Grid merging footer cells

Change-Id: I24895c7ae602ffc9a7812dcc441e99ac670356e2

6 files changed, 217 insertions, 59 deletions

diff --git a/client/src/main/java/com/vaadin/client/connectors/grid/GridConnector.java b/client/src/main/java/com/vaadin/client/connectors/grid/GridConnector.java
index 617a0480ba..bcae476cf3 100644
--- a/client/src/main/java/com/vaadin/client/connectors/grid/GridConnector.java
+++ b/client/src/main/java/com/vaadin/client/connectors/grid/GridConnector.java
@@ -232,22 +232,26 @@ public class GridConnector extends AbstractListingConnector
                 grid.setDefaultHeaderRow(row);
             }
 
-            rowState.cells.forEach((columnId, cellState) -> {
-                updateHeaderCellFromState(row.getCell(getColumn(columnId)),
-                        cellState);
-            });
-            for (Map.Entry<CellState, Set<String>> cellGroupEntry : rowState.cellGroups.entrySet()) {
-                Set<String> group = cellGroupEntry.getValue();
-
-                Grid.Column<?, ?>[] columns =
-                        group.stream().map(idToColumn::get).toArray(size->new Grid.Column<?, ?>[size]);
-                // Set state to be the same as first in group.
-                updateHeaderCellFromState(row.join(columns), cellGroupEntry.getKey());
-            }
+            updateStaticRow(rowState, row);
+        }
+    }
+
+    private void updateStaticRow(RowState rowState, Grid.StaticSection.StaticRow row) {
+        rowState.cells.forEach((columnId, cellState) -> {
+            updateStaticCellFromState(row.getCell(getColumn(columnId)),
+                    cellState);
+        });
+        for (Map.Entry<CellState, Set<String>> cellGroupEntry : rowState.cellGroups.entrySet()) {
+            Set<String> group = cellGroupEntry.getValue();
+
+            Grid.Column<?, ?>[] columns =
+                    group.stream().map(idToColumn::get).toArray(size->new Grid.Column<?, ?>[size]);
+            // Set state to be the same as first in group.
+            updateStaticCellFromState(row.join(columns), cellGroupEntry.getKey());
         }
     }
 
-    private void updateHeaderCellFromState(HeaderCell cell,
+    private void updateStaticCellFromState(Grid.StaticSection.StaticCell cell,
             CellState cellState) {
         switch (cellState.type) {
         case TEXT:
@@ -288,39 +292,10 @@ public class GridConnector extends AbstractListingConnector
         for (RowState rowState : state.rows) {
             FooterRow row = grid.appendFooterRow();
 
-            rowState.cells.forEach((columnId, cellState) -> {
-                updateFooterCellFromState(row.getCell(getColumn(columnId)),
-                        cellState);
-            });
+            updateStaticRow(rowState, row);
         }
     }
 
-    private void updateFooterCellFromState(FooterCell cell,
-            CellState cellState) {
-        switch (cellState.type) {
-        case TEXT:
-            cell.setText(cellState.text);
-            break;
-        case HTML:
-            cell.setHtml(cellState.html);
-            break;
-        case WIDGET:
-            ComponentConnector connector = (ComponentConnector) cellState.connector;
-            if (connector != null) {
-                cell.setWidget(connector.getWidget());
-            } else {
-                // This happens if you do setVisible(false) on the component on
-                // the server side
-                cell.setWidget(null);
-            }
-            break;
-        default:
-            throw new IllegalStateException(
-                    "unexpected cell type: " + cellState.type);
-        }
-        cell.setStyleName(cellState.styleName);
-    }
-
     @Override
     public void setDataSource(DataSource<JsonObject> dataSource) {
         super.setDataSource(dataSource);
diff --git a/server/src/main/java/com/vaadin/ui/Grid.java b/server/src/main/java/com/vaadin/ui/Grid.java
index 5010387377..7e38e7028d 100644
--- a/server/src/main/java/com/vaadin/ui/Grid.java
+++ b/server/src/main/java/com/vaadin/ui/Grid.java
@@ -1672,20 +1672,30 @@ public class Grid<T> extends AbstractListing<T>
         }
 
         /**
-         * Merges columns cells in a row
+         * Merges column cells in the row. Original cells are hidden, and new merged cell is shown instead.
+         * The cell has a width of all merged cells together, inherits styles of the first merged cell
+         * but has empty caption.
          *
-         * @param cells
-         *            The cells to merge. Must be from the same row.
-         * @return The remaining visible cell after the merge
+         * @param cellsToMerge
+         *            the cells which should be merged. The cells should not be merged to any other cell set.
+         * @return the remaining visible cell after the merge
+         *
+         *  @see #join(Grid.HeaderCell...)
+         * @see com.vaadin.ui.AbstractComponent#setCaption(String) setCaption
          */
         HeaderCell join(Set<HeaderCell> cellsToMerge);
 
