Support HTML5 form validation feature

HTML5 provides built-in form validation that is supported by chromium.
The form validation messages should be shown by the browser therefore
new MessageBubble UI element has been added to Quick and Widget
implementations.
This patch implements chromium's form validation events and shows the
messages in a MessageBubble.

Change-Id: I0c8f4f102823117e2bfb16ff8a4c503635491939
Reviewed-by: Andras Becsi <andras.becsi@theqtcompany.com>

6 files changed, 340 insertions, 0 deletions

diff --git a/src/webenginewidgets/api/qwebenginepage.cpp b/src/webenginewidgets/api/qwebenginepage.cpp
index 7eab1dc71..65a0a5bed 100644
--- a/src/webenginewidgets/api/qwebenginepage.cpp
+++ b/src/webenginewidgets/api/qwebenginepage.cpp
@@ -38,6 +38,10 @@
 #include "web_contents_adapter.h"
 #include "web_engine_settings.h"
 
+#ifdef QT_UI_DELEGATES
+#include "ui/messagebubblewidget_p.h"
+#endif
+
 #include <QAction>
 #include <QApplication>
 #include <QAuthenticator>
@@ -778,6 +782,27 @@ void QWebEnginePagePrivate::javaScriptConsoleMessage(JavaScriptConsoleMessageLev
     q->javaScriptConsoleMessage(static_cast<QWebEnginePage::JavaScriptConsoleMessageLevel>(level), message, lineNumber, sourceID);
 }
 
+void QWebEnginePagePrivate::showValidationMessage(const QRect &anchor, const QString &mainText, const QString &subText)
+{
+#ifdef QT_UI_DELEGATES
+    QtWebEngineWidgetUI::MessageBubbleWidget::showBubble(view, anchor, mainText, subText);
+#endif
+}
+
+void QWebEnginePagePrivate::hideValidationMessage()
+{
+#ifdef QT_UI_DELEGATES
+    QtWebEngineWidgetUI::MessageBubbleWidget::hideBubble();
+#endif
+}
+
+void QWebEnginePagePrivate::moveValidationMessage(const QRect &anchor)
+{
+#ifdef QT_UI_DELEGATES
+    QtWebEngineWidgetUI::MessageBubbleWidget::moveBubble(view, anchor);
+#endif
+}
+
 namespace {
 class SaveToClipboardFunctor
 {
diff --git a/src/webenginewidgets/api/qwebenginepage_p.h b/src/webenginewidgets/api/qwebenginepage_p.h
index 087137a78..8f45ecddf 100644
--- a/src/webenginewidgets/api/qwebenginepage_p.h
+++ b/src/webenginewidgets/api/qwebenginepage_p.h
@@ -147,6 +147,9 @@ public:
 #endif // QT_NO_ACCESSIBILITY
     virtual QtWebEngineCore::WebEngineSettings *webEngineSettings() const Q_DECL_OVERRIDE;
     virtual void allowCertificateError(const QSharedPointer<CertificateErrorController> &controller) Q_DECL_OVERRIDE;
+    virtual void showValidationMessage(const QRect &anchor, const QString &mainText, const QString &subText) Q_DECL_OVERRIDE;
+    virtual void hideValidationMessage() Q_DECL_OVERRIDE;
+    virtual void moveValidationMessage(const QRect &anchor) Q_DECL_OVERRIDE;
 
     virtual QtWebEngineCore::BrowserContextAdapter *browserContextAdapter() Q_DECL_OVERRIDE;
 
diff --git a/src/webenginewidgets/api/qwebengineview.cpp b/src/webenginewidgets/api/qwebengineview.cpp
index 039e18a16..a4a8dd760 100644
--- a/src/webenginewidgets/api/qwebengineview.cpp
+++ b/src/webenginewidgets/api/qwebengineview.cpp
@@ -40,6 +40,10 @@
 #include "qwebenginepage_p.h"
 #include "web_contents_adapter.h"
 
