Dialogs: implementation prop renamed to contentItem; API cleanup

- contentItem is a common name for an item inside something such as a
window or a flickable.  We now consider it adequate API that you can
directly set this to some item which you want to fill the whole dialog
instead of adding an item as a child of the default property and being
subject to the dialog's margins and space reservation for buttons.
- contentItem MUST be an Item.  Allowing the old "implementation"
property to alternatively be a ready-made Window was just a
hypothetical use case, but if anyone made use of that, then it would
be a problem to have that kind of dialog on a GUI that cannot have
windows (such as Android or EGLFS). So there's no point in having
the possibility as long as we cannot emulate windows as items.
- standardButtonsRightModel and standardButtonsLeftModel are
implementation details so they should not be exposed as properties
which Creator can discover; users shouldn't depend on them.

Task-number: QTBUG-38056
Change-Id: Iefa3def314353495cfe8d1ef9f775a8e46d5bcf4
Reviewed-by: J-P Nurmi <jpnurmi@digia.com>

9 files changed, 94 insertions, 105 deletions

diff --git a/src/dialogs/DefaultDialogWrapper.qml b/src/dialogs/DefaultDialogWrapper.qml
index 0771bdb9..9f295914 100644
--- a/src/dialogs/DefaultDialogWrapper.qml
+++ b/src/dialogs/DefaultDialogWrapper.qml
@@ -47,19 +47,19 @@ import "qml"
 
 AbstractDialog {
     id: root
-    default property alias data: contentItem.data
+    default property alias data: defaultContentItem.data
 
     Rectangle {
         id: content
         property real spacing: 6
         property real outerSpacing: 12
         property real buttonsRowImplicitWidth: minimumWidth
-        property bool buttonsInSingleRow: contentItem.width >= buttonsRowImplicitWidth
+        property bool buttonsInSingleRow: defaultContentItem.width >= buttonsRowImplicitWidth
         property real minimumHeight: implicitHeight
         property real minimumWidth: Screen.pixelDensity * 50
-        implicitHeight: contentItem.implicitHeight + spacing + outerSpacing * 2 + buttonsRight.implicitHeight
+        implicitHeight: defaultContentItem.implicitHeight + spacing + outerSpacing * 2 + buttonsRight.implicitHeight
         implicitWidth: Math.min(Screen.desktopAvailableWidth * 0.9, Math.max(
-            contentItem.implicitWidth, buttonsRowImplicitWidth, Screen.pixelDensity * 50) + outerSpacing * 2);
+            defaultContentItem.implicitWidth, buttonsRowImplicitWidth, Screen.pixelDensity * 50) + outerSpacing * 2);
         color: palette.window
         focus: root.visible
         Keys.onPressed: {
@@ -81,7 +81,7 @@ AbstractDialog {
         SystemPalette { id: palette }
 
         Item {
-            id: contentItem
+            id: defaultContentItem
             anchors {
                 left: parent.left
                 right: parent.right
@@ -101,10 +101,10 @@ AbstractDialog {
             }
 
             Repeater {
-                model: standardButtonsLeftModel
+                id: buttonsLeftRepeater
                 Button {
-                    text: standardButtonsLeftModel[index].text
-                    onClicked: root.click(standardButtonsLeftModel[index].standardButton)
+                    text: (buttonsLeftRepeater.model && buttonsLeftRepeater.model[index] ? buttonsLeftRepeater.model[index].text : index)
+                    onClicked: root.click(buttonsLeftRepeater.model[index].standardButton)
                 }
             }
 
@@ -127,17 +127,19 @@ AbstractDialog {
             }
 
             Repeater {
-                model: standardButtonsRightModel
+                id: buttonsRightRepeater
                 // TODO maybe: insert gaps if the button requires it (destructive buttons only)
                 Button {
-                    text: standardButtonsRightModel[index].text
-                    onClicked: root.click(standardButtonsRightModel[index].standardButton)
+                    text: (buttonsRightRepeater.model && buttonsRightRepeater.model[index] ? buttonsRightRepeater.model[index].text : index)
+                    onClicked: root.click(buttonsRightRepeater.model[index].standardButton)
                 }
             }
         }
     }
-    function calculateImplicitWidth() {
-        if (standardButtonsRightModel.length < 2)
+    function setupButtons() {
+        buttonsLeftRepeater.model = root.__standardButtonsLeftModel()
+        buttonsRightRepeater.model = root.__standardButtonsRightModel()
+        if (!buttonsRightRepeater.model || buttonsRightRepeater.model.length < 2)
             return;
         var calcWidth = 0;
 
