Add ToolTip support for Qt WebEngine (QML)

[ChangeLog][QtWebEngineQML][QQuickWebEngineView] ToolTip
(HTML global title attribute) are now handled.

Task-numner: QTBUG-54108
Change-Id: I78cc3c1e934a822d6399ebd35c8c7895fbdf5749
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@qt.io>

6 files changed, 167 insertions, 3 deletions

diff --git a/src/webengine/api/qquickwebengineview.cpp b/src/webengine/api/qquickwebengineview.cpp
index b660b06be..983e8c30e 100644
--- a/src/webengine/api/qquickwebengineview.cpp
+++ b/src/webengine/api/qquickwebengineview.cpp
@@ -1106,6 +1106,11 @@ bool QQuickWebEngineViewPrivate::isEnabled() const
     return q->isEnabled();
 }
 
+void QQuickWebEngineViewPrivate::setToolTip(const QString &toolTipText)
+{
+    ui()->showToolTip(toolTipText);
+}
+
 bool QQuickWebEngineView::isLoading() const
 {
     Q_D(const QQuickWebEngineView);
diff --git a/src/webengine/api/qquickwebengineview_p_p.h b/src/webengine/api/qquickwebengineview_p_p.h
index e82aebbd4..45332ddb1 100644
--- a/src/webengine/api/qquickwebengineview_p_p.h
+++ b/src/webengine/api/qquickwebengineview_p_p.h
@@ -188,7 +188,7 @@ public:
     void startDragging(const content::DropData &dropData, Qt::DropActions allowedActions,
                        const QPixmap &pixmap, const QPoint &offset) Q_DECL_OVERRIDE;
     virtual bool isEnabled() const Q_DECL_OVERRIDE;
-    virtual void setToolTip(const QString &toolTipText) Q_DECL_OVERRIDE { Q_UNUSED(toolTipText); }
+    virtual void setToolTip(const QString &toolTipText) Q_DECL_OVERRIDE;
     const QObject *holdingQObject() const Q_DECL_OVERRIDE;
 
     virtual QSharedPointer<QtWebEngineCore::BrowserContextAdapter> browserContextAdapter() Q_DECL_OVERRIDE;
diff --git a/src/webengine/ui/ToolTip.qml b/src/webengine/ui/ToolTip.qml
new file mode 100644
index 000000000..96033e8f1
--- /dev/null
+++ b/src/webengine/ui/ToolTip.qml
@@ -0,0 +1,91 @@
+/****************************************************************************
+**
+** Copyright (C) 2016 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+import QtQuick 2.5
+
+Item {
+    id: toolTipContainer
+    z: 9999
+    width: content.width
+    height: content.height
+    visible: false
+
+    property alias text: toolTip.text
+    property int delayTimerInterval: 1000
+    property int hideTimerInterval: 1500
+
+    Timer {
+        id: delayTimer
+        interval: delayTimerInterval
+        onTriggered: {
+            toolTipContainer.visible = true
+            hideTimer.start()
+        }
+    }
+
+    Timer {
+        id: hideTimer
+        interval: hideTimerInterval
+        onTriggered: toolTipContainer.visible = false
+    }
+
+    Rectangle {
+        id: content
+        color: "#f8eabf"
+        border.color: "black"
+        anchors.centerIn: parent
+        width: toolTip.contentWidth + 10
+        height: toolTip.contentHeight + 10
+        radius: 3
+
+       Text {
+            id: toolTip
+            anchors {fill: parent; margins: 5}
+            wrapMode: Text.WrapAnywhere
+        }
+    }
+
+    function open() {
+        delayTimer.start();
+    }
+
+    function hide() {
+        hideTimer.start();
+    }
+}
diff --git a/src/webengine/ui/ui.pro b/src/webengine/ui/ui.pro
index 249d7dcfd..60dab61d6 100644
--- a/src/webengine/ui/ui.pro
+++ b/src/webengine/ui/ui.pro
@@ -14,6 +14,7 @@ QML_FILES += \
     MenuItem.qml \
     MenuSeparator.qml \
     # Message Bubble
-    MessageBubble.qml
+    MessageBubble.qml \
+    ToolTip.qml
 
 load(qml_module)
diff --git a/src/webengine/ui_delegates_manager.cpp b/src/webengine/ui_delegates_manager.cpp
index 6ff12b53f..769a30016 100644
--- a/src/webengine/ui_delegates_manager.cpp
+++ b/src/webengine/ui_delegates_manager.cpp
@@ -50,6 +50,10 @@
 #include <QQmlContext>
 #include <QQmlEngine>
 #include <QQmlProperty>
+#include <QCursor>
+#include <QList>
+#include <QScreen>
+#include <QGuiApplication>
 
 // Uncomment for QML debugging
 //#define UI_DELEGATES_DEBUG
@@ -93,6 +97,31 @@ static QString getUIDelegatesImportDir(QQmlEngine *engine) {
     return importDir;
 }
 
