Revamp invoke example

Pick-to: 6.5
Task-number: QTBUG-111323
Change-Id: If4549b346a824873753f512a4e3c7d4ccc2b1f88
Reviewed-by: Ulf Hermann <ulf.hermann@qt.io>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>

12 files changed, 101 insertions, 70 deletions

diff --git a/examples/scxml/invoke/Button.qml b/examples/scxml/invoke/Button.qml
index 0b7e6b2..5be5665 100644
--- a/examples/scxml/invoke/Button.qml
+++ b/examples/scxml/invoke/Button.qml
@@ -1,6 +1,8 @@
-// Copyright (C) 2016 The Qt Company Ltd.
+// Copyright (C) 2023 The Qt Company Ltd.
 // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
 
+pragma ComponentBehavior: Bound
+
 import QtQuick
 
 Item {
diff --git a/examples/scxml/invoke/CMakeLists.txt b/examples/scxml/invoke/CMakeLists.txt
index 93bbf58..5511792 100644
--- a/examples/scxml/invoke/CMakeLists.txt
+++ b/examples/scxml/invoke/CMakeLists.txt
@@ -1,11 +1,9 @@
-# Copyright (C) 2022 The Qt Company Ltd.
+# Copyright (C) 2023 The Qt Company Ltd.
 # SPDX-License-Identifier: BSD-3-Clause
 
 cmake_minimum_required(VERSION 3.16)
 project(invoke LANGUAGES CXX)
 
-set(CMAKE_AUTOMOC ON)
-
 if(NOT DEFINED INSTALL_EXAMPLESDIR)
     set(INSTALL_EXAMPLESDIR "examples")
 endif()
@@ -14,6 +12,8 @@ set(INSTALL_EXAMPLEDIR "${INSTALL_EXAMPLESDIR}/scxml/invoke")
 
 find_package(Qt6 REQUIRED COMPONENTS Core Gui Qml Scxml)
 
+qt_standard_project_setup(REQUIRES 6.5)
+
 qt_add_executable(invoke
     invoke.cpp
 )
@@ -23,32 +23,29 @@ set_target_properties(invoke PROPERTIES
     MACOSX_BUNDLE TRUE
 )
 
-target_link_libraries(invoke PUBLIC
+target_link_libraries(invoke PRIVATE
     Qt6::Core
     Qt6::Gui
     Qt6::Qml
     Qt6::Scxml
 )
 
-set(invoke_resource_files
-    "Button.qml"
-    "MainView.qml"
-    "SubView.qml"
-    "invoke.qml"
-)
-
-qt6_add_resources(invoke "invoke"
-    PREFIX
-        "/"
-    FILES
-        ${invoke_resource_files}
-)
-
 # Statecharts:
 qt6_add_statecharts(invoke
     statemachine.scxml
 )
 
+qt_add_qml_module(invoke
+    URI InvokeExample
+    VERSION 1.0
+    QML_FILES
+        Button.qml
+        MainView.qml
+        SubView.qml
+    SOURCES
+        invoke-qml.h
+)
+
 install(TARGETS invoke
     RUNTIME DESTINATION "${INSTALL_EXAMPLEDIR}"
     BUNDLE DESTINATION "${INSTALL_EXAMPLEDIR}"
diff --git a/examples/scxml/invoke/MainView.qml b/examples/scxml/invoke/MainView.qml
index 6ae5155..c7a4400 100644
--- a/examples/scxml/invoke/MainView.qml
+++ b/examples/scxml/invoke/MainView.qml
@@ -1,19 +1,25 @@
-// Copyright (C) 2016 The Qt Company Ltd.
+// Copyright (C) 2023 The Qt Company Ltd.
 // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
 
+pragma ComponentBehavior: Bound
+
 import QtQuick
 import QtQuick.Window
 import QtScxml
+import InvokeExample
 
 Window {
     id: window
     visible: true
-    property StateMachine stateMachine
-
     color: "black"
     width: 400
     height: 300
 
+    DirectionsStateMachine {
+        id: stateMachine
+        running: true
+    }
+
     Item {
         width: parent.width / 2
         height: parent.height
@@ -39,7 +45,9 @@ Window {
     }
 
