QTextDocument: allow css-styling of table cell borders

This allows to set the width, style and color of each table cell's edge
(left, right, top, bottom).

Setting the table's border-collapse mode will disable explicit cell
spacing. The basic CSS border collision rules are applied (wider border
wins, vertical over horizontal).

Setting the table's border width to a value >= 1 and enabling
borderCollapse will now draw a simple and clean table grid (1px) with an
outer border of the specified width and color.

[ChangeLog][QtGui][QTextDocument] Added CSS style table cell border
formatting with border-collapse mode.

Change-Id: I324d82284802df4c88c13c5b902fec1f4768b67e
Fixes: QTBUG-36152
Reviewed-by: Shawn Rutledge <shawn.rutledge@qt.io>

src/gui/doc/src/richtext.qdoc

@@ -1175,12 +1175,75 @@
     \row    \li \c vertical-align
             \li baseline | sub | super | middle | top | bottom
             \li Vertical text alignment. For vertical alignment in text table cells only middle, top, and bottom apply.
+    \row    \li \c border-collapse
+            \li collapse | separate
+            \li Border Collapse mode for text tables. If set to collapse, cell-spacing will not be applied.
     \row    \li \c border-color
             \li <color>
-            \li Border color for text tables.
+            \li Border color for text tables and table cells.
+    \row    \li \c border-top-color
+            \li <color>
+            \li Top border color for table cells.
+    \row    \li \c border-bottom-color
+            \li <color>
+            \li Bottom border color for table cells.
+    \row    \li \c border-left-color
+            \li <color>
+            \li Left border color for table cells.
+    \row    \li \c border-right-color
+            \li <color>
+            \li Right border color for table cells.
     \row    \li \c border-style
             \li none | dotted | dashed | dot-dash | dot-dot-dash | solid | double | groove | ridge | inset | outset
-            \li Border style for text tables.
+            \li Border style for text tables and table cells.
+    \row    \li \c border-top-style
+            \li <color>
+            \li Top border style for table cells.
+    \row    \li \c border-bottom-style
+            \li <color>
+            \li Bottom border style for table cells.
+    \row    \li \c border-left-style
+            \li <color>
+            \li Left border style for table cells.
+    \row    \li \c border-right-style
+            \li <color>
+            \li Right border style for table cells.
+    \row    \li \c border-width
+            \li <width>px
+            \li Width of table or cell border
+    \row    \li \c border-top-width
+            \li <length>px
+            \li Top border width for table cells.
+    \row    \li \c border-bottom-width
+            \li <length>px
+            \li Bottom border width for table cells.
+    \row    \li \c border-left-width
+            \li <length>px
+            \li Left border width for table cells.
+    \row    \li \c border-right-width
+            \li <length>px
+            \li Right border width for table cells.
+    \row    \li \c border-top
+            \li <width>px <border-style> <border-color>
+            \li Shorthand for setting top border width, style and color
+    \row    \li \c border-bottom
+            \li <width>px <border-style> <border-color>
+            \li Shorthand for setting bottom border width, style and color
+    \row    \li \c border-left
+            \li <width>px <border-style> <border-color>
+            \li Shorthand for setting left border width, style and color
+    \row    \li \c border-right
+            \li <width>px <border-style> <border-color>
+            \li Shorthand for setting right border width, style and color
+    \row    \li \c border-top
+            \li <width>px <border-style> <border-color>
+            \li Shorthand for setting top border width, style and color
+    \row    \li \c border-bottom
+            \li <width>px <border-style> <border-color>
+            \li Shorthand for setting bottom border width, style and color
+    \row    \li \c border
+            \li <width>px <border-style> <border-color>
+            \li Shorthand for setting all four border's width, style and color
     \row    \li \c background
             \li [ <'background-color'> || <'background-image'> ]
             \li Background shorthand property

src/gui/text/qtextformat.cpp

@@ -660,6 +660,23 @@ Q_GUI_EXPORT QDataStream &operator>>(QDataStream &stream, QTextFormat &fmt)
     \value TableCellTopPadding
     \value TableCellBottomPadding
 