@@ -157,6 +159,6 @@ AbstractDialog {
             calculateForButton(i, buttonsLeft.visibleChildren[i])
         content.buttonsRowImplicitWidth = calcWidth + content.spacing
     }
-    onStandardButtonsChanged: calculateImplicitWidth()
-    Component.onCompleted: calculateImplicitWidth()
+    onStandardButtonsChanged: setupButtons()
+    Component.onCompleted: setupButtons()
 }
diff --git a/src/dialogs/qquickabstractdialog.cpp b/src/dialogs/qquickabstractdialog.cpp
index 62d59c19..005d1015 100644
--- a/src/dialogs/qquickabstractdialog.cpp
+++ b/src/dialogs/qquickabstractdialog.cpp
@@ -57,9 +57,8 @@ QQuickAbstractDialog::QQuickAbstractDialog(QObject *parent)
     , m_parentWindow(0)
     , m_visible(false)
     , m_modality(Qt::WindowModal)
-    , m_qmlImplementation(0)
-    , m_dialogWindow(0)
     , m_contentItem(0)
+    , m_dialogWindow(0)
     , m_windowDecoration(0)
     , m_hasNativeWindows(QGuiApplicationPrivate::platformIntegration()->
         hasCapability(QPlatformIntegration::MultipleWindows) &&
@@ -87,71 +86,64 @@ void QQuickAbstractDialog::setVisible(bool v)
             helper()->hide();
         }
     } else {
-        // For a pure QML implementation, there is no helper.
-        // But m_implementation is probably either an Item or a Window at this point.
-        if (!m_dialogWindow) {
-            m_dialogWindow = qobject_cast<QWindow *>(m_qmlImplementation);
-            if (!m_dialogWindow) {
-                m_contentItem = qobject_cast<QQuickItem *>(m_qmlImplementation);
-                if (m_contentItem) {
-                    if (m_hasNativeWindows)
-                        m_dialogWindow = m_contentItem->window();
-                    // An Item-based dialog implementation doesn't come with a window, so
-                    // we have to instantiate one iff the platform allows it.
-                    if (!m_dialogWindow && m_hasNativeWindows) {
-                        QQuickWindow *win = new QQuickWindow;
-                        ((QObject *)win)->setParent(this); // memory management only
-                        m_dialogWindow = win;
-                        m_contentItem->setParentItem(win->contentItem());
-                        QSize minSize = QSize(m_contentItem->implicitWidth(), m_contentItem->implicitHeight());
-                        QVariant minHeight = m_contentItem->property("minimumHeight");
-                        if (minHeight.isValid()) {
-                            if (minHeight.toInt() > minSize.height())
-                                minSize.setHeight(minHeight.toDouble());
-                            connect(m_contentItem, SIGNAL(minimumHeightChanged()), this, SLOT(minimumHeightChanged()));
-                        }
-                        QVariant minWidth = m_contentItem->property("minimumWidth");
-                        if (minWidth.isValid()) {
-                            if (minWidth.toInt() > minSize.width())
-                                minSize.setWidth(minWidth.toInt());
-                            connect(m_contentItem, SIGNAL(minimumWidthChanged()), this, SLOT(minimumWidthChanged()));
-                        }
-                        m_dialogWindow->setMinimumSize(minSize);
-                        connect(win, SIGNAL(widthChanged(int)), this, SLOT(windowGeometryChanged()));
-                        connect(win, SIGNAL(heightChanged(int)), this, SLOT(windowGeometryChanged()));
-                    }
+        // Pure QML implementation: wrap the contentItem in a window, or fake it
+        if (!m_dialogWindow && m_contentItem) {
+            if (m_hasNativeWindows)
+                m_dialogWindow = m_contentItem->window();
+            // An Item-based dialog implementation doesn't come with a window, so
+            // we have to instantiate one iff the platform allows it.
+            if (!m_dialogWindow && m_hasNativeWindows) {
+                QQuickWindow *win = new QQuickWindow;
+                ((QObject *)win)->setParent(this); // memory management only
+                m_dialogWindow = win;
+                m_contentItem->setParentItem(win->contentItem());
+                QSize minSize = QSize(m_contentItem->implicitWidth(), m_contentItem->implicitHeight());
+                QVariant minHeight = m_contentItem->property("minimumHeight");
+                if (minHeight.isValid()) {
+                    if (minHeight.toInt() > minSize.height())
+                        minSize.setHeight(minHeight.toDouble());
+                    connect(m_contentItem, SIGNAL(minimumHeightChanged()), this, SLOT(minimumHeightChanged()));
+                }
+                QVariant minWidth = m_contentItem->property("minimumWidth");
+                if (minWidth.isValid()) {
+                    if (minWidth.toInt() > minSize.width())
+                        minSize.setWidth(minWidth.toInt());
+                    connect(m_contentItem, SIGNAL(minimumWidthChanged()), this, SLOT(minimumWidthChanged()));
+                }
+                m_dialogWindow->setMinimumSize(minSize);
+                connect(win, SIGNAL(widthChanged(int)), this, SLOT(windowGeometryChanged()));
+                connect(win, SIGNAL(heightChanged(int)), this, SLOT(windowGeometryChanged()));
+            }
 
