3 files changed, 88 insertions, 30 deletions

diff --git a/src/widgets/widgets/qlineedit.cpp b/src/widgets/widgets/qlineedit.cpp
index 242a4405ca..2ae2e16c89 100644
--- a/src/widgets/widgets/qlineedit.cpp
+++ b/src/widgets/widgets/qlineedit.cpp
@@ -488,7 +488,10 @@ void QLineEdit::setClearButtonEnabled(bool enable)
         QAction *clearAction = new QAction(d->clearButtonIcon(), QString(), this);
         clearAction->setEnabled(!isReadOnly());
         clearAction->setObjectName(QLatin1String(clearButtonActionNameC));
-        d->addAction(clearAction, 0, QLineEdit::TrailingPosition, QLineEditPrivate::SideWidgetClearButton | QLineEditPrivate::SideWidgetFadeInWithText);
+
+        int flags = QLineEditPrivate::SideWidgetClearButton | QLineEditPrivate::SideWidgetFadeInWithText;
+        auto widgetAction = d->addAction(clearAction, nullptr, QLineEdit::TrailingPosition, flags);
+        widgetAction->setVisible(!text().isEmpty());
     } else {
         QAction *clearAction = findChild<QAction *>(QLatin1String(clearButtonActionNameC));
         Q_ASSERT(clearAction);
diff --git a/src/widgets/widgets/qlineedit_p.cpp b/src/widgets/widgets/qlineedit_p.cpp
index df8d534afa..6dcb2dd693 100644
--- a/src/widgets/widgets/qlineedit_p.cpp
+++ b/src/widgets/widgets/qlineedit_p.cpp
@@ -392,9 +392,47 @@ void QLineEditIconButton::setOpacity(qreal value)
 }
 
 #if QT_CONFIG(animation)
+bool QLineEditIconButton::shouldHideWithText() const
+{
+    return m_hideWithText;
+}
+
+void QLineEditIconButton::setHideWithText(bool hide)
+{
+    m_hideWithText = hide;
+}
+
+void QLineEditIconButton::onAnimationFinished()
+{
+    if (shouldHideWithText() && isVisible() && !m_wasHidden) {
+        hide();
+
+        // Invalidate previous geometry to take into account new size of side widgets
+        if (auto le = lineEditPrivate())
+            le->updateGeometry_helper(true);
+    }
+}
+
+void QLineEditIconButton::animateShow(bool visible)
+{
+    m_wasHidden = visible;
+
+    if (shouldHideWithText() && !isVisible()) {
+        show();
+
+        // Invalidate previous geometry to take into account new size of side widgets
+        if (auto le = lineEditPrivate())
+            le->updateGeometry_helper(true);
+    }
+
+    startOpacityAnimation(visible ? 1.0 : 0.0);
+}
+
 void QLineEditIconButton::startOpacityAnimation(qreal endValue)
 {
     QPropertyAnimation *animation = new QPropertyAnimation(this, QByteArrayLiteral("opacity"));
+    connect(animation, &QPropertyAnimation::finished, this, &QLineEditIconButton::onAnimationFinished);
+
     animation->setDuration(160);
     animation->setEndValue(endValue);
     animation->start(QAbstractAnimation::DeleteWhenStopped);
@@ -409,6 +447,16 @@ void QLineEditIconButton::updateCursor()
 }
 #endif // QT_CONFIG(toolbutton)
 
