array has changed!
+                adapter.notifyDataSetChanged();
             }
 
             @Override
@@ -126,36 +153,71 @@ public class BookmarksFragment extends Fragment {
             public void onItemDragEnded(int fromPosition, int toPosition)
             {
 
+                //This is VERY IMPORTANT: Because I added indicator boxes
+                //in the onItemDragStarted, I need to recalculate the actual position
+                //of the started item (fromPosition) because it has changed!!!
+                int offset    = fromPosition + 1;
+                int actualPos = fromPosition + offset;
+
                 //If the drag and drop is not the same item.
-                if (fromPosition != toPosition)
+                if (actualPos != toPosition)
                 {
 
                     //Get the from bookmark.
-                    Bookmark from = bookmarks.get(fromPosition);
+                    Bookmark from = bookmarks.get(actualPos);
+                    Bookmark to   = bookmarks.get(toPosition);
 
-                    //Swap the from and to bookmarks.
+                    //You can only drop items in the indicator boxes!!!
-                    bookmarks.set(fromPosition, bookmarks.get(toPosition));
+                    //Indicator boxes are Bookmark objects with id "-1".
-                    bookmarks.set(toPosition, from);
+                    if (to.getId().equals("-1"))
+                    {
+                        //Swap the indicator with the actual.
+                        bookmarks.set(actualPos, to);
+                        bookmarks.set(toPosition, from);
+
+                        //Get the fragments activity.
+                        Activity unknownActivity = getActivity();
+
+                        //Update the order of the bookmarks in the preferences.
+                        if (unknownActivity instanceof BookmarksActivity)
+                        {
+                            //Cast to BookmarksActivity.
+                            BookmarksActivity activity = (BookmarksActivity)unknownActivity;
+
+                            //Update the preferences.
+                            activity.updateBookmarks(bookmarks);
+                        }
+                    }
 
-                    //Get the fragments activity.
+                    //------------------------Clean up the indicator boxes------------------------//
-                    Activity unknownActivity = getActivity();
+                }
 
-                    //Update the order of the bookmarks in the preferences.
+                //Find all the indicator boxes in the bookmarks array.
-                    if (unknownActivity instanceof BookmarksActivity)
+                ArrayList<Bookmark> books_to_delete = new ArrayList<Bookmark>();
-                    {
+                for (int i = 0; i < bookmarks.size(); i++)
-                        //Cast to BookmarksActivity.
+                {
-                        BookmarksActivity activity = (BookmarksActivity)unknownActivity;
+                    Bookmark book = bookmarks.get(i);
 
-                        //Call the swapBookmarksAfterReorder to apply the swapping changes to the preferences.
+                    if (book.getId().equals("-1"))
-                        activity.swapBookmarksAfterReorder( bookmarks.get(fromPosition), bookmarks.get(toPosition) );
+                        books_to_delete.add(book);
-                    }
+                }
+
+
+                //Remove all the indicators.
+                for (int i = 0; i < books_to_delete.size(); i++)
+                {
+                    bookmarks.remove(books_to_delete.get(i));
                 }
+
+                //------------------------Clean up the indicator boxes------------------------//
+
+                //Notify the adapter, because I made changes to the bookmarks array.
+                adapter.notifyDataSetChanged();
             }
         });
 
         //====================================This is the code for the Drag and Drop Functionality====================================//
         mDragListView.setLayoutManager(new LinearLayoutManager(getActivity()));
-        BookmarksAdapter adapter = new BookmarksAdapter(this, bookmarks, notificationsEnabledButtonImage, notificationsDisabledButtonImage);
         mDragListView.setAdapter(adapter, false);
         mDragListView.setCanDragHorizontally(false);
         //====================================This is the code for the Drag and Drop Functionality====================================//

app/src/main/java/gr/thmmy/mthmmy/base/BaseActivity.java

@@ -692,84 +692,43 @@ public abstract class BaseActivity extends AppCompatActivity {
     }
 
 
-    //TODO: Abstract reusable code: find the index of the first and second bookmark.
+    /*
-    protected void swapBookmarks(Bookmark first, Bookmark second)
+    * This method should only be called after reordering the bookmarks.
+    * It Re-creates the topicsBookmarked and boardsBookmarked arrays
+    * with the reordered bookmarks.
+    * */
+    protected void updateBookmarksOnReorder(ArrayList<Bookmark> updated_bookmarks)
     {
+        //Define to empty arrays.
+        ArrayList<Bookmark> newTopicBookmarks = new ArrayList<Bookmark>();
+        ArrayList<Bookmark> newBoardBookmarks = new ArrayList<Bookmark>();
 
