Fix preedit text visibility for TextEdit

For an empty TextEdit with preedit text, we need to add the text
separately since the blockIterator will not go through that case.
Also fixed preedit text appended at the end of any commited text.

Move the code for adding text into SelectionEngine so that we can
reuse it for adding preedit text.

Task-number: QTBUG-22647
Change-Id: Id4fe04099b16949ff5de0747881c6dc96ef0673f
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@nokia.com>

1 files changed, 55 insertions, 30 deletions

diff --git a/src/quick/items/qquicktextnode.cpp b/src/quick/items/qquicktextnode.cpp
index fcb1c855ec..b5c71d0b7a 100644
--- a/src/quick/items/qquicktextnode.cpp
+++ b/src/quick/items/qquicktextnode.cpp
@@ -329,6 +329,12 @@ namespace {
         void addImage(const QRectF &rect, const QImage &image, qreal ascent,
                       BinaryTreeNode::SelectionState selectionState,
                       QTextFrameFormat::Position layoutPosition);
+        int addText(const QTextBlock &block,
+                    const QTextCharFormat &charFormat,
+                    const QColor &textColor,
+                    const QVarLengthArray<QTextLayout::FormatRange> &colorChanges,
+                    int textPos, int fragmentEnd,
+                    int selectionStart, int selectionEnd);
         void addTextObject(const QPointF &position, const QTextCharFormat &format,
                            BinaryTreeNode::SelectionState selectionState,
                            QTextDocument *textDocument, int pos,
@@ -407,6 +413,45 @@ namespace {
         QList<QPair<QRectF, QImage> > m_images;
     };
 
+    int SelectionEngine::addText(const QTextBlock &block,
+                                 const QTextCharFormat &charFormat,
+                                 const QColor &textColor,
+                                 const QVarLengthArray<QTextLayout::FormatRange> &colorChanges,
+                                 int textPos, int fragmentEnd,
+                                 int selectionStart, int selectionEnd)
+    {
+        if (charFormat.foreground().style() != Qt::NoBrush)
+            setTextColor(charFormat.foreground().color());
+        else
+            setTextColor(textColor);
+
+        while (textPos < fragmentEnd) {
+            int blockRelativePosition = textPos - block.position();
+            QTextLine line = block.layout()->lineForTextPosition(blockRelativePosition);
+            if (!currentLine().isValid()
+                || line.lineNumber() != currentLine().lineNumber()) {
+                setCurrentLine(line);
+            }
+
+            Q_ASSERT(line.textLength() > 0);
+            int lineEnd = line.textStart() + block.position() + line.textLength();
+
+            int len = qMin(lineEnd - textPos, fragmentEnd - textPos);
+            Q_ASSERT(len > 0);
+
+            int currentStepEnd = textPos + len;
+
+            addGlyphsForRanges(colorChanges,
+                               textPos - block.position(),
+                               currentStepEnd - block.position(),
+                               selectionStart - block.position(),
+                               selectionEnd - block.position());
+
+            textPos = currentStepEnd;
+        }
+        return textPos;
+    }
+
     void SelectionEngine::addTextDecorations(const QVarLengthArray<TextDecoration> &textDecorations,
                                              qreal offset, qreal thickness)
     {
@@ -1155,6 +1200,13 @@ void QQuickTextNode::addTextDocument(const QPointF &, QTextDocument *textDocumen
 
                 int textPos = block.position();
                 QTextBlock::iterator blockIterator = block.begin();
+                if (blockIterator.atEnd() && preeditLength) {
+                    engine.setPosition(blockPosition);
+                    textPos = engine.addText(block, block.charFormat(), textColor, colorChanges,
+                                             textPos, textPos + preeditLength,
+                                             selectionStart, selectionEnd);
+                }
+
                 while (!blockIterator.atEnd()) {
                     QTextFragment fragment = blockIterator.fragment();
                     QString text = fragment.text();
@@ -1183,42 +1235,15 @@ void QQuickTextNode::addTextDocument(const QPointF &, QTextDocument *textDocumen
                         }
                         textPos += text.length();
                     } else {
-                        if (charFormat.foreground().style() != Qt::NoBrush)
-                            engine.setTextColor(charFormat.foreground().color());
-                        else
-                            engine.setTextColor(textColor);
-
                         int fragmentEnd = textPos + fragment.length();
                         if (preeditPosition >= 0
                          && preeditPosition >= textPos
-                         && preeditPosition < fragmentEnd) {
+                         && preeditPosition <= fragmentEnd) {
                             fragmentEnd += preeditLength;
                         }
 
-                        while (textPos < fragmentEnd) {
-                            int blockRelativePosition = textPos - block.position();
-                            QTextLine line = block.layout()->lineForTextPosition(blockRelativePosition);
-                            if (!engine.currentLine().isValid()
-                                    || line.lineNumber() != engine.currentLine().lineNumber()) {
-                                engine.setCurrentLine(line);
-                            }
-
-                            Q_ASSERT(line.textLength() > 0);
-                            int lineEnd = line.textStart() + block.position() + line.textLength();
-
-                            int len = qMin(lineEnd - textPos, fragmentEnd - textPos);
-                            Q_ASSERT(len > 0);
-
-                            int currentStepEnd = textPos + len;
-
-                            engine.addGlyphsForRanges(colorChanges,
-                                                      textPos - block.position(),
-                                                      currentStepEnd - block.position(),
-                                                      selectionStart - block.position(),
-                                                      selectionEnd - block.position());
-
-                            textPos = currentStepEnd;
-                        }
+                        engine.addText(block, charFormat, textColor, colorChanges, textPos, fragmentEnd,
+                                       selectionStart, selectionEnd);
                     }
 
                     ++blockIterator;