         /**
-         * Merges columns cells in a row
+         * Merges column cells in the row. Original cells are hidden, and new merged cell is shown instead.
+         * The cell has a width of all merged cells together, inherits styles of the first merged cell
+         * but has empty caption.
+         *
+         * @param cellsToMerge
+         *            the cells which should be merged. The cells should not be merged to any other cell set.
+         * @return the remaining visible cell after the merge
          *
-         * @param cells
-         *            The cells to merge. Must be from the same row.
-         * @return The remaining visible cell after the merge
+         *  @see #join(Set)
+         * @see com.vaadin.ui.AbstractComponent#setCaption(String) setCaption
          */
         HeaderCell join(HeaderCell... cellsToMerge);
 
@@ -1785,6 +1795,34 @@ public class Grid<T> extends AbstractListing<T>
         public default FooterCell getCell(Column<?, ?> column) {
             return getCell(column.getId());
         }
+
+        /**
+         * Merges column cells in the row. Original cells are hidden, and new merged cell is shown instead.
+         * The cell has a width of all merged cells together, inherits styles of the first merged cell
+         * but has empty caption.
+         *
+         * @param cellsToMerge
+         *            the cells which should be merged. The cells should not be merged to any other cell set.
+         * @return the remaining visible cell after the merge
+         *
+         * @see #join(Grid.FooterCell...)
+         * @see com.vaadin.ui.AbstractComponent#setCaption(String) setCaption
+         */
+        FooterCell join(Set<FooterCell> cellsToMerge);
+
+        /**
+         * Merges column cells in the row. Original cells are hidden, and new merged cell is shown instead.
+         * The cell has a width of all merged cells together, inherits styles of the first merged cell
+         * but has empty caption.
+         *
+         * @param cellsToMerge
+         *            the cells which should be merged. The cells should not be merged to any other cell set.
+         * @return the remaining visible cell after the merge
+         *
+         * @see #join(Set)
+         * @see com.vaadin.ui.AbstractComponent#setCaption(String) setCaption
+         */
+        FooterCell join(FooterCell ... cellsToMerge);
     }
 
     /**
@@ -1844,6 +1882,13 @@ public class Grid<T> extends AbstractListing<T>
          * @return cell content type
          */
         public GridStaticCellType getCellType();
+
+        /**
+         * Gets the column id where this cell is.
+         *
+         * @return column id for this cell
+         */
+        public String getColumnId();
     }
 
     /**
diff --git a/server/src/main/java/com/vaadin/ui/components/grid/Footer.java b/server/src/main/java/com/vaadin/ui/components/grid/Footer.java
index 9423e2d842..0da179a2c0 100644
--- a/server/src/main/java/com/vaadin/ui/components/grid/Footer.java
+++ b/server/src/main/java/com/vaadin/ui/components/grid/Footer.java
@@ -17,6 +17,10 @@ package com.vaadin.ui.components.grid;
 
 import com.vaadin.ui.Grid;
 
+import java.util.Arrays;
+import java.util.HashSet;
+import java.util.Set;
+
 /**
  * Represents the footer section of a Grid.
  *
@@ -61,6 +65,56 @@ public abstract class Footer extends StaticSection<Footer.Row> {
         protected String getCellTagName() {
             return "td";
         }
+
+        /**
+         * Merges column cells in the row. Original cells are hidden, and new merged cell is shown instead.
+         * The cell has a width of all merged cells together, inherits styles of the first merged cell
+         * but has empty caption.
+         *
+         * @param cellsToMerge
+         *            the cells which should be merged. The cells should not be merged to any other cell set.
+         * @return the remaining visible cell after the merge
+         *
+         * @see #join(Grid.FooterCell...)
+         * @see com.vaadin.ui.AbstractComponent#setCaption(String) setCaption
+         */
+        @Override
+        public Grid.FooterCell join(Set<Grid.FooterCell> cellsToMerge) {
+            for (Grid.FooterCell cell : cellsToMerge) {
+                checkIfAlreadyMerged(cell.getColumnId());
+            }
+
+            // Create new cell data for the group
+            Cell newCell = createCell();
+
+            Set<String> columnGroup = new HashSet<>();
+            for (Grid.FooterCell cell : cellsToMerge) {
+                columnGroup.add(cell.getColumnId());
+            }
+            addMergedCell(newCell, columnGroup);
+            markAsDirty();
+            return newCell;
+        }
+
+        /**
+         * Merges column cells in the row. Original cells are hidden, and new merged cell is shown instead.
+         * The cell has a width of all merged cells together, inherits styles of the first merged cell
+         * but has empty caption.
+         *
+         * @param cellsToMerge
+         *            the cells which should be merged. The cells should not be merged to any other cell set.
+         * @return the remaining visible cell after the merge
+         *
+         * @see #join(Set)
+         * @see com.vaadin.ui.AbstractComponent#setCaption(String) setCaption
+         */
+        @Override
+        public Grid.FooterCell join(Grid.FooterCell... cellsToMerge) {
+            Set<Grid.FooterCell> footerCells = new HashSet<>(Arrays.asList(cellsToMerge));
+            return join(footerCells);
+        }
+
+
     }
 