-        //No need to check is second is a topics bookmark.
+        //For each bookmark in updated_bookmarks.
-        //because there is no way to drag and drop between topic and board.
+        for (int i = 0; i < updated_bookmarks.size(); i++)
-        if ( first.matchExists(topicsBookmarked) )
         {
-            //Find the index of the first and second bookmark.
+            //Get the current updated bookamrk.
-            int firstIndex = -1, secondIndex = -1;
+            Bookmark book = updated_bookmarks.get(i);
-            for (int i = 0; i < topicsBookmarked.size(); i++)
-            {
-
-                //Find the first index.
-                if (first.getId().equals(topicsBookmarked.get(i).getId()))
-                    firstIndex = i;
-
-                //Find the second index.
-                else if (second.getId().equals(topicsBookmarked.get(i).getId()))
-                    secondIndex = i;
-
-                //If both indexes found, stop.
-                if (firstIndex != -1 && secondIndex != -1)
-                    break;
-            }
-
-            //Assert, both indexes should have been found.
-            if (BuildConfig.DEBUG && !(firstIndex != -1 && secondIndex != -1)) {
-                throw new AssertionError("firstIndex and secondIndex must exist!");
-            }
 
-            //Temp store the first bookmark.
+            //Is it a topics bookmark?
-            Bookmark firstBookmark = topicsBookmarked.get(firstIndex);
+            if ( book.matchExists(topicsBookmarked) )
+                newTopicBookmarks.add(book);
 
-            //Swap the bookmarks.
-            topicsBookmarked.set(firstIndex, topicsBookmarked.get(secondIndex));
-            topicsBookmarked.set(secondIndex, firstBookmark);
 
-            //Update the bookmarks.
+            //Is it a board bookmark?
-            updateTopicBookmarks();
+            else if ( book.matchExists(boardsBookmarked) )
+                newBoardBookmarks.add(book);
         }
 
-        //Swap on Board Bookmarks.
-        else if ( first.matchExists(boardsBookmarked) )
-        {
-            //Find the index of the first and second bookmark.
-            int firstIndex = -1, secondIndex = -1;
-            for (int i = 0; i < boardsBookmarked.size(); i++)
-            {
-
-                //Find the first index.
-                if (first.getId().equals(boardsBookmarked.get(i).getId()))
-                    firstIndex = i;
-
-
-                //Find the second index.
-                else if (second.getId().equals(boardsBookmarked.get(i).getId()))
-                    secondIndex = i;
 
-                //If both indexes found, stop.
+        if (newTopicBookmarks.size() > 0)
-                if (firstIndex != -1 && secondIndex != -1)
+            topicsBookmarked = newTopicBookmarks;
-                    break;
-            }
-
-            if (BuildConfig.DEBUG && !(firstIndex != -1 && secondIndex != -1)) {
-                throw new AssertionError("firstIndex and secondIndex must exist!");
-            }
-
-            //Temp store the first bookmark.
-            Bookmark firstBookmark = boardsBookmarked.get(firstIndex);
 
-            //Swap the bookmarks.
+        if (newBoardBookmarks.size() > 0)
-            boardsBookmarked.set(firstIndex, boardsBookmarked.get(secondIndex));
+            boardsBookmarked = newBoardBookmarks;
-            boardsBookmarked.set(secondIndex, firstBookmark);
 
-            //Update the bookmarks.
+        //Update the bookmarks.
-            updateBoardBookmarks();
+        updateTopicBookmarks();
-        }
+        updateBoardBookmarks();
     }
 //-------------------------------------------BOOKMARKS END------------------------------------------
 

app/src/main/res/drawable/bookmark_row_dashed_bg.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+<shape xmlns:android="http://schemas.android.com/apk/res/android">
+    <solid android:color="@color/background"/>
+    <stroke
+        android:width="2dp"
+        android:color="#B1BCBE"
+        android:dashWidth="10px"
+        android:dashGap="10px"
+        />
+    <corners android:radius="10dp"/>
+    <padding android:left="8dp" android:top="8dp" android:right="8dp" android:bottom="8dp" />
+</shape>