+#if QT_CONFIG(animation) && QT_CONFIG(toolbutton)
+static void displayWidgets(const QLineEditPrivate::SideWidgetEntryList &widgets, bool display)
+{
+    for (const auto &e : widgets) {
+        if (e.flags & QLineEditPrivate::SideWidgetFadeInWithText)
+            static_cast<QLineEditIconButton *>(e.widget)->animateShow(display);
+    }
+}
+#endif
+
 void QLineEditPrivate::_q_textChanged(const QString &text)
 {
     if (hasSideWidgets()) {
@@ -416,15 +464,9 @@ void QLineEditPrivate::_q_textChanged(const QString &text)
         if (!newTextSize || !lastTextSize) {
             lastTextSize = newTextSize;
 #if QT_CONFIG(animation) && QT_CONFIG(toolbutton)
-            const bool fadeIn = newTextSize > 0;
-            for (const SideWidgetEntry &e : leadingSideWidgets) {
-                if (e.flags & SideWidgetFadeInWithText)
-                   static_cast<QLineEditIconButton *>(e.widget)->animateShow(fadeIn);
-            }
-            for (const SideWidgetEntry &e : trailingSideWidgets) {
-                if (e.flags & SideWidgetFadeInWithText)
-                   static_cast<QLineEditIconButton *>(e.widget)->animateShow(fadeIn);
-            }
+            const bool display = newTextSize > 0;
+            displayWidgets(leadingSideWidgets, display);
+            displayWidgets(trailingSideWidgets, display);
 #endif
         }
     }
@@ -541,8 +583,15 @@ QWidget *QLineEditPrivate::addAction(QAction *newAction, QAction *before, QLineE
         QLineEditIconButton *toolButton = new QLineEditIconButton(q);
         toolButton->setIcon(newAction->icon());
         toolButton->setOpacity(lastTextSize > 0 || !(flags & SideWidgetFadeInWithText) ? 1 : 0);
-        if (flags & SideWidgetClearButton)
+        if (flags & SideWidgetClearButton) {
             QObject::connect(toolButton, SIGNAL(clicked()), q, SLOT(_q_clearButtonClicked()));
+
+#if QT_CONFIG(animation)
+            // The clear button is handled only by this widget. The button should be really
+            // shown/hidden in order to calculate size hints correctly.
+            toolButton->setHideWithText(true);
+#endif
+        }
         toolButton->setDefaultAction(newAction);
         w = toolButton;
 #else
@@ -606,33 +655,26 @@ void QLineEditPrivate::removeAction(QAction *action)
 #endif // QT_CONFIG(action)
 }
 
-static bool isSideWidgetVisible(const QLineEditPrivate::SideWidgetEntry &e)
+static int effectiveTextMargin(int defaultMargin, const QLineEditPrivate::SideWidgetEntryList &widgets,
+                               const QLineEditPrivate::SideWidgetParameters &parameters)
 {
-   return e.widget->isVisible();
+    if (widgets.empty())
+        return defaultMargin;
+
+    return defaultMargin + (parameters.margin + parameters.widgetWidth) *
+           int(std::count_if(widgets.begin(), widgets.end(),
+                             [](const QLineEditPrivate::SideWidgetEntry &e) {
+                                 return e.widget->isVisibleTo(e.widget->parentWidget()); }));
 }
 
 int QLineEditPrivate::effectiveLeftTextMargin() const
 {
-    int result = leftTextMargin;
-    if (!leftSideWidgetList().empty()) {
-        const SideWidgetParameters p = sideWidgetParameters();
-        result += (p.margin + p.widgetWidth)
-            * int(std::count_if(leftSideWidgetList().begin(), leftSideWidgetList().end(),
-                                isSideWidgetVisible));
-    }
-    return result;
+    return effectiveTextMargin(leftTextMargin, leftSideWidgetList(), sideWidgetParameters());
 }
 
 int QLineEditPrivate::effectiveRightTextMargin() const
 {
-    int result = rightTextMargin;
-    if (!rightSideWidgetList().empty()) {
-        const SideWidgetParameters p = sideWidgetParameters();
-        result += (p.margin + p.widgetWidth)
-            * int(std::count_if(rightSideWidgetList().begin(), rightSideWidgetList().end(),
-                                isSideWidgetVisible));
-    }
-    return result;
+    return effectiveTextMargin(rightTextMargin, rightSideWidgetList(), sideWidgetParameters());
 }
 
 
diff --git a/src/widgets/widgets/qlineedit_p.h b/src/widgets/widgets/qlineedit_p.h
index 7cd91dfc29..12a2f1ddfd 100644
--- a/src/widgets/widgets/qlineedit_p.h
+++ b/src/widgets/widgets/qlineedit_p.h
@@ -90,7 +90,10 @@ public:
     qreal opacity() const { return m_opacity; }
     void setOpacity(qreal value);
 #if QT_CONFIG(animation)
-    void animateShow(bool visible) { startOpacityAnimation(visible ? 1.0 : 0.0); }
+    void animateShow(bool visible);
+
+    bool shouldHideWithText() const;
+    void setHideWithText(bool hide);
 #endif
 
 protected:
@@ -100,6 +103,10 @@ protected:
 private slots:
     void updateCursor();
 
+#if QT_CONFIG(animation)
+    void onAnimationFinished();
+#endif
+
 private:
 #if QT_CONFIG(animation)
     void startOpacityAnimation(qreal endValue);
@@ -107,6 +114,12 @@ private:
     QLineEditPrivate *lineEditPrivate() const;
 
     qreal m_opacity;
+
+#if QT_CONFIG(animation)
+    bool m_hideWithText = false;
+    bool m_wasHidden = false;
+#endif
+
 };
 #endif // QT_CONFIG(toolbutton)