Enabled the use of promoted widgets in new form templates.

The form builder used for preview of the templates did not implement
custom widget handling (FormBuilder::createCustomWidgets()).
On encountering a promoted widget, the widget factory
would then create a Widget Database entry specifying QWidget
inheritance (emergency fallback) which could not be overidden later
on.
To fix this, moved the code for handling custom widgets from
QDesignerResource to QSimpleResource and create a new
formbuilder class that handles it especially for the New Form Dialog
preview.

Task-number:  254282

1 files changed, 133 insertions, 0 deletions

diff --git a/tools/designer/src/lib/shared/qsimpleresource.cpp b/tools/designer/src/lib/shared/qsimpleresource.cpp
index 8d29002..69d48fd 100644
--- a/tools/designer/src/lib/shared/qsimpleresource.cpp
+++ b/tools/designer/src/lib/shared/qsimpleresource.cpp
@@ -41,6 +41,7 @@
 
 #include "qsimpleresource_p.h"
 #include "widgetfactory_p.h"
+#include "widgetdatabase_p.h"
 
 #include <formscriptrunner_p.h>
 #include <properties_p.h>
@@ -57,6 +58,8 @@
 #include <QtGui/QWidget>
 #include <QtGui/QAction>
 #include <QtCore/QDebug>
+#include <QtCore/QCoreApplication>
+
 
 QT_BEGIN_NAMESPACE
 
@@ -267,6 +270,136 @@ bool QSimpleResource::warningsEnabled()
     return m_warningsEnabled;
 }
 
+// Custom widgets handling helpers
+
+// Add unique fake slots and signals to lists
+bool QSimpleResource::addFakeMethods(const DomSlots *domSlots, QStringList &fakeSlots, QStringList &fakeSignals)
+{
+    if (!domSlots)
+        return false;
+
+    bool rc = false;
+    foreach (const QString &fakeSlot, domSlots->elementSlot())
+        if (fakeSlots.indexOf(fakeSlot) == -1) {
+            fakeSlots += fakeSlot;
+            rc = true;
+        }
+
+    foreach (const QString &fakeSignal, domSlots->elementSignal())
+        if (fakeSignals.indexOf(fakeSignal) == -1) {
+            fakeSignals += fakeSignal;
+            rc = true;
+        }
+    return rc;
+}
+
+void QSimpleResource::addFakeMethodsToWidgetDataBase(const DomCustomWidget *domCustomWidget, WidgetDataBaseItem *item)
+{
+    const DomSlots *domSlots = domCustomWidget->elementSlots();
+    if (!domSlots)
+        return;
+
+    // Merge in new slots, signals
+    QStringList fakeSlots = item->fakeSlots();
+    QStringList fakeSignals = item->fakeSignals();
+    if (addFakeMethods(domSlots, fakeSlots, fakeSignals)) {
+        item->setFakeSlots(fakeSlots);
+        item->setFakeSignals(fakeSignals);
+    }
+}
+
+// Perform one iteration of adding the custom widgets to the database,
+// looking up the base class and inheriting its data.
+// Remove the succeeded custom widgets from the list.
+// Classes whose base class could not be found are left in the list.
+
+void QSimpleResource::addCustomWidgetsToWidgetDatabase(const QDesignerFormEditorInterface *core,
+                                                       QList<DomCustomWidget*>& custom_widget_list)
+{
+    QDesignerWidgetDataBaseInterface *db = core->widgetDataBase();
+    for (int i=0; i < custom_widget_list.size(); ) {
+        bool classInserted = false;
+        DomCustomWidget *custom_widget = custom_widget_list[i];
+        const QString customClassName = custom_widget->elementClass();
+        const QString base_class = custom_widget->elementExtends();
+        QString includeFile;
+        IncludeType includeType = IncludeLocal;
+        if (const DomHeader *header = custom_widget->elementHeader()) {
+            includeFile = header->text();
+            if (header->hasAttributeLocation() && header->attributeLocation() == QLatin1String("global"))
+                includeType = IncludeGlobal;
+        }
+        const bool domIsContainer = custom_widget->elementContainer();
+        // Append a new item
+        if (base_class.isEmpty()) {
+            WidgetDataBaseItem *item = new WidgetDataBaseItem(customClassName);
+            item->setPromoted(false);
+            item->setGroup(QCoreApplication::translate("Designer", "Custom Widgets"));
+            item->setIncludeFile(buildIncludeFile(includeFile, includeType));
+            item->setContainer(domIsContainer);
+            item->setCustom(true);
+            addFakeMethodsToWidgetDataBase(custom_widget, item);
+            db->append(item);
+            custom_widget_list.removeAt(i);
+            classInserted = true;
+        } else {
+            // Create a new entry cloned from base class. Note that this will ignore existing
+            // classes, eg, plugin custom widgets.
+            QDesignerWidgetDataBaseItemInterface *item =
+                appendDerived(db, customClassName, QCoreApplication::translate("Designer", "Promoted Widgets"),
+                              base_class,
+                              buildIncludeFile(includeFile, includeType),
+                              true,true);
+            // Ok, base class found.
+            if (item) {
+                // Hack to accommodate for old UI-files in which "container" is not set properly:
+                // Apply "container" from DOM only if true (else, eg classes from QFrame might not accept
+                // dropping child widgets on them as container=false). This also allows for
+                // QWidget-derived stacked pages.
+                if (domIsContainer)
+                    item->setContainer(domIsContainer);
+
+                addFakeMethodsToWidgetDataBase(custom_widget, static_cast<WidgetDataBaseItem*>(item));
+                custom_widget_list.removeAt(i);
+                classInserted = true;
+            }
+        }
+        // Skip failed item.
+        if (!classInserted)
+            i++;
+    }
+
+}
+
+void QSimpleResource::handleDomCustomWidgets(const QDesignerFormEditorInterface *core,
+                                             const DomCustomWidgets *dom_custom_widgets)
+{
+    if (dom_custom_widgets == 0)
+        return;
+    QList<DomCustomWidget*> custom_widget_list = dom_custom_widgets->elementCustomWidget();
+    // Attempt to insert each item derived from its base class.
+    // This should at most require two iterations in the event that the classes are out of order
+    // (derived first, max depth: promoted custom plugin = 2)
+    for (int iteration = 0;  iteration < 2;  iteration++) {
+        addCustomWidgetsToWidgetDatabase(core, custom_widget_list);
+        if (custom_widget_list.empty())
+            return;
+    }
+    // Oops, there are classes left whose base class could not be found.
+    // Default them to QWidget with warnings.
+    const QString fallBackBaseClass = QLatin1String("QWidget");
+    for (int i=0; i < custom_widget_list.size(); i++ ) {
+        DomCustomWidget *custom_widget = custom_widget_list[i];
+        const QString customClassName = custom_widget->elementClass();
+        const QString base_class = custom_widget->elementExtends();
+        qDebug() << "** WARNING The base class " << base_class << " of the custom widget class " << customClassName
+            << " could not be found. Defaulting to " << fallBackBaseClass << '.';
+        custom_widget->setElementExtends(fallBackBaseClass);
+    }
+    // One more pass.
+    addCustomWidgetsToWidgetDatabase(core, custom_widget_list);
+}
+
 // ------------ FormBuilderClipboard
 
 FormBuilderClipboard::FormBuilderClipboard(QWidget *w)