+
+ // Helper function for Layout() that clears the space needed by a cell with rowspan > 1
+int GetRowspanDisplacement(const wxRichTextTable* table, int row, int col, int paddingX, const wxArrayInt& colWidths)
+{
+ // If one or more cells above-left of this one has rowspan > 1, the affected cells below it
+ // will have been hidden and have width 0. As a result they are ignored by the layout algorithm,
+ // and all cells to their right are effectively shifted left. As a result there's no hole for
+ // the spanning cell to fill.
+ // So search back along the current row for hidden cells. However there's also the annoying issue of a
+ // rowspanning cell that also has colspam. So we can't rely on the rowspanning cell being directly above
+ // the first hidden one we come to. We also can't rely on a cell being hidden only by one type of span;
+ // there's nothing to stop a cell being hidden by colspan, and then again hidden from above by rowspan.
+ // The answer is to look above each hidden cell in turn, which I think covers all bases.
+ int deltaX = 0;
+ for (int prevcol = 0; prevcol < col; ++prevcol)
+ {
+ if (!table->GetCell(row, prevcol)->IsShown())
+ {
+ // We've found a hidden cell. If it's hidden because of colspan to its left, it's
+ // already been taken into account; but not if there's a rowspanning cell above
+ for (int prevrow = row-1; prevrow >= 0; --prevrow)
+ {
+ wxRichTextCell* cell = table->GetCell(prevrow, prevcol);
+ if (cell && cell->IsShown())
+ {
+ int rowSpan = cell->GetRowspan();
+ if (rowSpan > 1 && rowSpan > (row-prevrow))
+ {
+ // There is a rowspanning cell above above the hidden one, so we need
+ // to right-shift the index cell by this column's width. Furthermore,
+ // if the cell also colspans, we need to shift by all affected columns
+ for (int colSpan = 0; colSpan < cell->GetColspan(); ++colSpan)
+ deltaX += (colWidths[prevcol+colSpan] + paddingX);
+ break;
+ }
+ }
+ }
+ }
+ }
+ return deltaX;
+}
+
+ // Helper function for Layout() that expands any cell with rowspan > 1
+void ExpandCellsWithRowspan(const wxRichTextTable* table, int paddingY, int& bottomY, wxDC& dc, wxRichTextDrawingContext& context, const wxRect& availableSpace, int style)
+{
+ // This is called when the table's cell layout is otherwise complete.
+ // For any cell with rowspan > 1, expand downwards into the row(s) below.
+
+ // Start by finding the current 'y' of the top of each row, plus the bottom of the available area for cells.
+ // Deduce this from the top of a visible cell in the row below. (If none are visible, the row will be invisible anyway and can be ignored.)
+ const int rowCount = table->GetRowCount();
+ const int colCount = table->GetColumnCount();
+ wxArrayInt rowTops;
+ rowTops.Add(0, rowCount+1);
+ int row;
+ for (row = 0; row < rowCount; ++row)
+ {
+ for (int column = 0; column < colCount; ++column)
+ {
+ wxRichTextCell* cell = table->GetCell(row, column);
+ if (cell && cell->IsShown())
+ {
+ rowTops[row] = cell->GetPosition().y;
+ break;
+ }
+ }
+ }
+ rowTops[rowCount] = bottomY + paddingY; // The table bottom, which was passed to us
+
+ bool needsRelay = false;
+
+ for (row = 0; row < rowCount-1; ++row) // -1 as the bottom row can't rowspan
+ {
+ for (int col = 0; col < colCount; ++col)
+ {
+ wxRichTextCell* cell = table->GetCell(row, col);
+ if (cell && cell->IsShown())
+ {
+ int span = cell->GetRowspan();
+ if (span > 1)
+ {
+ span = wxMin(span, rowCount-row); // Don't try to span below the table!
+ if (span < 2)
+ continue;
+
+ int availableHeight = rowTops[row+span] - rowTops[row] - paddingY;
+ wxSize newSize = wxSize(cell->GetCachedSize().GetWidth(), availableHeight);
+ wxRect availableCellSpace = wxRect(cell->GetPosition(), newSize);
+ cell->Invalidate(wxRICHTEXT_ALL);
+ cell->Layout(dc, context, availableCellSpace, availableSpace, style);
+ // Ensure there's room in the span to display its contents, else it'll overwrite lower rows
+ int overhang = cell->GetCachedSize().GetHeight() - availableHeight;
+ cell->SetCachedSize(newSize);
+
+ if (overhang > 0)
+ {
+ // There are 3 things to get right:
+ // 1) The easiest is the rows below the span: they need to be downshifted by the overhang, and so does the table bottom itself
+ // 2) The rows within the span, including the one holding this cell, need to be deepened by their share of the overhang
+ // e.g. if rowspan == 3, each row should increase in depth by 1/3rd of the overhang.
+ // 3) The cell with the rowspan shouldn't be touched in 2); its height will be set to the whole span later.
+ int deltaY = overhang / span;
+ int spare = overhang % span;
+
+ // Each row in the span needs to by deepened by its share of the overhang (give the first row any spare).
+ // This is achieved by increasing the value stored in the following row's rowTops
+ for (int spannedRows = 0; spannedRows < span; ++spannedRows)
+ {
+ rowTops[row+spannedRows+1] += ((deltaY * (spannedRows+1)) + (spannedRows == 0 ? spare:0));
+ }
+
+ // Any rows below the span need shifting down
+ for (int rowsBelow = row + span+1; rowsBelow <= rowCount; ++rowsBelow)
+ {
+ rowTops[rowsBelow] += overhang;
+ }
+
+ needsRelay = true;
+ }
+ }
+ }
+ }
+ }
+
+ if (!needsRelay)
+ return;
+
+ // There were overflowing rowspanning cells, so layout yet again to make the increased row depths show
+ for (row = 0; row < rowCount; ++row)
+ {
+ for (int col = 0; col < colCount; ++col)
+ {
+ wxRichTextCell* cell = table->GetCell(row, col);
+ if (cell && cell->IsShown())
+ {
+ wxPoint position(cell->GetPosition().x, rowTops[row]);
+
+ // GetRowspan() will usually return 1, but may be greater
+ wxSize size(cell->GetCachedSize().GetWidth(), rowTops[row + cell->GetRowspan()] - rowTops[row] - paddingY);
+
+ wxRect availableCellSpace = wxRect(position, size);
+ cell->Invalidate(wxRICHTEXT_ALL);
+ cell->Layout(dc, context, availableCellSpace, availableSpace, style);
+ cell->SetCachedSize(size);
+ }
+ }
+
+ bottomY = rowTops[rowCount] - paddingY;
+ }
+}
+