preserve HTML heading level in QTextBlockFormat; demonstrate in example

When reading an HTML file with <H1> for example, we still set the font
size as before (that's how it always was done),
but now it remembers that it came from an H1 tag, so it writes
<h1 ...><span font-size:xx-large ...> ...  rather than
<p ...><span ...> ...  This will help with the upcoming Markdown
format, where heading level is saved but the font is not.

Now the style combobox in examples/widgets/richtext/textedit can set
list item type, heading type or "standard" formatting, and also shows the
current formatting of the line that has the cursor.  It was always a
shortcoming in this example that it only allowed setting the current line's
block format but had no feedback to show the current format.

Change-Id: I0a7849b74f23fea84d3375c487c3a6b9f43240c1
Reviewed-by: Lars Knoll <lars.knoll@qt.io>

1 files changed, 35 insertions, 1 deletions

diff --git a/src/gui/text/qtextdocumentfragment.cpp b/src/gui/text/qtextdocumentfragment.cpp
index ea37695f4e..3ad49b3f88 100644
--- a/src/gui/text/qtextdocumentfragment.cpp
+++ b/src/gui/text/qtextdocumentfragment.cpp
@@ -420,7 +420,7 @@ static QTextListFormat::Style nextListStyle(QTextListFormat::Style style)
 }
 
 QTextHtmlImporter::QTextHtmlImporter(QTextDocument *_doc, const QString &_html, ImportMode mode, const QTextDocument *resourceProvider)
-    : indent(0), compressNextWhitespace(PreserveWhiteSpace), doc(_doc), importMode(mode)
+    : indent(0), headingLevel(0), compressNextWhitespace(PreserveWhiteSpace), doc(_doc), importMode(mode)
 {
     cursor = QTextCursor(doc);
     wsm = QTextHtmlParserNode::WhiteSpaceNormal;
@@ -747,8 +747,28 @@ QTextHtmlImporter::ProcessNodeResult QTextHtmlImporter::processSpecialNodes()
             return ContinueWithNextNode;
         }
 
+        case Html_h1:
+            headingLevel = 1;
+            break;
+        case Html_h2:
+            headingLevel = 2;
+            break;
+        case Html_h3:
+            headingLevel = 3;
+            break;
+        case Html_h4:
+            headingLevel = 4;
+            break;
+        case Html_h5:
+            headingLevel = 5;
+            break;
+        case Html_h6:
+            headingLevel = 6;
+            break;
+
         default: break;
     }
+
     return ContinueWithCurrentNode;
 }
 
@@ -832,6 +852,15 @@ bool QTextHtmlImporter::closeTag()
                     }
                 }
                 break;
+            case Html_h1:
+            case Html_h2:
+            case Html_h3:
+            case Html_h4:
+            case Html_h5:
+            case Html_h6:
+                headingLevel = 0;
+                blockTagClosed = true;
+                break;
             default:
                 if (closedNode->isBlock())
                     blockTagClosed = true;
@@ -1093,6 +1122,11 @@ QTextHtmlImporter::ProcessNodeResult QTextHtmlImporter::processBlockNode()
         modifiedBlockFormat = true;
     }
 
+    if (headingLevel) {
+        block.setHeadingLevel(headingLevel);
+        modifiedBlockFormat = true;
+    }
+
     if (currentNode->blockFormat.propertyCount() > 0) {
         modifiedBlockFormat = true;
         block.merge(currentNode->blockFormat);