Android: Add select and copy capability to read-only text widgets

In case of a read-only text editing widget it was imposibble to copy text
from it. In QtWidgets you could not even see the selection handless.
Text selection in QtWidgets module was filtered depending on readOnly
property of the widget. Additionally, in InputMethod the read-only state
was translated into disabled.

Patch also makes the edit menu to be aware of the read-only status of
the control - the menu items are different for rw and ro controls.

Task-number: QTBUG-91417
Change-Id: Ic7b27f78678eeaa87a38607af787f254db1383b8
Reviewed-by: Rami Potinkara <rami.potinkara@qt.io>
Reviewed-by: Ville Voutilainen <ville.voutilainen@qt.io>

src/android/jar/src/org/qtproject/qt/android/QtActivityDelegate.java

@@ -566,9 +566,7 @@ public class QtActivityDelegate
                 break;
         }
 
-        if (QtNative.hasClipboardText())
-            editButtons |= EditContextView.PASTE_BUTTON;
-        else
+        if (!QtNative.hasClipboardText())
             editButtons &= ~EditContextView.PASTE_BUTTON;
 
         if ((mode & CursorHandleShowEdit) == CursorHandleShowEdit && editButtons != 0) {

src/corelib/global/qnamespace.h

@@ -1394,6 +1394,7 @@ namespace Qt {
         ImAnchorRectangle = 0x4000,
         ImInputItemClipRectangle = 0x8000,
 
+        ImReadOnly = 0x10000,
         ImPlatformData = 0x80000000,
         ImQueryInput = ImCursorRectangle | ImCursorPosition | ImSurroundingText |
                        ImCurrentSelection | ImAnchorRectangle | ImAnchorPosition,

src/plugins/platforms/android/qandroidinputcontext.cpp

@@ -604,34 +604,34 @@ void QAndroidInputContext::updateCursorPosition()
 void QAndroidInputContext::updateSelectionHandles()
 {
     static bool noHandles = qEnvironmentVariableIntValue("QT_QPA_NO_TEXT_HANDLES");
-    if (noHandles)
+    if (noHandles || !m_focusObject)
         return;
 
     auto im = qGuiApp->inputMethod();
-    if (!m_focusObject || ((m_handleMode & 0xff) == Hidden)) {
-        // Hide the handles
-        QtAndroidInput::updateHandles(Hidden);
-        return;
-    }
 
-    QInputMethodQueryEvent query(Qt::ImCursorPosition | Qt::ImAnchorPosition | Qt::ImEnabled | Qt::ImCurrentSelection | Qt::ImHints | Qt::ImSurroundingText);
+
+    QInputMethodQueryEvent query(Qt::ImCursorPosition | Qt::ImAnchorPosition | Qt::ImEnabled
+                                 | Qt::ImCurrentSelection | Qt::ImHints | Qt::ImSurroundingText
+                                 | Qt::ImReadOnly);
     QCoreApplication::sendEvent(m_focusObject, &query);
 
     int cpos = query.value(Qt::ImCursorPosition).toInt();
     int anchor = query.value(Qt::ImAnchorPosition).toInt();
+    const QVariant readOnlyVariant = query.value(Qt::ImReadOnly);
+    bool readOnly = readOnlyVariant.toBool();
+
+    if ( cpos == anchor && (!readOnlyVariant.isValid() || readOnly)) {
+        QtAndroidInput::updateHandles(Hidden);
+        return;
+    }
 
     if (cpos == anchor || im->anchorRectangle().isNull()) {
-        if (!query.value(Qt::ImEnabled).toBool()) {
-            QtAndroidInput::updateHandles(Hidden);
-            return;
-        }
-
         auto curRect = cursorRectangle();
         QPoint cursorPoint = qGuiApp->focusWindow()->handle()->mapToGlobal(QPoint(curRect.x() + (curRect.width() / 2), curRect.y() + curRect.height()));
         QPoint editMenuPoint(cursorPoint.x(), cursorPoint.y());
         m_handleMode &= ShowEditPopup;
         m_handleMode |= ShowCursor;
-        uint32_t buttons = EditContext::PasteButton;
+        uint32_t buttons = readOnly ? 0 : EditContext::PasteButton;
         if (!query.value(Qt::ImSurroundingText).toString().isEmpty())
             buttons |= EditContext::SelectAllButton;
         QtAndroidInput::updateHandles(m_handleMode, editMenuPoint, buttons, cursorPoint);
@@ -650,7 +650,10 @@ void QAndroidInputContext::updateSelectionHandles()
     QPoint leftPoint(leftRect.bottomLeft().toPoint());
     QPoint righPoint(rightRect.bottomRight().toPoint());
     QPoint editPoint(leftRect.united(rightRect).topLeft().toPoint());
-    QtAndroidInput::updateHandles(m_handleMode, editPoint, EditContext::AllButtons, leftPoint, righPoint,
+    uint32_t buttons = readOnly ? EditContext::CopyButton | EditContext::SelectAllButton
+                                : EditContext::AllButtons;
+
+    QtAndroidInput::updateHandles(m_handleMode, editPoint, buttons, leftPoint, righPoint,
                                   query.value(Qt::ImCurrentSelection).toString().isRightToLeft());
     m_hideCursorHandleTimer.stop();
 }