-                    QQuickItem *parentItem = qobject_cast<QQuickItem *>(parent());
+            QQuickItem *parentItem = qobject_cast<QQuickItem *>(parent());
 
-                    // If the platform does not support multiple windows, but the dialog is
-                    // implemented as an Item, then try to decorate it as a fake window and make it visible.
-                    if (parentItem && !m_dialogWindow && !m_windowDecoration) {
-                        if (m_decorationComponent) {
-                            if (m_decorationComponent->isLoading())
-                                connect(m_decorationComponent, SIGNAL(statusChanged(QQmlComponent::Status)),
-                                        this, SLOT(decorationLoaded()));
-                            else
-                                decorationLoaded();
-                        }
-                        // Window decoration wasn't possible, so just reparent it into the scene
-                        else {
-                            m_contentItem->setParentItem(parentItem);
-                            m_contentItem->setZ(10000);
-                        }
-                    }
+            // If the platform does not support multiple windows, but the dialog is
+            // implemented as an Item, then try to decorate it as a fake window and make it visible.
+            if (parentItem && !m_dialogWindow && !m_windowDecoration) {
+                if (m_decorationComponent) {
+                    if (m_decorationComponent->isLoading())
+                        connect(m_decorationComponent, SIGNAL(statusChanged(QQmlComponent::Status)),
+                                this, SLOT(decorationLoaded()));
+                    else
+                        decorationLoaded();
+                }
+                // Window decoration wasn't possible, so just reparent it into the scene
+                else {
+                    m_contentItem->setParentItem(parentItem);
+                    m_contentItem->setZ(10000);
                 }
             }
-            if (m_dialogWindow) {
-                // "grow up" to the size and position expected to achieve
-                if (!m_sizeAspiration.isNull()) {
-                    if (m_hasAspiredPosition)
-                        m_dialogWindow->setGeometry(m_sizeAspiration);
-                    else {
-                        if (m_sizeAspiration.width() > 0)
-                            m_dialogWindow->setWidth(m_sizeAspiration.width());
-                        if (m_sizeAspiration.height() > 0)
-                            m_dialogWindow->setHeight(m_sizeAspiration.height());
-                    }
+        }
+        if (m_dialogWindow) {
+            // "grow up" to the size and position expected to achieve
+            if (!m_sizeAspiration.isNull()) {
+                if (m_hasAspiredPosition)
+                    m_dialogWindow->setGeometry(m_sizeAspiration);
+                else {
+                    if (m_sizeAspiration.width() > 0)
+                        m_dialogWindow->setWidth(m_sizeAspiration.width());
+                    if (m_sizeAspiration.height() > 0)
+                        m_dialogWindow->setHeight(m_sizeAspiration.height());
                 }
                 connect(m_dialogWindow, SIGNAL(visibleChanged(bool)), this, SLOT(visibleChanged(bool)));
                 connect(m_dialogWindow, SIGNAL(xChanged(int)), this, SLOT(setX(int)));
@@ -172,7 +164,6 @@ void QQuickAbstractDialog::setVisible(bool v)
             m_dialogWindow->setVisible(v);
         }
     }
-
     emit visibilityChanged();
 }
 
@@ -237,10 +228,9 @@ void QQuickAbstractDialog::visibleChanged(bool v)
 
 void QQuickAbstractDialog::windowGeometryChanged()
 {
-    QQuickItem *content = qobject_cast<QQuickItem*>(m_qmlImplementation);
-    if (m_dialogWindow && content) {
-        content->setWidth(m_dialogWindow->width());
-        content->setHeight(m_dialogWindow->height());
+    if (m_dialogWindow && m_contentItem) {
+        m_contentItem->setWidth(m_dialogWindow->width());
+        m_contentItem->setHeight(m_dialogWindow->height());
     }
 }
 
