Pave the way for our UI delegation strategy.

Starting with the context Menus for QtQuick.
Add default UI delegates as a subproject. We allow ourselves to use
Qt Quick Controls there for in order to get a nice "out of the box"
experience for things like context menus, dialogs, etc while leaving
the door open for system embedders to override this.

Opting out of the deployment of these QML files is still very primitive
but can be done by passing WEBENGINE_CONFIG+=no_ui_delegates at qmake
time.

Customization of context menus could be done via a qml component, which
is probably best kept in experimental for now while we address its
shortcomings.

Change-Id: I0705b20d5ddd3bb010f9371b65a181c6b02a03e1
Reviewed-by: Jocelyn Turcotte <jocelyn.turcotte@digia.com>

2 files changed, 102 insertions, 3 deletions

diff --git a/src/webengine/api/qquickwebengineview.cpp b/src/webengine/api/qquickwebengineview.cpp
index ac2dc681e..1dcc2acd0 100644
--- a/src/webengine/api/qquickwebengineview.cpp
+++ b/src/webengine/api/qquickwebengineview.cpp
@@ -44,20 +44,29 @@
 
 #include "net/base/net_errors.h"
 #include "qquickwebengineloadrequest_p.h"
+#include "render_widget_host_view_qt_delegate_quick.h"
+#include "ui_delegates_manager.h"
 #include "web_contents_adapter.h"
 #include "web_engine_error.h"
-#include "render_widget_host_view_qt_delegate_quick.h"
 
+#include <QQmlEngine>
+#include <QQmlComponent>
+#include <QQmlContext>
+#include <QQmlProperty>
 #include <QScreen>
+#include <QStringBuilder>
 #include <QUrl>
 #include <QQmlEngine>
 
+#include <private/qqmlmetatype_p.h>
+
 QT_BEGIN_NAMESPACE
 
 QQuickWebEngineViewPrivate::QQuickWebEngineViewPrivate()
     : adapter(new WebContentsAdapter(qApp->property("QQuickWebEngineView_DisableHardwareAcceleration").toBool() ? SoftwareRenderingMode : HardwareAccelerationMode))
     , e(new QQuickWebEngineViewExperimental(this))
     , v(new QQuickWebEngineViewport(this))
+    , contextMenuExtraItems(0)
     , loadProgress(0)
     , inspectable(false)
     , m_isLoading(false)
@@ -94,6 +103,14 @@ QQuickWebEngineViewport *QQuickWebEngineViewPrivate::viewport() const
     return v.data();
 }
 
+UIDelegatesManager *QQuickWebEngineViewPrivate::ui()
+{
+    Q_Q(QQuickWebEngineView);
+    if (m_uIDelegatesManager.isNull())
+        m_uIDelegatesManager.reset(new UIDelegatesManager(q));
+    return m_uIDelegatesManager.data();
+}
+
 RenderWidgetHostViewQtDelegate *QQuickWebEngineViewPrivate::CreateRenderWidgetHostViewQtDelegate(RenderWidgetHostViewQtDelegateClient *client, RenderingMode mode)
 {
 #if (QT_VERSION >= QT_VERSION_CHECK(5, 2, 0))
@@ -103,6 +120,63 @@ RenderWidgetHostViewQtDelegate *QQuickWebEngineViewPrivate::CreateRenderWidgetHo
     return new RenderWidgetHostViewQtDelegateQuickPainted(client);
 }
 
