Ensure loaded item's parent is set before component completion.

Also documented Loader sizing behavior.

Task-number: QTBUG-14873
Reviewed-by: Michael Brasser

3 files changed, 159 insertions, 6 deletions

diff --git a/doc/src/snippets/declarative/loader/sizeitem.qml b/doc/src/snippets/declarative/loader/sizeitem.qml
new file mode 100644
index 0000000..6ace8d6
--- /dev/null
+++ b/doc/src/snippets/declarative/loader/sizeitem.qml
@@ -0,0 +1,62 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the documentation of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+//![0]
+import QtQuick 1.0
+
+Item {
+    width: 200; height: 200
+
+    Loader {
+        // position the Loader in the center of the parent
+        anchors.centerIn: parent
+        sourceComponent: rect
+    }
+
+    Component {
+        id: rect
+        Rectangle {
+            width: 50
+            height: 50
+            color: "red"
+        }
+    }
+}
+//![0]
diff --git a/doc/src/snippets/declarative/loader/sizeloader.qml b/doc/src/snippets/declarative/loader/sizeloader.qml
new file mode 100644
index 0000000..eac7d57
--- /dev/null
+++ b/doc/src/snippets/declarative/loader/sizeloader.qml
@@ -0,0 +1,62 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the documentation of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+//![0]
+import QtQuick 1.0
+
+Item {
+    width: 200; height: 200
+
+    Loader {
+        // Explicitly set the size of the Loader to the parent item's size
+        anchors.fill: parent
+        sourceComponent: rect
+    }
+
+    Component {
+        id: rect
+        Rectangle {
+            width: 50
+            height: 50
+            color: "red"
+        }
+    }
+}
+//![0]
diff --git a/src/declarative/graphicsitems/qdeclarativeloader.cpp b/src/declarative/graphicsitems/qdeclarativeloader.cpp
index 109fbbb..1119b92 100644
--- a/src/declarative/graphicsitems/qdeclarativeloader.cpp
+++ b/src/declarative/graphicsitems/qdeclarativeloader.cpp
@@ -129,15 +129,41 @@ void QDeclarativeLoaderPrivate::initResize()
 
     The loaded item can be accessed using the \l item property.
 
-    Loader is like any other visual item and must be positioned and sized 
-    accordingly to become visible. Once the component is loaded, the Loader 
-    is automatically resized to the size of the component.
-
     If the \l source or \l sourceComponent changes, any previously instantiated
     items are destroyed. Setting \l source to an empty string or setting
     \l sourceComponent to \c undefined destroys the currently loaded item,
     freeing resources and leaving the Loader empty.
 
+    \section2 Loader sizing behavior
+
+    Loader is like any other visual item and must be positioned and sized
+    accordingly to become visible.
+
+    \list
+    \o If an explicit size is not specified for the Loader, the Loader
+    is automatically resized to the size of the loaded item once the
+    component is loaded.
+    \o If the size of the Loader is specified explicitly by setting
+    the width, height or by anchoring, the loaded item will be resized
+    to the size of the Loader.
+    \endlist
+
+    In both scenarios the size of the item and the Loader are identical.
+    This ensures that anchoring to the Loader is equivalent to anchoring
+    to the loaded item.
+
+    \table
+    \row
+    \o sizeloader.qml
+    \o sizeitem.qml
+    \row
+    \o \snippet doc/src/snippets/declarative/loader/sizeloader.qml 0
+    \o \snippet doc/src/snippets/declarative/loader/sizeitem.qml 0
+    \row
+    \o The red rectangle will be sized to the size of the root item.
+    \o The red rectangle will be 50x50, centered in the root item.
+    \endtable
+
 
     \section2 Receiving signals from loaded items
 
@@ -343,12 +369,14 @@ void QDeclarativeLoaderPrivate::_q_sourceLoaded()
         QDeclarativeContext *ctxt = new QDeclarativeContext(creationContext);
         ctxt->setContextObject(q);
 
-        QDeclarativeComponent *c = component;
-        QObject *obj = component->create(ctxt);
+        QDeclarativeGuard<QDeclarativeComponent> c = component;
+        QObject *obj = component->beginCreate(ctxt);
         if (component != c) {
             // component->create could trigger a change in source that causes
             // component to be set to something else. In that case we just
             // need to cleanup.
+            if (c)
+                c->completeCreate();
             delete obj;
             delete ctxt;
             return;
@@ -373,6 +401,7 @@ void QDeclarativeLoaderPrivate::_q_sourceLoaded()
             delete ctxt;
             source = QUrl();
         }
+        component->completeCreate();
         emit q->sourceChanged();
         emit q->statusChanged();
         emit q->progressChanged();