+    Table cell properties intended for use with \l QTextTableFormat::borderCollapse enabled
+
+    \value TableCellTopBorder
+    \value TableCellBottomBorder
+    \value TableCellLeftBorder
+    \value TableCellRightBorder
+
+    \value TableCellTopBorderStyle
+    \value TableCellBottomBorderStyle
+    \value TableCellLeftBorderStyle
+    \value TableCellRightBorderStyle
+
+    \value TableCellTopBorderBrush
+    \value TableCellBottomBorderBrush
+    \value TableCellLeftBorderBrush
+    \value TableCellRightBorderBrush
+
     Image properties
 
     \value ImageName        The filename or source of the image.
@@ -3100,6 +3117,8 @@ QTextTableFormat::QTextTableFormat(const QTextFormat &fmt)
 
     Sets the cell \a spacing for the table. This determines the distance
     between adjacent cells.
+
+    This property will be ignored if \l borderCollapse is enabled.
 */
 
 /*!
@@ -3150,6 +3169,44 @@ QTextTableFormat::QTextTableFormat(const QTextFormat &fmt)
     \sa setHeaderRowCount()
 */
 
+/*!
+    \fn void QTextTableFormat::setBorderCollapse(bool borderCollapse)
+    \since 5.14
+
+    Enabling \a borderCollapse will have the following implications:
+    \list
+    \li The borders and grid of the table will be rendered following the
+        CSS table \c border-collapse: \c collapse rules
+    \li Setting the \c border property to a minimum value of \c 1 will render a
+        one pixel solid inner table grid using the \l borderBrush property and an
+        outer border as specified
+    \li The various border style properties of \l QTextTableCellFormat can be used to
+        customize the grid and have precedence over the border and grid of the table
+    \li The \l cellSpacing property will be ignored
+    \li For print pagination:
+        \list
+        \li Columns continued on a page will not have their top cell border rendered
+        \li Repeated header rows will always have their bottom cell border rendered
+        \endlist
+    \endlist
+
+    With borderCollapse disabled, cell borders can still be styled
+    using QTextTableCellFormat but styling will be applied only within
+    the cell's frame, which is probably not very useful in practice.
+
+    \sa setBorder(), setBorderBrush(), setBorderStyle()
+    \sa QTextTableCellFormat
+*/
+
+/*!
+    \fn bool QTextTableFormat::borderCollapse() const
+    \since 5.14
+
+    Returns true if borderCollapse is enabled.
+
+    \sa setBorderCollapse()
+*/
+
 /*!
     \fn void QTextFormat::setBackground(const QBrush &brush)
 
@@ -3488,6 +3545,228 @@ QTextImageFormat::QTextImageFormat(const QTextFormat &fmt)
    \sa setLeftPadding(), setRightPadding(), setTopPadding(), setBottomPadding()
 */
 
