Added support to be able to insert a new column at a specific index

README.md

@@ -19,7 +19,7 @@ YouTube demo video<br>
     }
 
     dependencies {
-        compile 'com.github.woxthebox:draglistview:1.6.0'
+        compile 'com.github.woxthebox:draglistview:1.6.1'
     }
 
 Add this to proguard rules, otherwise animations won't work correctly
@@ -216,14 +216,14 @@ List and Grid layouts are used as example in the sample project.
             }
         });
         ...
-        mBoardView.addColumnList(listAdapter, header, false);
+        mBoardView.addColumn(listAdapter, header, null, false);
 
   To enable dragging and reordering of columns you need to provide a column drag view when adding the column. It is the view that will
   start the column drag process when long pressed on. You can also implement a custom column drag item to control the visuals and animations.
   Check out the sample app to see how it is done. If no custom drag item is used a screenshot of the column will be used instead.
 
     mBoardView.setCustomColumnDragItem(new MyColumnDragItem(getActivity(), R.layout.column_drag_layout));
-    mBoardView.addColumnList(listAdapter, header, columnDragView, false);
+    mBoardView.addColumn(listAdapter, header, columnDragView, false);
 
   For your adapter, extend DragItemAdapter and call setItemList() with a List<T> type. setItemList() can be called anytime later to change the list.
 

library/gradle.properties

@@ -1,5 +1,5 @@
-VERSION_NAME=1.6.0
-VERSION_CODE=47
+VERSION_NAME=1.6.1
+VERSION_CODE=48
 GROUP=com.github.woxthebox
 
 POM_DESCRIPTION=Drag and drop to re-order items in a list, grid or board.

library/src/main/java/com/woxthebox/draglistview/BoardView.java

@@ -23,6 +23,7 @@
 import android.content.res.Resources;
 import android.os.Parcel;
 import android.os.Parcelable;
+import android.support.annotation.Nullable;
 import android.support.v4.view.ViewCompat;
 import android.support.v7.widget.DefaultItemAnimator;
 import android.support.v7.widget.LinearLayoutManager;
@@ -773,16 +774,39 @@ public void onLayoutChange(View v, int left, int top, int right, int bottom, int
     }
 
     /**
-     * Adds a column to the board.
+     * Inserts a column to the board at a specific index.
      *
      * @param adapter          Adapter with the items for the column.
-     * @param header           Header view that will be positioned above the column.
-     * @param columnDragView   View that will act as handle to drag and drop columns.
+     * @param index            Index where on the board to add the column.
+     * @param header           Header view that will be positioned above the column. Can be null.
+     * @param columnDragView   View that will act as handle to drag and drop columns. Can be null.
      * @param hasFixedItemSize If the items will have a fixed or dynamic size.
+     *
      * @return The created DragItemRecyclerView.
      */
-    public DragItemRecyclerView addColumnList(final DragItemAdapter adapter, final View header, View columnDragView, boolean hasFixedItemSize) {
-        final DragItemRecyclerView recyclerView = addColumnList(adapter, header, hasFixedItemSize);
+    public DragItemRecyclerView insertColumn(final DragItemAdapter adapter, int index, final @Nullable View header, @Nullable View columnDragView, boolean hasFixedItemSize) {
+        final DragItemRecyclerView recyclerView = insertColumn(adapter, index, header, hasFixedItemSize);
+        setupColumnDragListener(columnDragView, recyclerView);
+        return recyclerView;
+    }
+
+    /**
+     * Adds a column at the last index of the board.
+     *
+     * @param adapter          Adapter with the items for the column.
+     * @param header           Header view that will be positioned above the column. Can be null.
+     * @param columnDragView   View that will act as handle to drag and drop columns. Can be null.
+     * @param hasFixedItemSize If the items will have a fixed or dynamic size.
+     *
+     * @return The created DragItemRecyclerView.
+     */
+    public DragItemRecyclerView addColumn(final DragItemAdapter adapter, final @Nullable View header, @Nullable View columnDragView, boolean hasFixedItemSize) {
+        final DragItemRecyclerView recyclerView = insertColumn(adapter, getColumnCount(), header, hasFixedItemSize);
+        setupColumnDragListener(columnDragView, recyclerView);
+        return recyclerView;
+    }
+
+    private void setupColumnDragListener(View columnDragView, final DragItemRecyclerView recyclerView ) {
         if (columnDragView != null) {
             columnDragView.setOnLongClickListener(new OnLongClickListener() {
                 @Override
@@ -792,10 +816,13 @@ public boolean onLongClick(View v) {
                 }
             });
         }
-        return recyclerView;
     }
 
