Support CSS text-decoration-color in underlines, overlines, strikethrough

Also add a feature to the textedit example to set this value.

[ChangeLog][QtGui][CSS] The CSS text-decoration-color attribute is now
supported in rich text spans with underlines, overlines and strikethrough.

Fixes: QTBUG-82114
Task-number: QTBUG-39617
Change-Id: I0065cb5431833da55b0f503ce7ff2b83b74b718a
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@qt.io>

5 files changed, 19 insertions, 0 deletions

diff --git a/examples/widgets/richtext/textedit/images/mac/textundercolor.png b/examples/widgets/richtext/textedit/images/mac/textundercolor.png
new file mode 100644
index 0000000000..30e24e61c3
--- /dev/null
+++ b/examples/widgets/richtext/textedit/images/mac/textundercolor.png
diff --git a/examples/widgets/richtext/textedit/images/win/textundercolor.png b/examples/widgets/richtext/textedit/images/win/textundercolor.png
new file mode 100644
index 0000000000..30e24e61c3
--- /dev/null
+++ b/examples/widgets/richtext/textedit/images/win/textundercolor.png
diff --git a/examples/widgets/richtext/textedit/textedit.cpp b/examples/widgets/richtext/textedit/textedit.cpp
index 3a1b3321a1..ed91f6e250 100644
--- a/examples/widgets/richtext/textedit/textedit.cpp
+++ b/examples/widgets/richtext/textedit/textedit.cpp
@@ -354,6 +354,10 @@ void TextEdit::setupTextActions()
     actionTextColor = menu->addAction(pix, tr("&Color..."), this, &TextEdit::textColor);
     tb->addAction(actionTextColor);
 
+    const QIcon underlineColorIcon(rsrcPath + "/textundercolor.png");
+    actionUnderlineColor = menu->addAction(underlineColorIcon, tr("Underline color..."), this, &TextEdit::underlineColor);
+    tb->addAction(actionUnderlineColor);
+
     menu->addSeparator();
 
     const QIcon checkboxIcon = QIcon::fromTheme("status-checkbox-checked", QIcon(rsrcPath + "/checkbox-checked.png"));
@@ -729,6 +733,17 @@ void TextEdit::textColor()
     colorChanged(col);
 }
 
+void TextEdit::underlineColor()
+{
+    QColor col = QColorDialog::getColor(Qt::black, this);
+    if (!col.isValid())
+        return;
+    QTextCharFormat fmt;
+    fmt.setUnderlineColor(col);
+    mergeFormatOnWordOrSelection(fmt);
+    colorChanged(col);
+}
+
 void TextEdit::textAlign(QAction *a)
 {
     if (a == actionAlignLeft)
diff --git a/examples/widgets/richtext/textedit/textedit.h b/examples/widgets/richtext/textedit/textedit.h
index 07a307f83d..debc401150 100644
--- a/examples/widgets/richtext/textedit/textedit.h
+++ b/examples/widgets/richtext/textedit/textedit.h
@@ -95,6 +95,7 @@ private slots:
     void textSize(const QString &p);
     void textStyle(int styleIndex);
     void textColor();
+    void underlineColor();
     void textAlign(QAction *a);
     void setChecked(bool checked);
     void indent();
@@ -125,6 +126,7 @@ private:
     QAction *actionTextUnderline;
     QAction *actionTextItalic;
     QAction *actionTextColor;
+    QAction *actionUnderlineColor;
     QAction *actionAlignLeft;
     QAction *actionAlignCenter;
     QAction *actionAlignRight;
diff --git a/examples/widgets/richtext/textedit/textedit.qrc b/examples/widgets/richtext/textedit/textedit.qrc
index 1641acc207..a30d50fdbf 100644
--- a/examples/widgets/richtext/textedit/textedit.qrc
+++ b/examples/widgets/richtext/textedit/textedit.qrc
@@ -22,6 +22,7 @@
   <file>images/mac/textleft.png</file>
   <file>images/mac/textright.png</file>
   <file>images/mac/textunder.png</file>
+  <file>images/mac/textundercolor.png</file>
   <file>images/mac/zoomin.png</file>
   <file>images/mac/zoomout.png</file>
   <file>images/win/checkbox.png</file>
@@ -45,6 +46,7 @@
   <file>images/win/textleft.png</file>
   <file>images/win/textright.png</file>
   <file>images/win/textunder.png</file>
+  <file>images/win/textundercolor.png</file>
   <file>images/win/zoomin.png</file>
   <file>images/win/zoomout.png</file>
   <file>example.html</file>