src/widgets/widgets/qlineedit.cpp

@@ -1806,7 +1806,7 @@ QRect QLineEdit::cursorRect() const
 void QLineEdit::inputMethodEvent(QInputMethodEvent *e)
 {
     Q_D(QLineEdit);
-    if (d->control->isReadOnly()) {
+    if (!d->shouldEnableInputMethod()) {
         e->ignore();
         return;
     }
@@ -1874,6 +1874,20 @@ QVariant QLineEdit::inputMethodQuery(Qt::InputMethodQuery property, QVariant arg
             return QVariant(d->control->selectionEnd());
         else
             return QVariant(d->control->selectionStart());
+    case Qt::ImReadOnly:
+        return isReadOnly();
+    case Qt::ImTextBeforeCursor: {
+        const QPointF pt = argument.toPointF();
+        if (!pt.isNull())
+            return d->textBeforeCursor(d->xToPos(pt.x(), QTextLine::CursorBetweenCharacters));
+        else
+            return d->textBeforeCursor(d->control->cursor()); }
+    case Qt::ImTextAfterCursor: {
+        const QPointF pt = argument.toPointF();
+        if (!pt.isNull())
+            return d->textAfterCursor(d->xToPos(pt.x(), QTextLine::CursorBetweenCharacters));
+        else
+            return d->textAfterCursor(d->control->cursor()); }
     default:
         return QWidget::inputMethodQuery(property);
     }

src/widgets/widgets/qlineedit_p.cpp

@@ -86,6 +86,18 @@ int QLineEditPrivate::xToPos(int x, QTextLine::CursorPosition betweenOrOn) const
     return control->xToPos(x, betweenOrOn);
 }
 
+QString QLineEditPrivate::textBeforeCursor(int curPos) const
+{
+    const QString &text = control->text();
+    return text.mid(0, curPos);
+}
+
+QString QLineEditPrivate::textAfterCursor(int curPos) const
+{
+    const QString &text = control->text();
+    return text.mid(curPos);
+}
+
 bool QLineEditPrivate::inSelection(int x) const
 {
     x -= adjustedContentsRect().x() - hscroll + horizontalMargin;

src/widgets/widgets/qlineedit_p.h

@@ -179,13 +179,19 @@ public:
     void setCursorVisible(bool visible);
     void setText(const QString& text);
 
+    QString textBeforeCursor(int curPos) const;
+    QString textAfterCursor(int curPos) const;
     void updatePasswordEchoEditing(bool);
 
     void resetInputMethod();
 
     inline bool shouldEnableInputMethod() const
     {
+#if defined (Q_OS_ANDROID)
+        return !control->isReadOnly() || control->isSelectableByMouse();
+#else
         return !control->isReadOnly();
+#endif
     }
     inline bool shouldShowPlaceholderText() const
     {

src/widgets/widgets/qplaintextedit.cpp

@@ -71,9 +71,14 @@
 
 QT_BEGIN_NAMESPACE
 
-static inline bool shouldEnableInputMethod(QPlainTextEdit *plaintextedit)
+static inline bool shouldEnableInputMethod(QPlainTextEdit *control)
 {
-    return !plaintextedit->isReadOnly();
+#if defined(Q_OS_ANDROID)
+    Q_UNUSED(control);
+    return !control->isReadOnly() || (control->textInteractionFlags() & Qt::TextSelectableByMouse);
+#else
+    return !control->isReadOnly();
+#endif
 }
 
 class QPlainTextDocumentLayoutPrivate : public QAbstractTextDocumentLayoutPrivate
@@ -2238,6 +2243,8 @@ QVariant QPlainTextEdit::inputMethodQuery(Qt::InputMethodQuery query, QVariant a
         case Qt::ImHints:
         case Qt::ImInputItemClipRectangle:
         return QWidget::inputMethodQuery(query);
+    case Qt::ImReadOnly:
+        return isReadOnly();
     default:
         break;
     }

