Fix broken value-type support by allowing property definition

In QtQuick 1.x the "variant" property type was supported, which could
be used to allow value type properties to be defined in QML.  In
QtQuick 2.0, we have deprecated the "variant" property, but its
replacement ("var") is not suited for defining lightweight C++ type
values (such as QColor, QFont, QRectF, QVector3D etc).

This commit allows those QML basic types to be used in QML once more,
by supporting them in the property definition syntax.

Note that since some value types are provided by QtQuick and others
are provided by QtQml, if a client imports only QtQml they can define
but not use properties of certain types (eg, font).

Task-number: QTBUG-21034
Task-number: QTBUG-18217

Change-Id: Ia951a8522f223408d27293bb96c276281a710277
Reviewed-by: Matthew Vogt <matthew.vogt@nokia.com>

1 files changed, 25 insertions, 12 deletions

diff --git a/src/qml/qml/qqmlglobal.cpp b/src/qml/qml/qqmlglobal.cpp
index 6f4942963f..0ebc802dec 100644
--- a/src/qml/qml/qqmlglobal.cpp
+++ b/src/qml/qml/qqmlglobal.cpp
@@ -175,42 +175,58 @@ QVariant QQmlValueTypeProvider::createVariantFromString(int type, const QString
     return QVariant();
 }
 
-bool QQmlValueTypeProvider::equalValueType(int type, const void *lhs, const void *rhs)
+QVariant QQmlValueTypeProvider::createVariantFromJsObject(int type, QQmlV8Handle obj, QV8Engine *e, bool *ok)
+{
+    QVariant v;
+
+    QQmlValueTypeProvider *p = this;
+    do {
+        if (p->variantFromJsObject(type, obj, e, &v)) {
+            if (ok) *ok = true;
+            return v;
+        }
+    } while ((p = p->next));
+
+    if (ok) *ok = false;
+    return QVariant();
+}
+
+bool QQmlValueTypeProvider::equalValueType(int type, const void *lhs, const void *rhs, size_t rhsSize)
 {
     Q_ASSERT(lhs);
     Q_ASSERT(rhs);
 
     QQmlValueTypeProvider *p = this;
     do {
-        if (p->equal(type, lhs, rhs))
+        if (p->equal(type, lhs, rhs, rhsSize))
             return true;
     } while ((p = p->next));
 
     return false;
 }
 
-bool QQmlValueTypeProvider::storeValueType(int type, const void *src, void *dst, size_t n)
+bool QQmlValueTypeProvider::storeValueType(int type, const void *src, void *dst, size_t dstSize)
 {
     Q_ASSERT(src);
     Q_ASSERT(dst);
 
     QQmlValueTypeProvider *p = this;
     do {
-        if (p->store(type, src, dst, n))
+        if (p->store(type, src, dst, dstSize))
             return true;
     } while ((p = p->next));
 
     return false;
 }
 
-bool QQmlValueTypeProvider::readValueType(int srcType, const void *src, int dstType, void *dst)
+bool QQmlValueTypeProvider::readValueType(int srcType, const void *src, size_t srcSize, int dstType, void *dst)
 {
     Q_ASSERT(src);
     Q_ASSERT(dst);
 
     QQmlValueTypeProvider *p = this;
     do {
-        if (p->read(srcType, src, dstType, dst))
+        if (p->read(srcType, src, srcSize, dstType, dst))
             return true;
     } while ((p = p->next));
 
@@ -240,9 +256,10 @@ bool QQmlValueTypeProvider::createFromString(int, const QString &, void *, size_
 bool QQmlValueTypeProvider::createStringFrom(int, const void *, QString *) { return false; }
 bool QQmlValueTypeProvider::variantFromString(const QString &, QVariant *) { return false; }
 bool QQmlValueTypeProvider::variantFromString(int, const QString &, QVariant *) { return false; }
-bool QQmlValueTypeProvider::equal(int, const void *, const void *) { return false; }
+bool QQmlValueTypeProvider::variantFromJsObject(int, QQmlV8Handle, QV8Engine *, QVariant *) { return false; }
+bool QQmlValueTypeProvider::equal(int, const void *, const void *, size_t) { return false; }
 bool QQmlValueTypeProvider::store(int, const void *, void *, size_t) { return false; }
-bool QQmlValueTypeProvider::read(int, const void *, int, void *) { return false; }
+bool QQmlValueTypeProvider::read(int, const void *, size_t, int, void *) { return false; }
 bool QQmlValueTypeProvider::write(int, const void *, void *, size_t) { return false; }
 
 static QQmlValueTypeProvider *valueTypeProvider = 0;
@@ -266,10 +283,6 @@ Q_QML_PRIVATE_EXPORT void QQml_addValueTypeProvider(QQmlValueTypeProvider *newPr
 
 Q_AUTOTEST_EXPORT QQmlValueTypeProvider *QQml_valueTypeProvider(void)
 {
-    if (valueTypeProvider == 0) {
-        qWarning() << "Warning: QQml_valueTypeProvider: no value type provider has been set!";
-    }
-
     static QQmlValueTypeProvider **providerPtr = getValueTypeProvider();
     return *providerPtr;
 }