+#ifdef QT_UI_DELEGATES
+#include "ui/messagebubblewidget_p.h"
+#endif
+
 #include <QAction>
 #include <QMenu>
 #include <QContextMenuEvent>
@@ -118,6 +122,10 @@ QWebEngineView::~QWebEngineView()
 {
     Q_D(QWebEngineView);
     QWebEngineViewPrivate::bind(0, d->page);
+
+#ifdef QT_UI_DELEGATES
+    QtWebEngineWidgetUI::MessageBubbleWidget::hideBubble();
+#endif
 }
 
 QWebEnginePage* QWebEngineView::page() const
diff --git a/src/webenginewidgets/ui/messagebubblewidget.cpp b/src/webenginewidgets/ui/messagebubblewidget.cpp
new file mode 100644
index 000000000..3465f4218
--- /dev/null
+++ b/src/webenginewidgets/ui/messagebubblewidget.cpp
@@ -0,0 +1,221 @@
+/****************************************************************************
+**
+** Copyright (C) 2015 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** 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 Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/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.LGPLv3 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.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 later as published by the Free
+** Software Foundation and appearing in the file LICENSE.GPL included in
+** the packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 2.0 requirements will be
+** met: http://www.gnu.org/licenses/gpl-2.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "messagebubblewidget_p.h"
+
+#include "api/qwebengineview.h"
+
+#include <QBitmap>
+#include <QHBoxLayout>
+#include <QIcon>
+#include <QLabel>
+#include <QStyle>
+
+namespace QtWebEngineWidgetUI {
+
+Q_GLOBAL_STATIC(MessageBubbleWidget, bubbleInstance)
+
+void MessageBubbleWidget::showBubble(QWebEngineView *view, const QRect &anchor, const QString &mainText, const QString &subText)
+{
+    hideBubble();
+    if (mainText.isEmpty())
+        return;
+
+    bubbleInstance->createBubble(anchor.size().width(), mainText, subText);
+    bubbleInstance->moveToAnchor(view, anchor);
+}
+
+void MessageBubbleWidget::hideBubble()
+{
+    bubbleInstance->hide();
+}
+
+void MessageBubbleWidget::moveBubble(QWebEngineView *view, const QRect &anchor)
+{
+    bubbleInstance->moveToAnchor(view, anchor);
+}
+
+MessageBubbleWidget::MessageBubbleWidget()
+   : QWidget(0, Qt::ToolTip)
+   , m_mainLabel(new QLabel)
+   , m_subLabel(new QLabel)
+{
+    QHBoxLayout *hLayout = new QHBoxLayout;
+    hLayout->setAlignment(Qt::AlignTop);
+    hLayout->setSizeConstraint(QLayout::SetFixedSize);
+    hLayout->setMargin(3);
+
+    const int iconSize = 18;
+    QIcon si = style()->standardIcon(QStyle::SP_MessageBoxWarning);
+
+    if (!si.isNull()) {
+        QLabel *iconLabel = new QLabel(this);
+        iconLabel->setPixmap(si.pixmap(iconSize, iconSize));
+        iconLabel->setSizePolicy(QSizePolicy::Fixed, QSizePolicy::Fixed);
+        iconLabel->setMargin(2);
+        hLayout->addWidget(iconLabel, 0, Qt::AlignTop);
+    }
+
+    QVBoxLayout *vLayout = new QVBoxLayout;
+
+    m_mainLabel->installEventFilter(this);
+    m_mainLabel->setWordWrap(true);
+    m_mainLabel->setTextFormat(Qt::PlainText);
+    m_mainLabel->setAlignment(Qt::AlignTop | Qt::AlignLeft);
+    vLayout->addWidget(m_mainLabel.data());
+
+    QFont mainFont = m_mainLabel->font();
+    mainFont.setPointSize(mainFont.pointSize() + 4);
+    m_mainLabel->setFont(mainFont);
+
+    m_subLabel->installEventFilter(this);
