Control widget property connection improvements

src/skin/legacyskinparser.h

@@ -104,7 +104,6 @@ class LegacySkinParser : public QObject, public SkinParser {
     QWidget* parseSizeAwareStack(const QDomElement& node);
     QWidget* parseSplitter(const QDomElement& node);
     void parseSingletonDefinition(const QDomElement& node);
-    QWidget* parseSingletonContainer(const QDomElement& node);
 
     // Visual widgets.
     QWidget* parseVisual(const QDomElement& node);

src/widget/controlwidgetconnection.cpp

@@ -9,6 +9,28 @@
 #include "util/valuetransformer.h"
 #include "widget/wbasewidget.h"
 
+namespace {
+
+QMetaProperty propertyFromWidget(const QWidget* pWidget, const QString& name) {
+    VERIFY_OR_DEBUG_ASSERT(!name.isEmpty()) {
+        return QMetaProperty();
+    }
+    VERIFY_OR_DEBUG_ASSERT(pWidget) {
+        return QMetaProperty();
+    }
+    const QMetaObject* meta = pWidget->metaObject();
+    VERIFY_OR_DEBUG_ASSERT(meta) {
+        return QMetaProperty();
+    }
+    const int id = meta->indexOfProperty(name.toLatin1().constData());
+    VERIFY_OR_DEBUG_ASSERT(id >= 0) {
+        return QMetaProperty();
+    }
+    return meta->property(id);
+}
+
+} // namespace
+
 ControlWidgetConnection::ControlWidgetConnection(
         WBaseWidget* pBaseWidget,
         const ConfigKey& key,
@@ -67,7 +89,7 @@ QString ControlParameterWidgetConnection::toDebugString() const {
 
 void ControlParameterWidgetConnection::slotControlValueChanged(double value) {
     if (m_directionOption & DIR_TO_WIDGET) {
-        double parameter = getControlParameterForValue(value);
+        const double parameter = getControlParameterForValue(value);
         m_pWidget->onConnectedControlChanged(parameter, value);
     }
 }
@@ -97,40 +119,58 @@ void ControlParameterWidgetConnection::setControlParameterUp(double v) {
 }
 
 ControlWidgetPropertyConnection::ControlWidgetPropertyConnection(
-        WBaseWidget* pBaseWidget, const ConfigKey& key,
-        ValueTransformer* pTransformer, const QString& propertyName)
+        WBaseWidget* pBaseWidget,
+        const ConfigKey& key,
+        ValueTransformer* pTransformer,
+        const QString& propertyName)
         : ControlWidgetConnection(pBaseWidget, key, pTransformer),
-          m_propertyName(propertyName.toLatin1()) {
+          m_propertyName(propertyName),
+          m_property(propertyFromWidget(pBaseWidget->toQWidget(), propertyName)) {
+    // Initial update to synchronize the property in all the sub widgets
     slotControlValueChanged(m_pControl->get());
 }
 
 QString ControlWidgetPropertyConnection::toDebugString() const {
     const ConfigKey& key = getKey();
-    return QString("%1,%2 Parameter: %3 Property: %4 Value: %5").arg(
-            key.group,
-            key.item,
-            QString::number(m_pControl->getParameter()),
-            m_propertyName,
-            m_pWidget->toQWidget()->property(m_propertyName.constData()).toString());
+    return QString("%1,%2 Parameter: %3 Property: %4 Value: %5")
+            .arg(key.group,
+                    key.item,
+                    QString::number(m_pControl->getParameter()),
+                    m_propertyName,
+                    m_property.read(m_pWidget->toQWidget()).toString());
 }
 
 void ControlWidgetPropertyConnection::slotControlValueChanged(double v) {
-    QVariant parameter;
-    QWidget* pWidget = m_pWidget->toQWidget();
-    QVariant property = pWidget->property(m_propertyName.constData());
-    if (property.type() == QVariant::Bool) {
-        parameter = getControlParameterForValue(v) > 0;
+    const double parameter = getControlParameterForValue(v);
+    QVariant vParameter;
+    if (m_property.type() == QVariant::Bool) {
+        vParameter = (parameter > 0);
     } else {
-        parameter = getControlParameterForValue(v);
+        vParameter = parameter;
+    }
+    bool success = vParameter.convert(m_property.type());
+    VERIFY_OR_DEBUG_ASSERT(success) {
+        return;
+    }
+    if (m_propertyValue == vParameter) {
+        // don't repeat writing the same value that may stall the GUI
+        // Comparing the property value directly does not work, because
+        // in some cases (e.g. visible) it has to be propagated to the child widgets.
+        return;
     }
 
-    if (!pWidget->setProperty(m_propertyName.constData(),parameter)) {
+    QWidget* pWidget = m_pWidget->toQWidget();
+    if (!m_property.write(pWidget, vParameter)) {
+        const ConfigKey& key = getKey();
         qWarning() << "Property" << m_propertyName
-                   << "was not defined for widget" << pWidget->objectName()
-                   << "of type" << pWidget->metaObject()->className()
-                   << "(parameter:" << parameter << ")";
+                   << "was not defined for widget" << pWidget
+                   << "(parameter:" << parameter << ")"
+                   << key.group << key.item;
+        return;
     }
 
+    m_propertyValue = vParameter;
+
     // According to http://stackoverflow.com/a/3822243 this is the least
     // expensive way to restyle just this widget.
     pWidget->style()->unpolish(pWidget);

src/widget/controlwidgetconnection.h

@@ -1,9 +1,10 @@
 #pragma once
 
+#include <QByteArray>
+#include <QMetaProperty>
 #include <QObject>
-#include <QString>
 #include <QScopedPointer>
-#include <QByteArray>
+#include <QString>
 
 #include "control/controlproxy.h"
 #include "util/valuetransformer.h"
@@ -137,5 +138,7 @@ class ControlWidgetPropertyConnection final : public ControlWidgetConnection {
     void slotControlValueChanged(double v) override;
 
   private:
-    QByteArray m_propertyName;
+    const QString m_propertyName;
+    const QMetaProperty m_property;
+    QVariant m_propertyValue;
 };