QQuickTextControl: Emit cursorPositionChanged() when handling IM event

QQuickTextControl and consequently QQuickTextEdit did not emit
cursorPositionChanged() signal when cursor position was changed by a
QInputMethodEvent with a QInputMethodEvent::Selection attribute.

This is especially important on Android because QAndroidInputContext
uses such events extensively to move the cursor and also relies on
cursorPositionChanged() signal being emitted by the focus object. If the
signal is not emitted, QAndroidInputContext does not notify the virtual
keyboard about cursor position change which results in various glitches.

Change-Id: I46bef6185463d11507b1b96435fdc056bbe951f2
Reviewed-by: Shawn Rutledge <shawn.rutledge@qt.io>
Reviewed-by: Richard Moe Gustavsen <richard.gustavsen@qt.io>

1 files changed, 3 insertions, 0 deletions

diff --git a/src/quick/items/qquicktextcontrol.cpp b/src/quick/items/qquicktextcontrol.cpp
index 38ca7283b4..1dd593cc1a 100644
--- a/src/quick/items/qquicktextcontrol.cpp
+++ b/src/quick/items/qquicktextcontrol.cpp
@@ -1297,6 +1297,7 @@ void QQuickTextControlPrivate::inputMethodEvent(QInputMethodEvent *e)
             || e->preeditString() != cursor.block().layout()->preeditAreaText()
             || e->replacementLength() > 0;
     bool forceSelectionChanged = false;
+    int oldCursorPos = cursor.position();
 
     cursor.beginEditBlock();
     if (isGettingInput) {
@@ -1365,6 +1366,8 @@ void QQuickTextControlPrivate::inputMethodEvent(QInputMethodEvent *e)
     QTextCursorPrivate *cursor_d = QTextCursorPrivate::getPrivate(&cursor);
     if (cursor_d)
         cursor_d->setX();
+    if (cursor.position() != oldCursorPos)
+        emit q->cursorPositionChanged();
     q->updateCursorRectangle(oldPreeditCursor != preeditCursor || forceSelectionChanged || isGettingInput);
     selectionChanged(forceSelectionChanged);
 }