+/*!
+   \fn void QTextTableCellFormat::setTopBorder(qreal width)
+   \since 5.14
+
+   Sets the top border \a width of the table cell.
+
+   \sa QTextTableFormat::setBorderCollapse
+*/
+
+/*!
+   \fn qreal QTextTableCellFormat::topBorder() const
+   \since 5.14
+
+   Returns the top border width of the table cell.
+*/
+
+/*!
+   \fn void QTextTableCellFormat::setBottomBorder(qreal width)
+   \since 5.14
+
+   Sets the bottom border \a width of the table cell.
+
+   \sa QTextTableFormat::setBorderCollapse
+*/
+
+/*!
+   \fn qreal QTextTableCellFormat::bottomBorder() const
+   \since 5.14
+
+   Returns the bottom border width of the table cell.
+*/
+
+/*!
+   \fn void QTextTableCellFormat::setLeftBorder(qreal width)
+   \since 5.14
+
+   Sets the left border \a width of the table cell.
+
+   \sa QTextTableFormat::setBorderCollapse
+*/
+
+/*!
+   \fn qreal QTextTableCellFormat::leftBorder() const
+   \since 5.14
+
+   Returns the left border width of the table cell.
+*/
+
+/*!
+   \fn void QTextTableCellFormat::setRightBorder(qreal width)
+   \since 5.14
+
+   Sets the right border \a width of the table cell.
+
+   \sa QTextTableFormat::setBorderCollapse
+*/
+
+/*!
+   \fn qreal QTextTableCellFormat::rightBorder() const
+   \since 5.14
+
+   Returns the right border width of the table cell.
+*/
+
+/*!
+   \fn void QTextTableCellFormat::setBorder(qreal width)
+   \since 5.14
+
+   Sets the left, right, top, and bottom border \a width of the table cell.
+
+   \sa setLeftBorder(), setRightBorder(), setTopBorder(), setBottomBorder()
+   \sa QTextTableFormat::setBorderCollapse
+*/
+
+/*!
+   \fn void QTextTableCellFormat::setTopBorderStyle(QTextFrameFormat::BorderStyle style)
+   \since 5.14
+
+   Sets the top border \a style of the table cell.
+
+   \sa QTextTableFormat::setBorderCollapse
+*/
+
+/*!
+   \fn QTextFrameFormat::BorderStyle QTextTableCellFormat::topBorderStyle() const
+   \since 5.14
+
+   Returns the top border style of the table cell.
+*/
+
+/*!
+   \fn void QTextTableCellFormat::setBottomBorderStyle(QTextFrameFormat::BorderStyle style)
+   \since 5.14
+
+   Sets the bottom border \a style of the table cell.
+
+   \sa QTextTableFormat::setBorderCollapse
+*/
+
+/*!
+   \fn QTextFrameFormat::BorderStyle QTextTableCellFormat::bottomBorderStyle() const
+   \since 5.14
+
+   Returns the bottom border style of the table cell.
+*/
+
+/*!
+   \fn void QTextTableCellFormat::setLeftBorderStyle(QTextFrameFormat::BorderStyle style)
+   \since 5.14
+
+   Sets the left border \a style of the table cell.
+
+   \sa QTextTableFormat::setBorderCollapse
+*/
+
+/*!
+   \fn QTextFrameFormat::BorderStyle QTextTableCellFormat::leftBorderStyle() const
+   \since 5.14
+
+   Returns the left border style of the table cell.
+*/
+
+/*!
+   \fn void QTextTableCellFormat::setRightBorderStyle(QTextFrameFormat::BorderStyle style)
+   \since 5.14
+
+   Sets the right border \a style of the table cell.
+
+   \sa QTextTableFormat::setBorderCollapse
+*/
+
+/*!
+   \fn QTextFrameFormat::BorderStyle QTextTableCellFormat::rightBorderStyle() const
+   \since 5.14
+
+   Returns the right border style of the table cell.
+*/
+
+/*!
+   \fn void QTextTableCellFormat::setBorderStyle(QTextFrameFormat::BorderStyle style)
+   \since 5.14
+
+   Sets the left, right, top, and bottom border \a style of the table cell.
+
+   \sa setLeftBorderStyle(), setRightBorderStyle(), setTopBorderStyle(), setBottomBorderStyle()
+   \sa QTextTableFormat::setBorderCollapse
+*/
+
+/*!
+   \fn void QTextTableCellFormat::setTopBorderBrush(const QBrush &brush)
+   \since 5.14
+
+   Sets the top border \a brush of the table cell.
+
+   \sa QTextTableFormat::setBorderCollapse
+*/
+
+/*!
+   \fn QBrush QTextTableCellFormat::topBorderBrush() const
+   \since 5.14
+
+   Returns the top border brush of the table cell.
+*/
+
+/*!
+   \fn void QTextTableCellFormat::setBottomBorderBrush(const QBrush &brush)
+   \since 5.14
+
+   Sets the bottom border \a brush of the table cell.
+
+   \sa QTextTableFormat::setBorderCollapse
+*/
+
+/*!
+   \fn QBrush QTextTableCellFormat::bottomBorderBrush() const
+   \since 5.14
+
+   Returns the bottom border brush of the table cell.
+*/
+
+/*!
+   \fn void QTextTableCellFormat::setLeftBorderBrush(const QBrush &brush)
+   \since 5.14
+
+   Sets the left border \a brush of the table cell.
+
+   \sa QTextTableFormat::setBorderCollapse
+*/
+
+/*!
+   \fn QBrush QTextTableCellFormat::leftBorderBrush() const
+   \since 5.14
+
+   Returns the left border brush of the table cell.
+*/
+
+/*!
+   \fn void QTextTableCellFormat::setRightBorderBrush(const QBrush &brush)
+   \since 5.14
+
+   Sets the right border \a brush of the table cell.
+
+   \sa QTextTableFormat::setBorderCollapse
+*/
+
+/*!
+   \fn QBrush QTextTableCellFormat::rightBorderBrush() const
+   \since 5.14
+
+   Returns the right border brush of the table cell.
+*/
+
+/*!
+   \fn void QTextTableCellFormat::setBorderBrush(const QBrush &brush)
+   \since 5.14
+
+   Sets the left, right, top, and bottom border \a brush of the table cell.
+
+   \sa setLeftBorderBrush(), setRightBorderBrush(), setTopBorderBrush(), setBottomBorderBrush()
+   \sa QTextTableFormat::setBorderCollapse
+*/
+
 /*!
     \fn bool QTextTableCellFormat::isValid() const
     \since 4.4

