Dev2.CustomControls.SimpleGridSplitter.ResizeRows C# (CSharp) Method

        private void ResizeRows(double delta)
        {
            //if no change just return
            if (delta.CompareTo(0D) == 0) return;

            //Only works when the grid has at least 3 rows
            int containingGridRows = _containingGrid.RowDefinitions.Count;
            if (containingGridRows < 3) return;

            int row = Grid.GetRow(this);

            if (row < 1) return; //Do nothing if in top row - introduce ResizeBehavior
            if (row == containingGridRows - 1) return; //Do nothing if in last row - introduce ResizeBehavior

            int upperRow = row - 1;
            int lowerRow = row + 1;

            bool isUpperContentMaxed;
            bool isLowerContentMaxed;

            ScrollViewer upperScrollViewer = GetScrollViewer(_containingGrid, upperRow);
            ScrollViewer lowerScrollViewer = GetScrollViewer(_containingGrid, lowerRow);

            if (upperScrollViewer != null)
                isUpperContentMaxed = upperScrollViewer.ExtentHeight.CompareTo(upperScrollViewer.ViewportHeight) == 0;
            else
            {
                ScrollBar upperScrollBar = GetScrollBar(_containingGrid, upperRow);
                isUpperContentMaxed = upperScrollBar.Visibility == Visibility.Collapsed;
            }

            if (lowerScrollViewer != null)
                isLowerContentMaxed = lowerScrollViewer.ExtentHeight.CompareTo(lowerScrollViewer.ViewportHeight) == 0;
            else
            {
                ScrollBar lowerScrollBar = GetScrollBar(_containingGrid, lowerRow);
                isLowerContentMaxed = lowerScrollBar.Visibility == Visibility.Collapsed;
            }

            if (delta < 0 && isLowerContentMaxed) return;
            if (delta > 0 && isUpperContentMaxed) return;

            RowDefinition upperRowDefinition = _containingGrid.RowDefinitions[upperRow];
            RowDefinition lowerRowDefinition = _containingGrid.RowDefinitions[lowerRow];

            double upperRowActualHeight = upperRowDefinition.ActualHeight;
            double lowerRowActualHeight = lowerRowDefinition.ActualHeight;

            double upperRowMaxHeight = upperRowDefinition.MaxHeight;
            double lowerRowMaxHeight = lowerRowDefinition.MaxHeight;
            double upperRowMinHeight = upperRowDefinition.MinHeight;
            double lowerRowMinHeight = lowerRowDefinition.MinHeight;

            delta = AdjustDelta(upperRowActualHeight, upperRowMinHeight, upperRowMaxHeight, 1, delta);
            delta = AdjustDelta(lowerRowActualHeight, lowerRowMinHeight, lowerRowMaxHeight, -1, delta);

            double newUpperRowActualHeight = upperRowActualHeight + delta;
            double newLowerRowActualHeight = lowerRowActualHeight - delta;
            double requestedActualHeight = newUpperRowActualHeight + newLowerRowActualHeight;

            _containingGrid.BeginInit();

            double upperRatio = newUpperRowActualHeight/requestedActualHeight;
            double lowerRatio = newLowerRowActualHeight/requestedActualHeight;
            upperRowDefinition.Height = new GridLength(upperRatio, GridUnitType.Star);
            lowerRowDefinition.Height = new GridLength(lowerRatio, GridUnitType.Star);

            _containingGrid.EndInit();
        }