small improvements

MFlisar · Mar 4, 2017 · 82a3145 · 82a3145
1 parent 5a4965d
commit 82a3145
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Showing 2 changed files with 55 additions and 14 deletions.
diff --git a/demo/src/main/java/com/michaelflisar/dragselectrecyclerview/demo/MainActivity.java b/demo/src/main/java/com/michaelflisar/dragselectrecyclerview/demo/MainActivity.java
@@ -68,7 +68,12 @@ public HashSet<Integer> getSelection() {
             }
 
             @Override
-            public void updateSelection(int start, int end, boolean isSelected) {
+            public boolean isSelected(int index) {
+                return mAdapter.getSelection().contains(index);
+            }
+
+            @Override
+            public void updateSelection(int start, int end, boolean isSelected, boolean calledFromOnStart) {
                 mAdapter.selectRange(start, end, isSelected);
             }
         })

diff --git a/library/src/main/java/com/michaelflisar/dragselectrecyclerview/DragSelectionProcessor.java b/library/src/main/java/com/michaelflisar/dragselectrecyclerview/DragSelectionProcessor.java
@@ -37,6 +37,7 @@ public enum Mode
     private ISelectionStartFinishedListener mStartFinishedListener;
     private HashSet<Integer> mOriginalSelection;
     private boolean mFirstWasSelected;
+    private boolean mCheckSelectionState = false;
 
     /**
      * @param selectionHandler the handler that takes care to handle the selection events
@@ -57,7 +58,7 @@ public DragSelectionProcessor withMode(Mode mode)
         mMode = mode;
         return this;
     }
-    
+
     /**
      * @param startFinishedListener a listener that get's notified when the drag selection is started or finished
      * @return this
@@ -68,6 +69,17 @@ public DragSelectionProcessor withStartFinishedListener(ISelectionStartFinishedL
         return this;
     }
 
+    /**
+     * If this is enabled, the processor will check if an items selection state is toggled before notifying the {@link ISelectionHandler}
+     * @param check true, if this check should be enabled
+     * @return this
+     */
+    public DragSelectionProcessor withCheckSelectionState(boolean check)
+    {
+        mCheckSelectionState = check;
+        return this;
+    }
+
     @Override
     public void onSelectionStarted(int start)
     {
@@ -81,22 +93,22 @@ public void onSelectionStarted(int start)
         {
             case Simple:
             {
-                mSelectionHandler.updateSelection(start, start, true);
+                mSelectionHandler.updateSelection(start, start, true, true);
                 break;
             }
             case ToggleAndUndo:
             {
-                mSelectionHandler.updateSelection(start, start, !mOriginalSelection.contains(start));
+                mSelectionHandler.updateSelection(start, start, !mOriginalSelection.contains(start), true);
                 break;
             }
             case FirstItemDependent:
             {
-                mSelectionHandler.updateSelection(start, start, !mFirstWasSelected);
+                mSelectionHandler.updateSelection(start, start, !mFirstWasSelected, true);
                 break;
             }
             case FirstItemDependentToggleAndUndo:
             {
-                mSelectionHandler.updateSelection(start, start, !mFirstWasSelected);
+                mSelectionHandler.updateSelection(start, start, !mFirstWasSelected, true);
                 break;
             }
         }
@@ -120,45 +132,69 @@ public void onSelectChange(int start, int end, boolean isSelected)
         {
             case Simple:
             {
-                mSelectionHandler.updateSelection(start, end, isSelected);
+                if (mCheckSelectionState)
+                    checkedUpdateSelection(start, end, isSelected);
+                else
+                    mSelectionHandler.updateSelection(start, end, isSelected, false);
                 break;
             }
             case ToggleAndUndo:
             {
                 for (int i = start; i <= end; i++)
-                    mSelectionHandler.updateSelection(i, i, isSelected ? !mOriginalSelection.contains(i) :  mOriginalSelection.contains(i));
+                    checkedUpdateSelection(i, i, isSelected ? !mOriginalSelection.contains(i) :  mOriginalSelection.contains(i));
                 break;
             }
             case FirstItemDependent:
             {
-                for (int i = start; i <= end; i++)
-                    mSelectionHandler.updateSelection(i, i, isSelected ? !mFirstWasSelected :  mFirstWasSelected);
+                checkedUpdateSelection(start, end, isSelected ? !mFirstWasSelected :  mFirstWasSelected);
                 break;
             }
             case FirstItemDependentToggleAndUndo:
             {
                 for (int i = start; i <= end; i++)
-                    mSelectionHandler.updateSelection(i, i, isSelected ? !mFirstWasSelected :  mOriginalSelection.contains(i));
+                    checkedUpdateSelection(i, i, isSelected ? !mFirstWasSelected :  mOriginalSelection.contains(i));
                 break;
             }
         }
     }
 
+    private void checkedUpdateSelection(int start, int end, boolean newSelectionState)
+    {
+        if (mCheckSelectionState)
+        {
+            for (int i = start; i <= end; i++)
+            {
+                if (mSelectionHandler.isSelected(i) != newSelectionState)
+                    mSelectionHandler.updateSelection(i, i, newSelectionState, false);
+            }
+        }
+        else
+            mSelectionHandler.updateSelection(start, end, newSelectionState, false);
+    }
+
     public interface ISelectionHandler
     {
         /**
-         * Return the currently selected items => can be ignored for {@link Mode#Simple} and {@link Mode#FirstItemDependent}
+         * @return the currently selected items => can be ignored for {@link Mode#Simple} and {@link Mode#FirstItemDependent}
          */
         Set<Integer> getSelection();
 
         /**
-        * update your adapter and select select/unselect the passed index range, you be get a single for all modes but {@link Mode#Simple}
+         * only used, if {@link DragSelectionProcessor#withCheckSelectionState(boolean)} was enabled
+         * @param index the index which selection state wants to be known
+         * @return the current selection state of the passed in index
+         */
+        boolean isSelected(int index);
+
+        /**
+        * update your adapter and select select/unselect the passed index range, you be get a single for all modes but {@link Mode#Simple} and {@link Mode#FirstItemDependent}
         *
         * @param start      the first item of the range who's selection state changed
         * @param end         the last item of the range who's selection state changed
         * @param isSelected      true, if the range should be selected, false otherwise
+        * @param calledFromOnStart true, if it was called from the {@link DragSelectionProcessor#onSelectionStarted(int)} event
         */
-        void updateSelection(int start, int end, boolean isSelected);
+        void updateSelection(int start, int end, boolean isSelected, boolean calledFromOnStart);
     }
 
     public interface ISelectionStartFinishedListener