src/gui/text/qtextformat.h

@@ -242,6 +242,7 @@ public:
         TableCellSpacing = 0x4102,
         TableCellPadding = 0x4103,
         TableHeaderRowCount = 0x4104,
+        TableBorderCollapse = 0x4105,
 
         // table cell properties
         TableCellRowSpan = 0x4810,
@@ -252,6 +253,21 @@ public:
         TableCellLeftPadding = 0x4814,
         TableCellRightPadding = 0x4815,
 
+        TableCellTopBorder = 0x4816,
+        TableCellBottomBorder = 0x4817,
+        TableCellLeftBorder = 0x4818,
+        TableCellRightBorder = 0x4819,
+
+        TableCellTopBorderStyle = 0x481a,
+        TableCellBottomBorderStyle = 0x481b,
+        TableCellLeftBorderStyle = 0x481c,
+        TableCellRightBorderStyle = 0x481d,
+
+        TableCellTopBorderBrush = 0x481e,
+        TableCellBottomBorderBrush = 0x481f,
+        TableCellLeftBorderBrush = 0x4820,
+        TableCellRightBorderBrush = 0x4821,
+
         // image properties
         ImageName = 0x5000,
         ImageTitle = 0x5001,
@@ -966,6 +982,11 @@ public:
     inline int headerRowCount() const
     { return intProperty(TableHeaderRowCount); }
 
+    inline void setBorderCollapse(bool borderCollapse)
+    { setProperty(TableBorderCollapse, borderCollapse); }
+    inline bool borderCollapse() const
+    { return boolProperty(TableBorderCollapse); }
+
 protected:
     explicit QTextTableFormat(const QTextFormat &fmt);
     friend class QTextFormat;
@@ -1007,6 +1028,72 @@ public:
 
     inline void setPadding(qreal padding);
 
