Ensure QDeclarativeTextLayout uses the correct pen

When a styled text specifies a font region with some color set,
QDeclarativeTextLayout used to revert to using a default-constructed
(black-colored) pen for text occurring after the </font> tag, rather
than the "default" (property-defined) color.

This commit ensures that the correct pen is used, by setting the pen
of the "inert" painter to be an invalid color rather than a default
constructed pen.  It then detects when the current pen transitions
back to this invalid pen, and switches back to using the default
color.

Task-number: QTBUG-28135
Change-Id: I6bcc43fbcf7fb2c680959d27b1422364ebb473ae
Reviewed-by: Alan Alpert <aalpert@rim.com>
Reviewed-by: Robin Burchell <robin+qt@viroteck.net>

1 files changed, 12 insertions, 1 deletions

diff --git a/src/declarative/graphicsitems/qdeclarativetextlayout.cpp b/src/declarative/graphicsitems/qdeclarativetextlayout.cpp
index 14a41c05..1eea36eb 100644
--- a/src/declarative/graphicsitems/qdeclarativetextlayout.cpp
+++ b/src/declarative/graphicsitems/qdeclarativetextlayout.cpp
@@ -237,7 +237,10 @@ class DrawTextItemDevice: public QPaintDevice
 
 struct InertTextPainter {
     InertTextPainter()
-    : device(true, true), painter(&device) {}
+    : device(true, true), painter(&device)
+    {
+        painter.setPen(QPen(QColor())); // explicitly invalid color.
+    }
 
     DrawTextItemDevice device;
     QPainter painter;
@@ -373,11 +376,19 @@ void QDeclarativeTextLayout::draw(QPainter *painter, const QPointF &p)
 
     QPen oldPen = priv->state->pen;
     QColor currentColor = oldPen.color();
+    QColor defaultColor = currentColor;
     for (int ii = 0; ii < itemCount; ++ii) {
         QStaticTextItem &item = d->items[ii];
         if (item.color.isValid() && currentColor != item.color) {
+            // up-edge of a <font color="">text</font> tag
+            // we set the painter pen to the text item's specified color.
             painter->setPen(item.color);
             currentColor = item.color;
+        } else if (!item.color.isValid() && currentColor != defaultColor) {
+            // down-edge of a <font color="">text</font> tag
+            // we reset the painter pen back to the default color.
+            currentColor = defaultColor;
+            painter->setPen(currentColor);
         }
         priv->extended->drawStaticTextItem(&item);