     Loader {
-        source: "SubView.qml"
+        sourceComponent: SubView {
+            anywhere: services.children.anywhere ? services.children.anywhere.stateMachine : null
+        }
         active: stateMachine.somewhere
 
         x: parent.width / 2
@@ -48,11 +56,8 @@ Window {
 
         InvokedServices {
             id: services
-            stateMachine: window.stateMachine
+            stateMachine: stateMachine
         }
-
-        property var anywhere: services.children.anywhere ? services.children.anywhere.stateMachine
-                                                          : undefined
     }
 }
 
diff --git a/examples/scxml/invoke/SubView.qml b/examples/scxml/invoke/SubView.qml
index 413227b..31dbf06 100644
--- a/examples/scxml/invoke/SubView.qml
+++ b/examples/scxml/invoke/SubView.qml
@@ -1,26 +1,31 @@
-// Copyright (C) 2016 The Qt Company Ltd.
+// Copyright (C) 2023 The Qt Company Ltd.
 // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
 
+pragma ComponentBehavior: Bound
+
 import QtQuick
+import QtScxml
 
 Item {
-    // "anywhere" is a context property, so we always have to check if it's null
+    id: root
+    required property StateMachine anywhere
+
     Button {
         id: here
-        enabled: anywhere ? anywhere.here : false
+        enabled: root.anywhere ? root.anywhere.here : false
         text: "Go There"
         width: parent.width / 2
         height: parent.height
-        onClicked: anywhere.submitEvent("goThere")
+        onClicked: root.anywhere.submitEvent("goThere")
     }
 
     Button {
         id: there
-        enabled: anywhere ? anywhere.there : false
+        enabled: root.anywhere ? root.anywhere.there : false
         text: "Go Here"
         width: parent.width / 2
         height: parent.height
         x: width
-        onClicked: anywhere.submitEvent("goHere")
+        onClicked: root.anywhere.submitEvent("goHere")
     }
 }
diff --git a/examples/scxml/invoke/doc/src/invoke.qdoc b/examples/scxml/invoke/doc/src/invoke.qdoc
index b771c3d..10b5aa2 100644
--- a/examples/scxml/invoke/doc/src/invoke.qdoc
+++ b/examples/scxml/invoke/doc/src/invoke.qdoc
@@ -1,4 +1,4 @@
-// Copyright (C) 2016 The Qt Company Ltd.
+// Copyright (C) 2023 The Qt Company Ltd.
 // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
 
 /*!
@@ -20,7 +20,7 @@
     \section1 Invoking the State Machine
 
     In \e statemachine.scxml, we specify a state machine with the name
-    \e Directions of type \e http://www.w3.org/TR/scxml/ to invoke:
+    \e DirectionsStateMachine of type \e http://www.w3.org/TR/scxml/ to invoke:
 
     \quotefromfile invoke/statemachine.scxml
     \skipto scxml
@@ -56,12 +56,19 @@
     \e statemachine.cpp, which are then added appropriately as headers and sources for
     compilation.
 
+    \section1 Declaring the state machine as QML element
+
+    The state machine is declared as a QML element as follows:
+    \quotefromfile invoke/invoke-qml.h
+    \skipto struct
+    \printuntil }
+
     \section1 Instantiating the State Machine
 
-    We instantiate the generated \c Directions class in the \e invoke.cpp
+    We instantiate the generated \c DirectionsStateMachine element in the \e MainView.qml
     file, as follows:
 
-    \quotefromfile invoke/invoke.cpp
-    \skipto statemachine.h
+    \quotefromfile invoke/MainView.qml
+    \skipto DirectionsStateMachine
     \printuntil }
 */
diff --git a/examples/scxml/invoke/invoke-qml.h b/examples/scxml/invoke/invoke-qml.h
new file mode 100644
index 0000000..e0735a8
--- /dev/null
+++ b/examples/scxml/invoke/invoke-qml.h
@@ -0,0 +1,20 @@
+// Copyright (C) 2023 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
+
+#ifndef INVOKE_QML
+#define INVOKE_QML
+
+#include "statemachine.h"
+
+#include <QtQml/qqml.h>
+#include <QtCore/qobject.h>
+
+struct DirectionsStateMachineRegistration
+{
+    Q_GADGET
+    QML_FOREIGN(DirectionsStateMachine)
+    QML_NAMED_ELEMENT(DirectionsStateMachine)
+    QML_ADDED_IN_VERSION(1, 0)
+};
+
+#endif // INVOKE_QML
diff --git a/examples/scxml/invoke/invoke.cpp b/examples/scxml/invoke/invoke.cpp
index 9a64243..6680396 100644
--- a/examples/scxml/invoke/invoke.cpp
+++ b/examples/scxml/invoke/invoke.cpp
@@ -1,22 +1,17 @@
-// Copyright (C) 2016 The Qt Company Ltd.
+// Copyright (C) 2023 The Qt Company Ltd.
 // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
 