+static QPoint calculateToolTipPosition(QPoint &position, QSize &toolTip) {
+    QRect screen;
+    QList<QScreen *> screens = QGuiApplication::screens();
+    Q_FOREACH (const QScreen *src, screens)
+        if (src->availableGeometry().contains(position))
+            screen = src->availableGeometry();
+
+    position += QPoint(2, 16);
+
+    if (position.x() + toolTip.width() > screen.x() + screen.width())
+        position.rx() -= 4 + toolTip.width();
+    if (position.y() + toolTip.height() > screen.y() + screen.height())
+        position.ry() -= 24 + toolTip.height();
+    if (position.y() < screen.y())
+        position.setY(screen.y());
+    if (position.x() + toolTip.width() > screen.x() + screen.width())
+        position.setX(screen.x() + screen.width() - toolTip.width());
+    if (position.x() < screen.x())
+        position.setX(screen.x());
+    if (position.y() + toolTip.height() > screen.y() + screen.height())
+        position.setY(screen.y() + screen.height() - toolTip.height());
+
+    return position;
+}
+
 const char *defaultPropertyName(QObject *obj)
 {
     const QMetaObject *metaObject = obj->metaObject();
@@ -116,6 +145,7 @@ MenuItemHandler::MenuItemHandler(QObject *parent)
 UIDelegatesManager::UIDelegatesManager(QQuickWebEngineView *view)
     : m_view(view)
     , m_messageBubbleItem(0)
+    , m_toolTip(nullptr)
     FOR_EACH_COMPONENT_TYPE(COMPONENT_MEMBER_INIT, NO_SEPARATOR)
 {
 }
@@ -493,4 +523,38 @@ void UIDelegatesManager::moveMessageBubble(const QRect &anchor)
     QQmlProperty(m_messageBubbleItem.data(), QStringLiteral("y")).write(anchor.y() + anchor.size().height());
 }
 
+void UIDelegatesManager::showToolTip(const QString &text)
+{
+    if (!ensureComponentLoaded(ToolTip))
+        return;
+
+    if (text.isEmpty()) {
+        m_toolTip.reset();
+        return;
+    }
+
+    if (!m_toolTip.isNull())
+        return;
+
+    QQmlContext *context = qmlContext(m_view);
+    m_toolTip.reset(toolTipComponent->beginCreate(context));
+    if (QQuickItem *item = qobject_cast<QQuickItem *>(m_toolTip.data()))
+        item->setParentItem(m_view);
+    m_toolTip->setParent(m_view);
+    toolTipComponent->completeCreate();
+
+    QQmlProperty(m_toolTip.data(), QStringLiteral("text")).write(text);
+
+    int height = QQmlProperty(m_toolTip.data(), QStringLiteral("height")).read().toInt();
+    int width = QQmlProperty(m_toolTip.data(), QStringLiteral("width")).read().toInt();
+    QSize toolTipSize(width, height);
+    QPoint position = m_view->cursor().pos();
+    position = m_view->mapFromGlobal(calculateToolTipPosition(position, toolTipSize)).toPoint();
+
+    QQmlProperty(m_toolTip.data(), QStringLiteral("x")).write(position.x());
+    QQmlProperty(m_toolTip.data(), QStringLiteral("y")).write(position.y());
+
+    QMetaObject::invokeMethod(m_toolTip.data(), "open");
+}
+
 } // namespace QtWebEngineCore
diff --git a/src/webengine/ui_delegates_manager.h b/src/webengine/ui_delegates_manager.h
index b63aa91f1..43d1e6985 100644
--- a/src/webengine/ui_delegates_manager.h
+++ b/src/webengine/ui_delegates_manager.h
@@ -59,7 +59,8 @@
     F(PromptDialog, promptDialog) SEPARATOR \
     F(FilePicker, filePicker) SEPARATOR \
     F(MessageBubble, messageBubble) SEPARATOR \
-    F(AuthenticationDialog, authenticationDialog) SEPARATOR
+    F(AuthenticationDialog, authenticationDialog) SEPARATOR \
+    F(ToolTip, toolTip) SEPARATOR \
 
 #define COMMA_SEPARATOR ,
 #define SEMICOLON_SEPARATOR ;
@@ -115,12 +116,14 @@ public:
     void showMessageBubble(const QRect &anchor, const QString &mainText, const QString &subText);
     void hideMessageBubble();
     void moveMessageBubble(const QRect &anchor);
+    void showToolTip(const QString &text);
 
 private:
     bool ensureComponentLoaded(ComponentType);
 
     QQuickWebEngineView *m_view;
     QScopedPointer<QQuickItem> m_messageBubbleItem;
+    QScopedPointer<QObject> m_toolTip;
 
     FOR_EACH_COMPONENT_TYPE(MEMBER_DECLARATION, SEMICOLON_SEPARATOR)