+    m_subLabel->setWordWrap(true);
+    m_subLabel->setTextFormat(Qt::PlainText);
+    m_subLabel->setAlignment(Qt::AlignBottom | Qt::AlignLeft);
+    vLayout->addWidget(m_subLabel.data());
+
+    hLayout->addLayout(vLayout);
+    setLayout(hLayout);
+
+    QPalette pal = palette();
+    pal.setColor(QPalette::Window, QColor(0xff, 0xff, 0xe1));
+    pal.setColor(QPalette::WindowText, Qt::black);
+    setPalette(pal);
+}
+
+MessageBubbleWidget::~MessageBubbleWidget()
+{
+}
+
+void MessageBubbleWidget::paintEvent(QPaintEvent *)
+{
+    QPainter painter(this);
+    painter.drawPixmap(rect(), m_pixmap);
+}
+
+void MessageBubbleWidget::createBubble(const int maxWidth, const QString &mainText, const QString &subText)
+{
+    m_mainLabel->setText(mainText);
+    m_mainLabel->setMaximumWidth(maxWidth);
+
+    m_subLabel->setText(subText);
+    m_subLabel->setMaximumWidth(maxWidth);
+    m_subLabel->setVisible(!subText.isEmpty());
+
+    int border = 1;
+    int arrowHeight = 18;
+    bool roundedCorners = true;
+
+#if defined(QT_NO_XSHAPE) && defined(Q_WS_X11)
+    // XShape is required for setting the mask, so we just
+    // draw an ugly square when its not available
+    arrowHeight = 0;
+    roundedCorners = false;
+#endif
+
+    setContentsMargins(border + 3,  border + arrowHeight + 2, border + 3, border + 2);
+    show(); // The widget should be visible for updateGeometry()
+    updateGeometry();
+    m_pixmap = QPixmap(sizeHint());
+
+    QPainterPath path = drawBoxPath(QPoint(0, arrowHeight), border, roundedCorners);
+
+    // Draw border and set background
+    QPainter painter(&m_pixmap);
+    painter.setPen(QPen(palette().color(QPalette::Window).darker(160), border));
+    painter.setBrush(palette().color(QPalette::Window));
+    painter.drawPath(path);
+}
+
+void MessageBubbleWidget::moveToAnchor(QWebEngineView *view, const QRect &anchor)
+{
+    QPoint topLeft = view->mapToGlobal(anchor.topLeft());
+    move(topLeft.x(), topLeft.y() + anchor.height());
+}
+
+QPainterPath MessageBubbleWidget::drawBoxPath(const QPoint &pos, int border, bool roundedCorners)
+{
+    const int arrowHeight = pos.y();
+    const int arrowOffset = 18;
+    const int arrowWidth = 18;
+
+    const int cornerRadius = roundedCorners ? 7 : 0;
+
+    const int messageBoxLeft = pos.x();
+    const int messageBoxTop = arrowHeight;
+    const int messageBoxRight = m_pixmap.width() - 1;
+    const int messageBoxBottom = m_pixmap.height() - 1;
+
+    QPainterPath path;
+    path.moveTo(messageBoxLeft + cornerRadius, messageBoxTop);
+
+    if (arrowHeight) {
+        path.lineTo(messageBoxLeft + arrowOffset, messageBoxTop);
+        path.lineTo(messageBoxLeft + arrowOffset, messageBoxTop - arrowHeight);
+        path.lineTo(messageBoxLeft + arrowOffset + arrowWidth, messageBoxTop);
+    }
+
+    if (roundedCorners) {
+        path.lineTo(messageBoxRight - cornerRadius, messageBoxTop);
+        path.quadTo(messageBoxRight, messageBoxTop, messageBoxRight, messageBoxTop + cornerRadius);
+        path.lineTo(messageBoxRight, messageBoxBottom - cornerRadius);
+        path.quadTo(messageBoxRight, messageBoxBottom, messageBoxRight - cornerRadius, messageBoxBottom);
+        path.lineTo(messageBoxLeft + cornerRadius, messageBoxBottom);
+        path.quadTo(messageBoxLeft, messageBoxBottom, messageBoxLeft, messageBoxBottom - cornerRadius);
