Fix items in layouts not being rendered when layers are used

A layer effect is apparently considered a child item of the layout
that manages the item, and this causes issues when layouting.

As was done for positioners in 865b4ec8, exclude
any items for which QQuickItemPrivate::isTransparentForPositioner()
returns true from layouting. As that commit made QQuickItemLayer set it
to true when the layer is enabled, QQuickShaderEffectSource will be
excluded from layouting.

Task-number: QTBUG-63269
Change-Id: I463ff8d0cea0dfd6c4273f376de347971040d3d0
Reviewed-by: Mitch Curtis <mitch.curtis@qt.io>
Reviewed-by: Jan Arve Sæther <jan-arve.saether@qt.io>

3 files changed, 99 insertions, 0 deletions

diff --git a/src/imports/layouts/qquicklayout.cpp b/src/imports/layouts/qquicklayout.cpp
index b3a5a2cfc8..cc206bcb95 100644
--- a/src/imports/layouts/qquicklayout.cpp
+++ b/src/imports/layouts/qquicklayout.cpp
@@ -764,6 +764,9 @@ bool QQuickLayout::shouldIgnoreItem(QQuickItem *child, QQuickLayoutAttached *&in
         ignoreItem = effectiveMaxSize.isNull();
     }
 
+    if (!ignoreItem && childPrivate->isTransparentForPositioner())
+        ignoreItem = true;
+
     if (ignoreItem)
         d->m_ignoredItems << child;
     return ignoreItem;
diff --git a/tests/auto/quick/qquicklayouts/data/rowlayout/LayerEnabled.qml b/tests/auto/quick/qquicklayouts/data/rowlayout/LayerEnabled.qml
new file mode 100644
index 0000000000..39500cc19d
--- /dev/null
+++ b/tests/auto/quick/qquicklayouts/data/rowlayout/LayerEnabled.qml
@@ -0,0 +1,78 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the test suite of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** BSD License Usage
+** Alternatively, you may use this file under the terms of the BSD license
+** as follows:
+**
+** "Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+**   * Redistributions of source code must retain the above copyright
+**     notice, this list of conditions and the following disclaimer.
+**   * Redistributions in binary form must reproduce the above copyright
+**     notice, this list of conditions and the following disclaimer in
+**     the documentation and/or other materials provided with the
+**     distribution.
+**   * Neither the name of The Qt Company Ltd nor the names of its
+**     contributors may be used to endorse or promote products derived
+**     from this software without specific prior written permission.
+**
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+import QtQuick 2.7
+import QtQuick.Layouts 1.3
+
+Rectangle {
+    width: 100
+    height: 100
+    color: "black"
+
+    property alias layout: layout
+    property alias item1: r1
+
+    RowLayout {
+        id: layout
+        anchors.fill: parent
+        visible: false
+        spacing: 0
+
+        Rectangle {
+            id: r1
+            color: "red"
+
+            layer.enabled: true
+
+            Layout.fillWidth: true
+            Layout.fillHeight: true
+        }
+    }
+}
diff --git a/tests/auto/quick/qquicklayouts/data/tst_rowlayout.qml b/tests/auto/quick/qquicklayouts/data/tst_rowlayout.qml
index 763c4cf6e4..07af6a77ac 100644
--- a/tests/auto/quick/qquicklayouts/data/tst_rowlayout.qml
+++ b/tests/auto/quick/qquicklayouts/data/tst_rowlayout.qml
@@ -1082,5 +1082,23 @@ Item {
 
             // Shouldn't crash upon destroying containerUser.
         }
+
+        /*
+            Tests that a layout-managed item that sets layer.enabled to true
+            still renders something. This is a simpler test case that only
+            reproduces the issue when the layout that manages it is made visible
+            after component completion, but QTBUG-63269 has a more complex example
+            where this (setting visible to true afterwards) isn't necessary.
+        */
+        function test_layerEnabled() {
+            var component = Qt.createComponent("rowlayout/LayerEnabled.qml");
+            compare(component.status, Component.Ready);
+
+            var rootRect = createTemporaryObject(component, container);
+            verify(rootRect);
+            rootRect.layout.visible = true;
+            waitForRendering(rootRect.layout)
+            compare(rootRect.item1.width, 100)
+        }
     }
 }