+    inline void setTopBorder(qreal width)
+    { setProperty(TableCellTopBorder, width); }
+    inline qreal topBorder() const
+    { return doubleProperty(TableCellTopBorder); }
+
+    inline void setBottomBorder(qreal width)
+    { setProperty(TableCellBottomBorder, width); }
+    inline qreal bottomBorder() const
+    { return doubleProperty(TableCellBottomBorder); }
+
+    inline void setLeftBorder(qreal width)
+    { setProperty(TableCellLeftBorder, width); }
+    inline qreal leftBorder() const
+    { return doubleProperty(TableCellLeftBorder); }
+
+    inline void setRightBorder(qreal width)
+    { setProperty(TableCellRightBorder, width); }
+    inline qreal rightBorder() const
+    { return doubleProperty(TableCellRightBorder); }
+
+    inline void setBorder(qreal width);
+
+    inline void setTopBorderStyle(QTextFrameFormat::BorderStyle style)
+    { setProperty(TableCellTopBorderStyle, style); }
+    inline QTextFrameFormat::BorderStyle topBorderStyle() const
+    { return static_cast<QTextFrameFormat::BorderStyle>(intProperty(TableCellTopBorderStyle)); }
+
+    inline void setBottomBorderStyle(QTextFrameFormat::BorderStyle style)
+    { setProperty(TableCellBottomBorderStyle, style); }
+    inline QTextFrameFormat::BorderStyle bottomBorderStyle() const
+    { return static_cast<QTextFrameFormat::BorderStyle>(intProperty(TableCellBottomBorderStyle)); }
+
+    inline void setLeftBorderStyle(QTextFrameFormat::BorderStyle style)
+    { setProperty(TableCellLeftBorderStyle, style); }
+    inline QTextFrameFormat::BorderStyle leftBorderStyle() const
+    { return static_cast<QTextFrameFormat::BorderStyle>(intProperty(TableCellLeftBorderStyle)); }
+
+    inline void setRightBorderStyle(QTextFrameFormat::BorderStyle style)
+    { setProperty(TableCellRightBorderStyle, style); }
+    inline QTextFrameFormat::BorderStyle rightBorderStyle() const
+    { return static_cast<QTextFrameFormat::BorderStyle>(intProperty(TableCellRightBorderStyle)); }
+
+    inline void setBorderStyle(QTextFrameFormat::BorderStyle style);
+
+    inline void setTopBorderBrush(const QBrush &brush)
+    { setProperty(TableCellTopBorderBrush, brush); }
+    inline QBrush topBorderBrush() const
+    { return brushProperty(TableCellTopBorderBrush); }
+
+    inline void setBottomBorderBrush(const QBrush &brush)
+    { setProperty(TableCellBottomBorderBrush, brush); }
+    inline QBrush bottomBorderBrush() const
+    { return brushProperty(TableCellBottomBorderBrush); }
+
+    inline void setLeftBorderBrush(const QBrush &brush)
+    { setProperty(TableCellLeftBorderBrush, brush); }
+    inline QBrush leftBorderBrush() const
+    { return brushProperty(TableCellLeftBorderBrush); }
+
+    inline void setRightBorderBrush(const QBrush &brush)
+    { setProperty(TableCellRightBorderBrush, brush); }
+    inline QBrush rightBorderBrush() const
+    { return brushProperty(TableCellRightBorderBrush); }
+
+    inline void setBorderBrush(const QBrush &brush);
+
 protected:
     explicit QTextTableCellFormat(const QTextFormat &fmt);
     friend class QTextFormat;
@@ -1062,6 +1149,29 @@ inline void QTextTableCellFormat::setPadding(qreal padding)
     setRightPadding(padding);
 }
 
+inline void QTextTableCellFormat::setBorder(qreal width)
+{
+    setTopBorder(width);
+    setBottomBorder(width);
+    setLeftBorder(width);
+    setRightBorder(width);
+}
+
+inline void QTextTableCellFormat::setBorderStyle(QTextFrameFormat::BorderStyle style)
+{
+    setTopBorderStyle(style);
+    setBottomBorderStyle(style);
+    setLeftBorderStyle(style);
+    setRightBorderStyle(style);
+}
+
+inline void QTextTableCellFormat::setBorderBrush(const QBrush &brush)
+{
+    setTopBorderBrush(brush);
+    setBottomBorderBrush(brush);
+    setLeftBorderBrush(brush);
+    setRightBorderBrush(brush);
+}
 
 QT_END_NAMESPACE