     @Override
diff --git a/server/src/main/java/com/vaadin/ui/components/grid/Header.java b/server/src/main/java/com/vaadin/ui/components/grid/Header.java
index 6a4b72c5f9..5236a200fa 100644
--- a/server/src/main/java/com/vaadin/ui/components/grid/Header.java
+++ b/server/src/main/java/com/vaadin/ui/components/grid/Header.java
@@ -87,11 +87,16 @@ public abstract class Header extends StaticSection<Header.Row> {
         }
 
         /**
-         * Merges columns cells in a row
+         * Merges column cells in the row. Original cells are hidden, and new merged cell is shown instead.
+         * The cell has a width of all merged cells together, inherits styles of the first merged cell
+         * but has empty caption.
          *
          * @param cellsToMerge
-         *            the cells which should be merged
+         *            the cells which should be merged. The cells should not be merged to any other cell set.
          * @return the remaining visible cell after the merge
+         *
+         * @see #join(Grid.HeaderCell...)
+         * @see com.vaadin.ui.AbstractComponent#setCaption(String) setCaption
          */
         @Override
         public Grid.HeaderCell join(Set<Grid.HeaderCell> cellsToMerge) {
@@ -112,11 +117,16 @@ public abstract class Header extends StaticSection<Header.Row> {
         }
 
         /**
-         * Merges columns cells in a row
+         * Merges column cells in the row. Original cells are hidden, and new merged cell is shown instead.
+         * The cell has a width of all merged cells together, inherits styles of the first merged cell
+         * but has empty caption.
          *
          * @param cellsToMerge
-         *            the cells which should be merged
+         *            the cells which should be merged. The cells should not be merged to any other cell set.
          * @return the remaining visible cell after the merge
+         *
+         * @see #join(Set)
+         * @see com.vaadin.ui.AbstractComponent#setCaption(String) setCaption
          */
         @Override
         public Grid.HeaderCell join(Grid.HeaderCell... cellsToMerge) {
diff --git a/uitest/src/main/java/com/vaadin/tests/components/grid/basics/GridBasics.java b/uitest/src/main/java/com/vaadin/tests/components/grid/basics/GridBasics.java
index 4f36eb6207..a39ff27e88 100644
--- a/uitest/src/main/java/com/vaadin/tests/components/grid/basics/GridBasics.java
+++ b/uitest/src/main/java/com/vaadin/tests/components/grid/basics/GridBasics.java
@@ -547,6 +547,16 @@ public class GridBasics extends AbstractTestUIWithLog {
         headerRow.join(toMerge).setText(jointCellText);
     }
 
+    private void mergeFooterСells(int rowIndex, String jointCellText, int... columnIndexes) {
+        FooterRow footerRow = grid.getFooterRow(rowIndex);
+        List<Column<DataObject, ?>> columns = grid.getColumns();
+        Set<Grid.FooterCell> toMerge = new HashSet<>();
+        for (int columnIndex : columnIndexes) {
+            toMerge.add(footerRow.getCell(columns.get(columnIndex)));
+        }
+        footerRow.join(toMerge).setText(jointCellText);
+    }
+
     private void createFooterMenu(MenuItem footerMenu) {
         footerMenu.addItem("Add default footer row", menuItem -> {
             FooterRow defaultFooter = grid.appendFooterRow();
@@ -574,6 +584,15 @@ public class GridBasics extends AbstractTestUIWithLog {
         footerMenu.addItem("Remove first footer row", menuItem -> {
             grid.removeFooterRow(0);
         });
+        footerMenu.addItem("Merge Footer Cells [0,0..1]", menuItem -> {
+            mergeFooterСells(0, "0+1", 0, 1);
+        });
+        footerMenu.addItem("Merge Footer Cells [1,1..3]", menuItem -> {
+            mergeFooterСells(1, "1+2+3", 1, 2, 3);
+        });
+        footerMenu.addItem("Merge Footer Cells [0,6..7]", menuItem -> {
+            mergeFooterСells(0, "6+7", 6, 7);
+        });
     }
 