src/widgets/widgets/qtextbrowser.cpp

@@ -57,6 +57,15 @@
 
 QT_BEGIN_NAMESPACE
 
+static inline bool shouldEnableInputMethod(QTextBrowser *texbrowser)
+{
+#if defined (Q_OS_ANDROID)
+    return !texbrowser->isReadOnly() || (texbrowser->textInteractionFlags() & Qt::TextSelectableByMouse);
+#else
+    return !texbrowser->isReadOnly();
+#endif
+}
+
 Q_LOGGING_CATEGORY(lcBrowser, "qt.text.browser")
 
 class QTextBrowserPrivate : public QTextEditPrivate
@@ -692,7 +701,7 @@ void QTextBrowserPrivate::init()
 #ifndef QT_NO_CURSOR
     viewport->setCursor(oldCursor);
 #endif
-    q->setAttribute(Qt::WA_InputMethodEnabled, !q->isReadOnly());
+    q->setAttribute(Qt::WA_InputMethodEnabled, shouldEnableInputMethod(q));
     q->setUndoRedoEnabled(false);
     viewport->setMouseTracking(true);
     QObject::connect(q->document(), SIGNAL(contentsChanged()), q, SLOT(_q_documentModified()));

src/widgets/widgets/qtextedit.cpp

@@ -79,7 +79,11 @@ QT_BEGIN_NAMESPACE
 
 static inline bool shouldEnableInputMethod(QTextEdit *textedit)
 {
+#if defined (Q_OS_ANDROID)
+    return !textedit->isReadOnly() || (textedit->textInteractionFlags() & Qt::TextSelectableByMouse);
+#else
     return !textedit->isReadOnly();
+#endif
 }
 
 class QTextEditControl : public QWidgetTextControl
@@ -1832,6 +1836,8 @@ QVariant QTextEdit::inputMethodQuery(Qt::InputMethodQuery query, QVariant argume
         case Qt::ImHints:
         case Qt::ImInputItemClipRectangle:
         return QWidget::inputMethodQuery(query);
+    case Qt::ImReadOnly:
+        return isReadOnly();
     default:
         break;
     }

src/widgets/widgets/qwidgetlinecontrol_p.h

@@ -164,6 +164,9 @@ public:
 
     int selectionStart() const { return hasSelectedText() ? m_selstart : -1; }
     int selectionEnd() const { return hasSelectedText() ? m_selend : -1; }
+#if defined (Q_OS_ANDROID)
+    bool isSelectableByMouse() const { return true; }
+#endif
     bool inSelection(int x) const
     {
         if (m_selstart >= m_selend)

src/widgets/widgets/qwidgettextcontrol.cpp

@@ -2039,7 +2039,7 @@ bool QWidgetTextControlPrivate::dropEvent(const QMimeData *mimeData, const QPoin
 void QWidgetTextControlPrivate::inputMethodEvent(QInputMethodEvent *e)
 {
     Q_Q(QWidgetTextControl);
-    if (!(interactionFlags & Qt::TextEditable) || cursor.isNull()) {
+    if (!(interactionFlags & (Qt::TextEditable | Qt::TextSelectableByMouse)) || cursor.isNull()) {
         e->ignore();
         return;
     }

tests/auto/widgets/widgets/qtextbrowser/tst_qtextbrowser.cpp

@@ -466,11 +466,29 @@ void tst_QTextBrowser::textInteractionFlags_vs_readOnly()
 void tst_QTextBrowser::inputMethodAttribute_vs_readOnly()
 {
     QVERIFY(browser->isReadOnly());
+#if defined(Q_OS_ANDROID)
+    QInputMethodQueryEvent query(Qt::ImReadOnly);
+    QCoreApplication::sendEvent(browser, &query);
+    QVERIFY(query.value(Qt::ImReadOnly).toBool());
+#else
     QVERIFY(!browser->testAttribute(Qt::WA_InputMethodEnabled));
+#endif
+
     browser->setReadOnly(false);
+#if defined(Q_OS_ANDROID)
+    QCoreApplication::sendEvent(browser, &query);
+    QVERIFY(!query.value(Qt::ImReadOnly).toBool());
+#else
     QVERIFY(browser->testAttribute(Qt::WA_InputMethodEnabled));
+#endif
+
     browser->setReadOnly(true);
+#if defined(Q_OS_ANDROID)
+    QCoreApplication::sendEvent(browser, &query);
+    QVERIFY(query.value(Qt::ImReadOnly).toBool());
+#else
     QVERIFY(!browser->testAttribute(Qt::WA_InputMethodEnabled));
+#endif
 }
 
 void tst_QTextBrowser::anchorsWithSelfBuiltHtml()