+        path.lineTo(messageBoxLeft, messageBoxTop + cornerRadius);
+        path.quadTo(messageBoxLeft, messageBoxTop, messageBoxLeft + cornerRadius, messageBoxTop);
+    } else {
+        path.lineTo(messageBoxRight, messageBoxTop);
+        path.lineTo(messageBoxRight, messageBoxBottom);
+        path.lineTo(messageBoxLeft, messageBoxBottom);
+        path.moveTo(messageBoxLeft, messageBoxTop);
+    }
+
+    // Set mask
+    if (arrowHeight || roundedCorners) {
+        QBitmap bitmap = QBitmap(sizeHint());
+        bitmap.fill(Qt::color0);
+        QPainter painter(&bitmap);
+        painter.setPen(QPen(Qt::color1, border));
+        painter.setBrush(QBrush(Qt::color1));
+        painter.drawPath(path);
+        setMask(bitmap);
+    }
+
+    return path;
+}
+
+} // namespace QtWebEngineWidgetUI
diff --git a/src/webenginewidgets/ui/messagebubblewidget_p.h b/src/webenginewidgets/ui/messagebubblewidget_p.h
new file mode 100644
index 000000000..7b7a9e309
--- /dev/null
+++ b/src/webenginewidgets/ui/messagebubblewidget_p.h
@@ -0,0 +1,77 @@
+/****************************************************************************
+**
+** Copyright (C) 2015 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** 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 Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/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.LGPLv3 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.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 later as published by the Free
+** Software Foundation and appearing in the file LICENSE.GPL included in
+** the packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 2.0 requirements will be
+** met: http://www.gnu.org/licenses/gpl-2.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef MESSAGEBUBBLEWIDGET_P_H
+#define MESSAGEBUBBLEWIDGET_P_H
+
+#include <QWidget>
+#include <QPainterPath>
+
+QT_BEGIN_NAMESPACE
+class QLabel;
+class QWebEngineView;
+QT_END_NAMESPACE
+
+namespace QtWebEngineWidgetUI {
+
+class MessageBubbleWidget : public QWidget
+{
+    Q_OBJECT
+public:
+    MessageBubbleWidget();
+    ~MessageBubbleWidget();
+
+    static void showBubble(QWebEngineView *view, const QRect &anchor, const QString &mainText, const QString &subText = QString());
+    static void hideBubble();
+    static void moveBubble(QWebEngineView *view, const QRect &anchor);
+
+protected:
+    void paintEvent(QPaintEvent *) Q_DECL_OVERRIDE;
+
+private:
+    void createBubble(const int maxWidth, const QString &mainText, const QString &subText);
+    void moveToAnchor(QWebEngineView *view, const QRect &anchor);
+
+    QPainterPath drawBoxPath(const QPoint &pos, int border, bool roundedCorners);
+
+    QScopedPointer<QLabel> m_mainLabel;
+    QScopedPointer<QLabel> m_subLabel;
+    QPixmap m_pixmap;
+};
+
+} // namespace QtWebEngineWidgetUI
+
+#endif // MESSAGEBUBBLEWIDGET_P_H
diff --git a/src/webenginewidgets/webenginewidgets.pro b/src/webenginewidgets/webenginewidgets.pro
index 02e687c7c..1f7974bd2 100644
--- a/src/webenginewidgets/webenginewidgets.pro
+++ b/src/webenginewidgets/webenginewidgets.pro
@@ -45,4 +45,10 @@ HEADERS = \
         api/qwebengineview_p.h \
         render_widget_host_view_qt_delegate_widget.h
 
+!contains(WEBENGINE_CONFIG, no_ui_delegates) {
+    SOURCES += ui/messagebubblewidget.cpp
+    HEADERS += ui/messagebubblewidget_p.h
+    DEFINES += QT_UI_DELEGATES
+}
+
 load(qt_module)