+bool QQuickWebEngineViewPrivate::contextMenuRequested(const WebEngineContextMenuData &data)
+{
+    Q_Q(QQuickWebEngineView);
+
+    QObject *menu = ui()->addMenu(0, QString(), data.pos);
+    if (!menu)
+        return false;
+
+    // Populate our menu
+    MenuItemHandler *item = 0;
+
+    if (data.selectedText.isEmpty()) {
+        item = new MenuItemHandler(menu);
+        QObject::connect(item, &MenuItemHandler::triggered, q, &QQuickWebEngineView::goBack);
+        ui()->addMenuItem(item, QObject::tr("Back"), QStringLiteral("go-previous"), q->canGoBack());
+
+        item = new MenuItemHandler(menu);
+        QObject::connect(item, &MenuItemHandler::triggered, q, &QQuickWebEngineView::goForward);
+        ui()->addMenuItem(item, QObject::tr("Forward"), QStringLiteral("go-next"), q->canGoForward());
+
+        item = new MenuItemHandler(menu);
+        QObject::connect(item, &MenuItemHandler::triggered, q, &QQuickWebEngineView::reload);
+        ui()->addMenuItem(item, QObject::tr("Reload"), QStringLiteral("view-refresh"));
+    } else {
+        item = new CopyMenuItem(menu, data.selectedText);
+        ui()->addMenuItem(item, QObject::tr("Copy..."));
+    }
+
+    if (!data.linkText.isEmpty() && data.linkUrl.isValid()) {
+        item = new NavigateMenuItem(menu, adapter, data.linkUrl);
+        ui()->addMenuItem(item, QObject::tr("Navigate to..."));
+        item = new CopyMenuItem(menu, data.linkUrl.toString());
+        ui()->addMenuItem(item, QObject::tr("Copy link address"));
+    }
+
+    // FIXME: expose the context menu data as an attached property to make this more useful
+    if (contextMenuExtraItems) {
+        ui()->addMenuSeparator(menu);
+        if (QObject* menuExtras = contextMenuExtraItems->create(ui()->creationContextForComponent(contextMenuExtraItems))) {
+            menuExtras->setParent(menu);
+            QQmlListReference entries(menu, QQmlMetaType::defaultProperty(menu).name(), qmlEngine(q));
+            if (entries.isValid())
+                entries.append(menuExtras);
+        }
+    }
+
+    // Now fire the popup() method on the top level menu
+    QMetaObject::invokeMethod(menu, "popup");
+    return true;
+}
+
+bool QQuickWebEngineViewPrivate::javascriptDialog(JavascriptDialogType type, const QString &message, const QString &defaultValue, QString *result)
+{
+    Q_UNUSED(message); Q_UNUSED(defaultValue); Q_UNUSED(result);
+    return false;
+}
+
 void QQuickWebEngineViewPrivate::titleChanged(const QString &title)
 {
     Q_Q(QQuickWebEngineView);
@@ -338,6 +412,19 @@ void QQuickWebEngineView::setInspectable(bool enable)
     d->adapter->enableInspector(enable);
 }
 
+void QQuickWebEngineViewExperimental::setExtraContextMenuEntriesComponent(QQmlComponent *contextMenuExtras)
+{
+    if (d_ptr->contextMenuExtraItems == contextMenuExtras)
+        return;
+    d_ptr->contextMenuExtraItems = contextMenuExtras;
+    emit extraContextMenuEntriesComponentChanged();
+}
+
+QQmlComponent *QQuickWebEngineViewExperimental::extraContextMenuEntriesComponent() const
+{
+    return d_ptr->contextMenuExtraItems;
+}
+
 void QQuickWebEngineView::geometryChanged(const QRectF &newGeometry, const QRectF &oldGeometry)
 {
     QQuickItem::geometryChanged(newGeometry, oldGeometry);
diff --git a/src/webengine/api/qquickwebengineview_p_p.h b/src/webengine/api/qquickwebengineview_p_p.h
index 110a1b9b6..67337baeb 100644
--- a/src/webengine/api/qquickwebengineview_p_p.h
+++ b/src/webengine/api/qquickwebengineview_p_p.h
@@ -47,13 +47,17 @@
 
 #include <QScopedPointer>
 #include <QSharedData>
+#include <QString>
 #include <QtCore/qcompilerdetection.h>
 #include <QtQuick/private/qquickitem_p.h>
 
 class WebContentsAdapter;
+class UIDelegatesManager;
 