@@ -264,9 +254,9 @@ QQuickWindow *QQuickAbstractDialog::parentWindow()
     return m_parentWindow;
 }
 
-void QQuickAbstractDialog::setQmlImplementation(QObject *obj)
+void QQuickAbstractDialog::setContentItem(QQuickItem *obj)
 {
-    m_qmlImplementation = obj;
+    m_contentItem = obj;
     if (m_dialogWindow) {
         disconnect(this, SLOT(visibleChanged(bool)));
         // Can't necessarily delete because m_dialogWindow might have been provided by the QML.
diff --git a/src/dialogs/qquickabstractdialog_p.h b/src/dialogs/qquickabstractdialog_p.h
index 79283c19..a905b097 100644
--- a/src/dialogs/qquickabstractdialog_p.h
+++ b/src/dialogs/qquickabstractdialog_p.h
@@ -82,7 +82,7 @@ public:
     bool isVisible() const { return m_visible; }
     Qt::WindowModality modality() const { return m_modality; }
     virtual QString title() const = 0;
-    QObject* qmlImplementation() { return m_qmlImplementation; }
+    QQuickItem* contentItem() { return m_contentItem; }
 
     int x() const;
     int y() const;
@@ -92,7 +92,7 @@ public:
     virtual void setVisible(bool v);
     virtual void setModality(Qt::WindowModality m);
     virtual void setTitle(const QString &t) = 0;
-    void setQmlImplementation(QObject* obj);
+    void setContentItem(QQuickItem* obj);
     bool isWindow() const { return m_hasNativeWindows; }
 
     enum StandardButton {
@@ -154,9 +154,8 @@ protected:
     Qt::WindowModality m_modality;
 
 protected: // variables for pure-QML implementations only
-    QObject *m_qmlImplementation;
-    QWindow *m_dialogWindow;
     QQuickItem *m_contentItem;
+    QWindow *m_dialogWindow;
     QQuickItem *m_windowDecoration;
     bool m_hasNativeWindows;
     QRect m_sizeAspiration;
diff --git a/src/dialogs/qquickcolordialog_p.h b/src/dialogs/qquickcolordialog_p.h
index c6ae69f8..20549459 100644
--- a/src/dialogs/qquickcolordialog_p.h
+++ b/src/dialogs/qquickcolordialog_p.h
@@ -60,8 +60,8 @@ QT_BEGIN_NAMESPACE
 class QQuickColorDialog : public QQuickAbstractColorDialog
 {
     Q_OBJECT
-    Q_PROPERTY(QObject* implementation READ qmlImplementation WRITE setQmlImplementation DESIGNABLE false)
-    Q_CLASSINFO("DefaultProperty", "implementation")    // AbstractColorDialog in QML can have only one child
+    Q_PROPERTY(QQuickItem* contentItem READ contentItem WRITE setContentItem DESIGNABLE false)
+    Q_CLASSINFO("DefaultProperty", "contentItem")    // AbstractColorDialog in QML can have only one child
 
 public:
     explicit QQuickColorDialog(QObject *parent = 0);
diff --git a/src/dialogs/qquickdialog.cpp b/src/dialogs/qquickdialog.cpp
index 9e726ccd..bed69e7b 100644
--- a/src/dialogs/qquickdialog.cpp
+++ b/src/dialogs/qquickdialog.cpp
@@ -104,13 +104,13 @@ QQuickDialog::~QQuickDialog()
 {
 }
 
-QJSValue QQuickDialog::standardButtonsLeftModel()
+QJSValue QQuickDialog::__standardButtonsLeftModel()
 {
     updateStandardButtons();
     return m_standardButtonsLeftModel;
 }
 
-QJSValue QQuickDialog::standardButtonsRightModel()
+QJSValue QQuickDialog::__standardButtonsRightModel()
 {
     updateStandardButtons();
     return m_standardButtonsRightModel;
diff --git a/src/dialogs/qquickdialog_p.h b/src/dialogs/qquickdialog_p.h
index 54718221..d8b95234 100644
--- a/src/dialogs/qquickdialog_p.h
+++ b/src/dialogs/qquickdialog_p.h
@@ -68,10 +68,8 @@ class QQuickDialog : public QQuickAbstractDialog
     Q_PROPERTY(QString title READ title WRITE setTitle NOTIFY titleChanged)
     Q_PROPERTY(QQuickAbstractDialog::StandardButtons standardButtons READ standardButtons WRITE setStandardButtons NOTIFY standardButtonsChanged)
     Q_PROPERTY(QQuickAbstractDialog::StandardButton clickedButton READ clickedButton NOTIFY buttonClicked)
-    Q_PROPERTY(QObject* implementation READ qmlImplementation WRITE setQmlImplementation DESIGNABLE false)
-    Q_PROPERTY(QJSValue standardButtonsLeftModel READ standardButtonsLeftModel NOTIFY standardButtonsChanged)
-    Q_PROPERTY(QJSValue standardButtonsRightModel READ standardButtonsRightModel NOTIFY standardButtonsChanged)
-    Q_CLASSINFO("DefaultProperty", "implementation")    // Dialog in QML can have only one child
+    Q_PROPERTY(QQuickItem* contentItem READ contentItem WRITE setContentItem DESIGNABLE false)
+    Q_CLASSINFO("DefaultProperty", "contentItem")    // Dialog in QML can have only one child
 