-    public DragItemRecyclerView addColumnList(final DragItemAdapter adapter, final View header, boolean hasFixedItemSize) {
+    private DragItemRecyclerView insertColumn(final DragItemAdapter adapter, int index, final @Nullable View header, boolean hasFixedItemSize) {
+        if (index > getColumnCount()) {
+            throw new IllegalArgumentException("Index is out of bounds");
+        }
+
         final DragItemRecyclerView recyclerView = (DragItemRecyclerView) LayoutInflater.from(getContext()).inflate(R.layout.drag_item_recycler_view, this, false);
         recyclerView.setId(getColumnCount());
         recyclerView.setHorizontalScrollBarEnabled(false);
@@ -876,8 +903,8 @@ public boolean isDragging() {
         }
         layout.addView(recyclerView);
 
-        mLists.add(recyclerView);
-        mColumnLayout.addView(layout);
+        mLists.add(index, recyclerView);
+        mColumnLayout.addView(layout, index);
         return recyclerView;
     }
 

sample/src/main/java/com/woxthebox/draglistview/sample/BoardFragment.java

@@ -36,7 +36,6 @@
 import android.widget.LinearLayout;
 import android.widget.ScrollView;
 import android.widget.TextView;
-import android.widget.Toast;
 
 import com.woxthebox.draglistview.BoardView;
 import com.woxthebox.draglistview.DragItem;
@@ -139,11 +138,11 @@ public void onActivityCreated(@Nullable Bundle savedInstanceState) {
 
         ((AppCompatActivity) getActivity()).getSupportActionBar().setTitle("Board");
 
-        addColumnList();
-        addColumnList();
-        addColumnList();
-        addColumnList();
-        addColumnList();
+        addColumn();
+        addColumn();
+        addColumn();
+        addColumn();
+        addColumn();
     }
 
     @Override
@@ -171,7 +170,7 @@ public boolean onOptionsItemSelected(MenuItem item) {
                 getActivity().invalidateOptionsMenu();
                 return true;
             case R.id.action_add_column:
-                addColumnList();
+                addColumn();
                 return true;
             case R.id.action_remove_column:
                 mBoardView.removeColumn(0);
@@ -183,7 +182,7 @@ public boolean onOptionsItemSelected(MenuItem item) {
         return super.onOptionsItemSelected(item);
     }
 
-    private void addColumnList() {
+    private void addColumn() {
         final ArrayList<Pair<Long, String>> mItemArray = new ArrayList<>();
         int addItems = 15;
         for (int i = 0; i < addItems; i++) {
@@ -209,7 +208,7 @@ public void onClick(View v) {
                 ((TextView) header.findViewById(R.id.item_count)).setText(String.valueOf(mItemArray.size()));
             }
         });
-        mBoardView.addColumnList(listAdapter, header, header, false);
+        mBoardView.addColumn(listAdapter, header, header, false);
         mColumns++;
     }
 

sample/src/main/java/com/woxthebox/draglistview/sample/ItemAdapter.java

@@ -41,8 +41,9 @@ class ItemAdapter extends DragItemAdapter<Pair<Long, String>, ItemAdapter.ViewHo
         setItemList(list);
     }
 
+    @NonNull
     @Override
-    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
+    public ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
         View view = LayoutInflater.from(parent.getContext()).inflate(mLayoutId, parent, false);
         return new ViewHolder(view);
     }