     /* DetailsGenerator related things */
diff --git a/uitest/src/test/java/com/vaadin/tests/components/grid/basics/GridHeaderFooterTest.java b/uitest/src/test/java/com/vaadin/tests/components/grid/basics/GridHeaderFooterTest.java
index 94f30fe279..5e2b0eb9f7 100644
--- a/uitest/src/test/java/com/vaadin/tests/components/grid/basics/GridHeaderFooterTest.java
+++ b/uitest/src/test/java/com/vaadin/tests/components/grid/basics/GridHeaderFooterTest.java
@@ -265,16 +265,25 @@ public class GridHeaderFooterTest extends GridBasicsTest {
         selectMenuPath("Component", "Header", "Append header row");
         selectMenuPath("Component", "Header", "Merge Header Cells [0,0..1]");
 
-        GridCellElement c00 = getGridElement().getHeaderCell(0, 0);
-        assertEquals("0+1", c00.getText());
-        assertEquals("Colspan of cell [0,0]", "2", c00.getAttribute("colspan"));
+        selectMenuPath("Component", "Footer", "Append footer row");
+        selectMenuPath("Component", "Footer", "Merge Footer Cells [0,0..1]");
+
+        checkMergedHeaderFooter();
 
         selectMenuPath("Component", "Columns", "Column 1", "Remove");
         selectMenuPath("Component", "Header", "Append header row");
+        selectMenuPath("Component", "Footer", "Append footer row");
+
+        checkHeaderAfterDelete();
+        checkFooterAfterDelete();
+
+    }
 
+    private void checkHeaderAfterDelete() {
+        GridCellElement c00;
         c00 = getGridElement().getHeaderCell(0, 0);
         assertEquals("Column 0", c00.getText());
-        assertEquals("Colspan of cell [0,0]", "1", c00.getAttribute("colspan"));
+        assertEquals("Colspan of header cell [0,0]", "1", c00.getAttribute("colspan"));
 
         GridCellElement c01 = getGridElement().getHeaderCell(0, 1);
         assertEquals("Column 2", c01.getText());
@@ -290,8 +299,33 @@ public class GridHeaderFooterTest extends GridBasicsTest {
 
         GridCellElement c21 = getGridElement().getHeaderCell(2, 1);
         assertEquals("Header cell 1", c21.getText());
+    }
+
+    private void checkFooterAfterDelete() {
+        GridCellElement c10;
+        //footer has an invisible first row
+        c10 = getGridElement().getFooterCell(1, 0);
+        assertEquals("Footer cell 0", c10.getText());
+        assertEquals("Colspan of footer cell [0,0]", "1", c10.getAttribute("colspan"));
 
+        GridCellElement c11 = getGridElement().getFooterCell(1, 1);
+        assertEquals("Footer cell 2", c11.getText());
 
+        GridCellElement c20 = getGridElement().getFooterCell(2, 0);
+        assertEquals("Footer cell 0", c20.getText());
+
+        GridCellElement c21 = getGridElement().getFooterCell(2, 1);
+        assertEquals("Footer cell 1", c21.getText());
+    }
+
+    private void checkMergedHeaderFooter() {
+        GridCellElement c00 = getGridElement().getHeaderCell(0, 0);
+        assertEquals("0+1", c00.getText());
+        assertEquals("Colspan of header cell [0,0]", "2", c00.getAttribute("colspan"));
+
+        c00 = getGridElement().getFooterCell(0, 0);
+        assertEquals("0+1", c00.getText());
+        assertEquals("Colspan of footer cell [0,0]", "2", c00.getAttribute("colspan"));
     }
 
     @Test
@@ -315,6 +349,27 @@ public class GridHeaderFooterTest extends GridBasicsTest {
 
     }
 
+    @Test
+    public void testFooterMerge() {
+        selectMenuPath("Component", "Footer", "Append footer row");
+        selectMenuPath("Component", "Footer", "Merge Footer Cells [0,0..1]");
+        selectMenuPath("Component", "Footer", "Merge Footer Cells [1,1..3]");
+        selectMenuPath("Component", "Footer", "Merge Footer Cells [0,6..7]");
+
+        GridCellElement mergedCell1 = getGridElement().getFooterCell(0, 0);
+        assertEquals("0+1", mergedCell1.getText());
+        assertEquals("Colspan, cell [0,0]", "2", mergedCell1.getAttribute("colspan"));
+
+        GridCellElement mergedCell2 = getGridElement().getFooterCell(1, 1);
+        assertEquals("1+2+3", mergedCell2.getText());
+        assertEquals("Colspan of cell [1,1]", "3", mergedCell2.getAttribute("colspan"));
+
+        GridCellElement mergedCell3 = getGridElement().getFooterCell(0, 6);
+        assertEquals("6+7", mergedCell3.getText());
+        assertEquals("Colspan of cell [0,6]", "2", mergedCell3.getAttribute("colspan"));
+
+    }
+
     private void toggleColumnHidable(int index) {
         selectMenuPath("Component", "Columns", "Column " + index, "Hidable");
     }