TextEdit/TextArea: don't deselect on release if IM just selected text

After 90d3fac73a10b9363fd34e6757cc730d7a0c086c we got a regression on
Android at least: if you long-press to select a word, selection handles
appear; then when you release, there's a QTouchEvent which is left
unhandled, and then a synth-mouse release. In this case, we don't want
to call setCursorPosition(), because it de-selects the selection that
was just made by the input method.

But the intention was to be able to set the cursor position (and also
deselect text) by tapping on a touchscreen on other platforms that don't
have text selection handles. (It seems to be consistent with Android
behavior: there you can also deselect and move the cursor by simply
tapping.) To avoid changing that behavior, we now set a flag if we get
a mouse press and then a QInputMethodEvent with a Selection attribute,
indicating that text got selected that way; and in that case, don't
call setCursorPosition().

Fixes: QTBUG-115004
Change-Id: I7e362da584f6e1cb1509dcc0eff024b291ef5df3
Reviewed-by: Santhosh Kumar <santhosh.kumar.selvaraj@qt.io>
Reviewed-by: Rami Potinkara <rami.potinkara@qt.io>
(cherry picked from commit c1d5e46ea79762bfcc070fabbf10ff7fdf184e01)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>
(cherry picked from commit 2ee61d7dac1df2e7f7e0e6b789bf2176c44f079f)

3 files changed, 41 insertions, 1 deletions

diff --git a/src/quick/items/qquicktextcontrol.cpp b/src/quick/items/qquicktextcontrol.cpp
index 929ce10136..510ece726a 100644
--- a/src/quick/items/qquicktextcontrol.cpp
+++ b/src/quick/items/qquicktextcontrol.cpp
@@ -81,6 +81,7 @@ QQuickTextControlPrivate::QQuickTextControlPrivate()
       cursorRectangleChanged(false),
       hoveredMarker(false),
       selectByTouchDrag(false),
+      imSelectionAfterPress(false),
       lastSelectionStart(-1),
       lastSelectionEnd(-1)
 {}
@@ -992,6 +993,7 @@ void QQuickTextControlPrivate::mousePressEvent(QMouseEvent *e, const QPointF &po
 
     mousePressed = (interactionFlags & Qt::TextSelectableByMouse) && (e->button() & Qt::LeftButton);
     mousePressPos = pos.toPoint();
+    imSelectionAfterPress = false;
 
     if (sendMouseEventToInputContext(e, pos))
         return;
@@ -1177,7 +1179,7 @@ void QQuickTextControlPrivate::mouseReleaseEvent(QMouseEvent *e, const QPointF &
             q->insertFromMimeData(md);
 #endif
     }
-    if (!isMouse && !selectByTouchDrag && interactionFlags.testFlag(Qt::TextEditable))
+    if (!isMouse && !selectByTouchDrag && !imSelectionAfterPress && interactionFlags.testFlag(Qt::TextEditable))
         setCursorPosition(pos);
 
     repaintOldAndNewSelection(oldSelection);
@@ -1322,6 +1324,8 @@ void QQuickTextControlPrivate::inputMethodEvent(QInputMethodEvent *e)
         for (int i = 0; i < e->attributes().size(); ++i) {
             const QInputMethodEvent::Attribute &a = e->attributes().at(i);
             if (a.type == QInputMethodEvent::Selection) {
+                if (mousePressed)
+                    imSelectionAfterPress = true;
                 QTextCursor oldCursor = cursor;
                 int blockStart = a.start + cursor.block().position();
                 cursor.setPosition(blockStart, QTextCursor::MoveAnchor);
diff --git a/src/quick/items/qquicktextcontrol_p_p.h b/src/quick/items/qquicktextcontrol_p_p.h
index 5717cf6377..f04d298e4a 100644
--- a/src/quick/items/qquicktextcontrol_p_p.h
+++ b/src/quick/items/qquicktextcontrol_p_p.h
@@ -131,6 +131,7 @@ public:
     bool cursorRectangleChanged : 1;
     bool hoveredMarker: 1;
     bool selectByTouchDrag: 1;
+    bool imSelectionAfterPress: 1;
 
     int lastSelectionStart;
     int lastSelectionEnd;
diff --git a/tests/auto/quick/qquicktextedit/tst_qquicktextedit.cpp b/tests/auto/quick/qquicktextedit/tst_qquicktextedit.cpp
index dc7342d162..9819494d34 100644
--- a/tests/auto/quick/qquicktextedit/tst_qquicktextedit.cpp
+++ b/tests/auto/quick/qquicktextedit/tst_qquicktextedit.cpp
@@ -207,6 +207,8 @@ private slots:
     void touchscreenDoesNotSelect();
     void touchscreenSetsFocusAndMovesCursor();
 
+    void longPressInputMethod();
+
     void rtlAlignmentInColumnLayout_QTBUG_112858();
 
 private:
@@ -6524,6 +6526,39 @@ void tst_qquicktextedit::touchscreenSetsFocusAndMovesCursor()
     QVERIFY(top->selectedText().isEmpty());
 }
 
+void tst_qquicktextedit::longPressInputMethod() // QTBUG-115004
+{
+    QQuickView window;
+    window.setMinimumWidth(200);
+    window.setMinimumHeight(100);
+    QVERIFY(QQuickTest::showView(window, testFileUrl("positionAt.qml")));
+    QQuickTextEdit *edit = qobject_cast<QQuickTextEdit *>(window.rootObject());
+    QVERIFY(edit);
+
+    // Realistically there are touch events. But QQuickTextEdit doesn't handle them yet;
+    // so we only test the synth-mouse events for now.
+    QPoint pos = edit->positionToRectangle(20).center().toPoint(); // in the word "pi|ece"
+    QTest::mousePress(&window, Qt::LeftButton, {}, pos);
+
+    // Simulate input method events as seen on Android during long-press
+    {
+        QInputMethodEvent imEvent({}, QList<QInputMethodEvent::Attribute>()
+                                          << QInputMethodEvent::Attribute(QInputMethodEvent::Selection, 20, 0, {}));
+        QCoreApplication::sendEvent(edit, &imEvent);
+    }
+    {
+        QInputMethodEvent imEvent({}, QList<QInputMethodEvent::Attribute>()
+                                          << QInputMethodEvent::Attribute(QInputMethodEvent::Cursor, 0, 0, {})
+                                          << QInputMethodEvent::Attribute(QInputMethodEvent::Selection, 13, -5, {}));
+        QCoreApplication::sendEvent(edit, &imEvent);
+    }
+
+    // Release later => long press
+    QTest::mouseRelease(&window, Qt::LeftButton, {}, pos, 1500);
+
+    QTRY_COMPARE(edit->selectedText(), "piece");
+}
+
 void tst_qquicktextedit::rtlAlignmentInColumnLayout_QTBUG_112858()
 {
     QQuickView window(testFileUrl("qtbug-112858.qml"));