 QT_BEGIN_NAMESPACE
 class QQuickWebEngineView;
+class QQmlComponent;
+class QQmlContext;
 
 class Q_WEBENGINE_PRIVATE_EXPORT QQuickWebEngineViewport : public QObject {
     Q_OBJECT
@@ -88,12 +92,17 @@ private:
 class Q_WEBENGINE_PRIVATE_EXPORT QQuickWebEngineViewExperimental : public QObject {
     Q_OBJECT
     Q_PROPERTY(QQuickWebEngineViewport *viewport READ viewport)
+    Q_PROPERTY(QQmlComponent *extraContextMenuEntriesComponent READ extraContextMenuEntriesComponent WRITE setExtraContextMenuEntriesComponent NOTIFY extraContextMenuEntriesComponentChanged)
+
 public:
     QQuickWebEngineViewport *viewport() const;
     Q_INVOKABLE void adoptHandle(QQuickWebEngineViewHandle *viewHandle);
+    void setExtraContextMenuEntriesComponent(QQmlComponent *);
+    QQmlComponent *extraContextMenuEntriesComponent() const;
 
 Q_SIGNALS:
     void createWindow(const QJSValue &newViewHandle, const QString &newViewDisposition);
+    void extraContextMenuEntriesComponentChanged();
 
 private:
     QQuickWebEngineViewExperimental(QQuickWebEngineViewPrivate* viewPrivate);
@@ -112,6 +121,7 @@ public:
 
     QQuickWebEngineViewExperimental *experimental() const;
     QQuickWebEngineViewport *viewport() const;
+    UIDelegatesManager *ui();
 
     virtual RenderWidgetHostViewQtDelegate* CreateRenderWidgetHostViewQtDelegate(RenderWidgetHostViewQtDelegateClient *client, RenderingMode) Q_DECL_OVERRIDE;
     virtual void titleChanged(const QString&) Q_DECL_OVERRIDE;
@@ -125,8 +135,8 @@ public:
     virtual void focusContainer() Q_DECL_OVERRIDE;
     virtual void adoptNewWindow(WebContentsAdapter *newWebContents, WindowOpenDisposition disposition, const QRect &) Q_DECL_OVERRIDE;
     virtual void close() Q_DECL_OVERRIDE;
-    virtual bool contextMenuRequested(const WebEngineContextMenuData &) Q_DECL_OVERRIDE { return false;}
-    virtual bool javascriptDialog(JavascriptDialogType type, const QString &message, const QString &defaultValue = QString(), QString *result = 0) Q_DECL_OVERRIDE { return false; }
+    virtual bool contextMenuRequested(const WebEngineContextMenuData &) Q_DECL_OVERRIDE;
+    virtual bool javascriptDialog(JavascriptDialogType, const QString &message, const QString &defaultValue = QString(), QString *result = 0) Q_DECL_OVERRIDE { Q_UNUSED(message); Q_UNUSED(defaultValue); Q_UNUSED(result); return false; }
     virtual void runFileChooser(FileChooserMode, const QString &defaultFileName, const QStringList &acceptedMimeTypes) { Q_UNUSED(defaultFileName); Q_UNUSED(acceptedMimeTypes);}
 
     void setDevicePixelRatio(qreal);
@@ -134,6 +144,7 @@ public:
     QExplicitlySharedDataPointer<WebContentsAdapter> adapter;
     QScopedPointer<QQuickWebEngineViewExperimental> e;
     QScopedPointer<QQuickWebEngineViewport> v;
+    QQmlComponent *contextMenuExtraItems;
     QUrl icon;
     int loadProgress;
     bool inspectable;
@@ -141,6 +152,7 @@ public:
     qreal devicePixelRatio;
 
 private:
+    QScopedPointer<UIDelegatesManager> m_uIDelegatesManager;
     qreal m_dpiScale;
 };