Add WheelHandler

It can be used to change any qreal property of its target Item in
response to wheel rotation, or it can be used in other ways that involve
bindings but without a target item.

[ChangeLog][QtQuick][Event Handlers] Added WheelHandler, which handles
mouse wheel rotation by modifying arbitrary Item properties.

Fixes: QTBUG-68119
Change-Id: I247e2325ee993cc1b91a47fbd6c4ba0ffde7ad49
Reviewed-by: Jan Arve Sæther <jan-arve.saether@qt.io>

1 files changed, 43 insertions, 0 deletions

diff --git a/tests/auto/quick/pointerhandlers/qquickwheelhandler/data/rectWheel.qml b/tests/auto/quick/pointerhandlers/qquickwheelhandler/data/rectWheel.qml
new file mode 100644
index 0000000000..b2272a57c2
--- /dev/null
+++ b/tests/auto/quick/pointerhandlers/qquickwheelhandler/data/rectWheel.qml
@@ -0,0 +1,43 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the test suite of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:GPL-EXCEPT$
+** 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.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 as published by the Free Software
+** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+import QtQuick 2.14
+
+Rectangle {
+    width: 320; height: 240
+    color: "green"; antialiasing: true
+
+    Rectangle {
+        width: 100; height: 2; anchors.centerIn: parent
+        Rectangle {
+            width: 2; height: 100; anchors.centerIn: parent
+        }
+    }
+
+    WheelHandler { }
+}