 public:
     explicit QQuickDialog(QObject *parent = 0);
@@ -79,8 +77,8 @@ public:
 
     StandardButtons standardButtons() const { return m_enabledButtons; }
     StandardButton clickedButton() const { return m_clickedButton; }
-    QJSValue standardButtonsLeftModel();
-    QJSValue standardButtonsRightModel();
+    Q_INVOKABLE QJSValue __standardButtonsLeftModel();
+    Q_INVOKABLE QJSValue __standardButtonsRightModel();
 
     QString title() const { return m_title; }
 
diff --git a/src/dialogs/qquickfiledialog_p.h b/src/dialogs/qquickfiledialog_p.h
index 0cfef472..1d2f37ab 100644
--- a/src/dialogs/qquickfiledialog_p.h
+++ b/src/dialogs/qquickfiledialog_p.h
@@ -62,9 +62,9 @@ QT_BEGIN_NAMESPACE
 class QQuickFileDialog : public QQuickAbstractFileDialog
 {
     Q_OBJECT
-    Q_PROPERTY(QObject* implementation READ qmlImplementation WRITE setQmlImplementation DESIGNABLE false)
+    Q_PROPERTY(QQuickItem* contentItem READ contentItem WRITE setContentItem DESIGNABLE false)
     Q_PROPERTY(QJSValue shortcuts READ shortcuts CONSTANT)
-    Q_CLASSINFO("DefaultProperty", "implementation")    // AbstractFileDialog in QML can have only one child
+    Q_CLASSINFO("DefaultProperty", "contentItem")    // AbstractFileDialog in QML can have only one child
 
 public:
     explicit QQuickFileDialog(QObject *parent = 0);
diff --git a/src/dialogs/qquickfontdialog_p.h b/src/dialogs/qquickfontdialog_p.h
index c51e1fd9..a6f2ee4e 100644
--- a/src/dialogs/qquickfontdialog_p.h
+++ b/src/dialogs/qquickfontdialog_p.h
@@ -60,8 +60,8 @@ QT_BEGIN_NAMESPACE
 class QQuickFontDialog : public QQuickAbstractFontDialog
 {
     Q_OBJECT
-    Q_PROPERTY(QObject* implementation READ qmlImplementation WRITE setQmlImplementation DESIGNABLE false)
-    Q_CLASSINFO("DefaultProperty", "implementation")
+    Q_PROPERTY(QQuickItem* contentItem READ contentItem WRITE setContentItem DESIGNABLE false)
+    Q_CLASSINFO("DefaultProperty", "contentItem")
 
 public:
     explicit QQuickFontDialog(QObject *parent = 0);
diff --git a/src/dialogs/qquickmessagedialog_p.h b/src/dialogs/qquickmessagedialog_p.h
index b21d8cba..80a0b04d 100644
--- a/src/dialogs/qquickmessagedialog_p.h
+++ b/src/dialogs/qquickmessagedialog_p.h
@@ -60,8 +60,8 @@ QT_BEGIN_NAMESPACE
 class QQuickMessageDialog : public QQuickAbstractMessageDialog
 {
     Q_OBJECT
-    Q_PROPERTY(QObject* implementation READ qmlImplementation WRITE setQmlImplementation DESIGNABLE false)
-    Q_CLASSINFO("DefaultProperty", "implementation")    // AbstractMessageDialog in QML can have only one child
+    Q_PROPERTY(QQuickItem* contentItem READ contentItem WRITE setContentItem DESIGNABLE false)
+    Q_CLASSINFO("DefaultProperty", "contentItem")    // AbstractMessageDialog in QML can have only one child
 
 public:
     explicit QQuickMessageDialog(QObject *parent = 0);