Add methods to convert QFont to/from mime data

nyalldawson · nyalldawson · commit 5ac9745cad22 · 2017-07-06T19:56:39.000+10:00
diff --git a/python/core/qgsfontutils.sip b/python/core/qgsfontutils.sip
@@ -9,6 +9,7 @@
 
 
 
+
 class QgsFontUtils
 {
 
@@ -136,6 +137,24 @@ class QgsFontUtils
  :rtype: bool
 %End
 
+    static QMimeData *toMimeData( const QFont &font ) /Factory/;
+%Docstring
+ Returns new mime data representing the specified ``font`` settings.
+ Caller takes responsibility for deleting the returned object.
+.. seealso:: fromMimeData()
+.. versionadded:: 3.0
+ :rtype: QMimeData
+%End
+
+    static QFont fromMimeData( const QMimeData *data, bool *ok /Out/ = 0 );
+%Docstring
+ Attempts to parse the provided mime ``data`` as a QFont.
+ If data can be parsed as a QFont, ``ok`` will be set to true.
+.. seealso:: toMimeData()
+.. versionadded:: 3.0
+ :rtype: QFont
+%End
+
     static QString translateNamedStyle( const QString &namedStyle );
 %Docstring
  Returns the localized named style of a font, if such a translation is available.
diff --git a/src/core/qgsfontutils.cpp b/src/core/qgsfontutils.cpp
@@ -24,7 +24,8 @@
 #include <QFontDatabase>
 #include <QFontInfo>
 #include <QStringList>
-
+#include <QMimeData>
+#include <memory>
 
 bool QgsFontUtils::fontMatchOnSystem( const QFont &f )
 {
@@ -360,6 +361,51 @@ bool QgsFontUtils::setFromXmlChildNode( QFont &font, const QDomElement &element,
   }
 }
 
+QMimeData *QgsFontUtils::toMimeData( const QFont &font )
+{
+  std::unique_ptr< QMimeData >mimeData( new QMimeData );
+
+  QDomDocument fontDoc;
+  QDomElement fontElem = toXmlElement( font, fontDoc, QStringLiteral( "font" ) );
+  fontDoc.appendChild( fontElem );
+  mimeData->setText( fontDoc.toString() );
+
+  return mimeData.release();
+}
+
+QFont QgsFontUtils::fromMimeData( const QMimeData *data, bool *ok )
+{
+  QFont font;
+  if ( ok )
+    *ok = false;
+
+  if ( !data )
+    return font;
+
+  QString text = data->text();
+  if ( !text.isEmpty() )
+  {
+    QDomDocument doc;
+    QDomElement elem;
+
+    if ( doc.setContent( text ) )
+    {
+      elem = doc.documentElement();
+
+      if ( elem.nodeName() != QStringLiteral( "font" ) )
+        elem = elem.firstChildElement( QStringLiteral( "font" ) );
+
+      if ( setFromXmlElement( font, elem ) )
+      {
+        if ( ok )
+          *ok = true;
+      }
+      return font;
+    }
+  }
+  return font;
+}
+
 static QMap<QString, QString> createTranslatedStyleMap()
 {
   QMap<QString, QString> translatedStyleMap;
diff --git a/src/core/qgsfontutils.h b/src/core/qgsfontutils.h
@@ -21,6 +21,9 @@
 #include <QDomElement>
 
 #include "qgis_core.h"
+#include "qgis_sip.h"
+
+class QMimeData;
 
 /** \ingroup core
  * \class QgsFontUtils
@@ -120,6 +123,22 @@ class CORE_EXPORT QgsFontUtils
      */
     static bool setFromXmlChildNode( QFont &font, const QDomElement &element, const QString &childNode );
 
+    /**
+     * Returns new mime data representing the specified \a font settings.
+     * Caller takes responsibility for deleting the returned object.
+     * \see fromMimeData()
+     * \since QGIS 3.0
+     */
+    static QMimeData *toMimeData( const QFont &font ) SIP_FACTORY;
+
+    /**
+     * Attempts to parse the provided mime \a data as a QFont.
+     * If data can be parsed as a QFont, \a ok will be set to true.
+     * \see toMimeData()
+     * \since QGIS 3.0
+     */
+    static QFont fromMimeData( const QMimeData *data, bool *ok SIP_OUT = nullptr );
+
     /** Returns the localized named style of a font, if such a translation is available.
      * \param namedStyle a named style, i.e. "Bold", "Italic", etc
      * \returns The localized named style
diff --git a/tests/src/python/test_qgsfontutils.py b/tests/src/python/test_qgsfontutils.py
@@ -66,6 +66,28 @@ def test_get_specific_test_font(self):
         msg = self._family + ' test font Bold Oblique at 14 pt not retrieved'
         assert res, msg
 
+    def testToFromMimeData(self):
+        """
+        Test converting QFonts to and from mime data
+        """
+        f = QgsFontUtils.getStandardTestFont('Bold Oblique', 14)
+        mime_data = QgsFontUtils.toMimeData(f)
+        self.assertTrue(mime_data is not None)
+
+        res, ok = QgsFontUtils.fromMimeData(None)
+        self.assertFalse(ok)
+        res, ok = QgsFontUtils.fromMimeData(mime_data)
+        self.assertTrue(ok)
+
+        expected = (
+            res.family() == self._family and
+            res.bold() and
+            res.italic() and
+            res.pointSize() == 14
+        )
+        msg = self._family + ' test font Bold Oblique at 14 pt not retrieved from mime data'
+        self.assertTrue(res, msg)
+
 
 if __name__ == '__main__':
     unittest.main()