-#include <QGuiApplication>
-#include <QQmlApplicationEngine>
-#include <QQmlContext>
-
-#include "statemachine.h"
+#include <QtGui/qguiapplication.h>
+#include <QtQml/qqmlapplicationengine.h>
 
 int main(int argc, char *argv[])
 {
     QGuiApplication app(argc, argv);
 
-    qmlRegisterType<Directions>("Directions", 1, 0, "Directions");
-
     QQmlApplicationEngine engine;
-    engine.load(QUrl(QStringLiteral("qrc:/invoke.qml")));
-    if (engine.rootObjects().isEmpty())
-        return -1;
+    QObject::connect(&engine, &QQmlApplicationEngine::objectCreationFailed, &app,
+                     [](){ QCoreApplication::exit(EXIT_FAILURE); }, Qt::QueuedConnection);
+    engine.loadFromModule("InvokeExample", "MainView");
 
     return app.exec();
 }
diff --git a/examples/scxml/invoke/invoke.pro b/examples/scxml/invoke/invoke.pro
index 866ecdb..d23a0af 100644
--- a/examples/scxml/invoke/invoke.pro
+++ b/examples/scxml/invoke/invoke.pro
@@ -2,10 +2,23 @@ TEMPLATE = app
 
 QT += qml scxml
 CONFIG += c++11
+CONFIG += qmltypes
 
 SOURCES += invoke.cpp
+HEADERS += invoke-qml.h
 
-RESOURCES += invoke.qrc
+QML_IMPORT_NAME = InvokeExample
+QML_IMPORT_MAJOR_VERSION = 1
+
+qml_resources.files = \
+    qmldir \
+    Button.qml \
+    MainView.qml \
+    SubView.qml
+
+qml_resources.prefix = /qt/qml/InvokeExample
+
+RESOURCES += qml_resources
 
 STATECHARTS = statemachine.scxml
 
diff --git a/examples/scxml/invoke/invoke.qml b/examples/scxml/invoke/invoke.qml
deleted file mode 100644
index e28a6f2..0000000
--- a/examples/scxml/invoke/invoke.qml
+++ /dev/null
@@ -1,10 +0,0 @@
-// Copyright (C) 2016 The Qt Company Ltd.
-// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
-
-import Directions 1.0
-
-MainView {
-    stateMachine: Directions {
-        running: true
-    }
-}
diff --git a/examples/scxml/invoke/invoke.qrc b/examples/scxml/invoke/invoke.qrc
deleted file mode 100644
index 24c0e89..0000000
--- a/examples/scxml/invoke/invoke.qrc
+++ /dev/null
@@ -1,8 +0,0 @@
-<RCC>
-    <qresource prefix="/">
-        <file>invoke.qml</file>
-        <file alias="MainView.qml">MainView.qml</file>
-        <file alias="SubView.qml">SubView.qml</file>
-        <file alias="Button.qml">Button.qml</file>
-    </qresource>
-</RCC>
diff --git a/examples/scxml/invoke/qmldir b/examples/scxml/invoke/qmldir
new file mode 100644
index 0000000..6816682
--- /dev/null
+++ b/examples/scxml/invoke/qmldir
@@ -0,0 +1,5 @@
+module InvokeExample
+prefer :/qt/qml/InvokeExample/
+Button 1.0 Button.qml
+MainView 1.0 MainView.qml
+SubView 1.0 SubView.qml
diff --git a/examples/scxml/invoke/statemachine.scxml b/examples/scxml/invoke/statemachine.scxml
index 6a0f5a9..bd31dca 100644
--- a/examples/scxml/invoke/statemachine.scxml
+++ b/examples/scxml/invoke/statemachine.scxml
@@ -1,12 +1,12 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <!--
-// Copyright (C) 2016 The Qt Company Ltd.
+// Copyright (C) 2023 The Qt Company Ltd.
 // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
 -->
 <scxml
     xmlns="http://www.w3.org/2005/07/scxml"
     version="1.0"
-    name="Directions"
+    name="DirectionsStateMachine"
     initial="anyplace"
 >
     <state id="anyplace">