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++ // Copyright (C) 2023 The Qt Company Ltd.
++ // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
++
++ /*!
++ \example invoke
++ \title SCXML Invoke
++ \examplecategory {Data Processing & I/O}
++ \ingroup examples-qtscxml
++
++ \brief Invokes a compiled nested state machine.
++
++ \image invoke.png
++ {Window with four panels: Go Nowhere, Go Somewhere, Go There,
++ and Go Here}
++
++ \e{Invoke} demonstrates how to use the \c <invoke> element
++ with generated nested state-machines, where the SCXML file is compiled to
++ a C++ class. The \c <invoke> element is used to create an instance of an
++ external service.
++
++ \include examples-run.qdocinc
++
++ \section1 Invoking the State Machine
++
++ In \e statemachine.scxml, we specify a state machine with the name
++ \e DirectionsStateMachine of type \e http://www.w3.org/TR/scxml/ to invoke:
++
++ \quotefromfile invoke/statemachine.scxml
++ \skipto scxml
++ \printuntil
++
++ \section1 Compiling the State Machine
++ We link against the Qt SCXML module by adding the following lines to the
++ example's build files.
++
++ \section2 \e invoke.pro when using qmake:
++
++ \quotefromfile invoke/invoke.pro
++ \skipto QT
++ \printline scxml
++
++ We then specify the state machine to compile:
++ \skipto STATECHARTS
++ \printline scxml
++
++ \section2 \e CMakeLists.txt when using cmake:
++ \quotefromfile invoke/CMakeLists.txt
++ \skipto find_package
++ \printline Scxml
++ \skipto target_link_libraries
++ \printuntil )
++
++ We then specify the state machine to compile:
++ \skipto qt6_add_statecharts
++ \printuntil )
++
++ The statechart directives \e STATECHARTS or \e qt6_add_statecharts invoke the Qt SCXML
++ Compiler, \c qscxmlc, which is run automatically to generate \e statemachine.h and
++ \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 DirectionsStateMachine element in the \e MainView.qml
++ file, as follows:
++
++ \quotefromfile invoke/MainView.qml
++ \skipto DirectionsStateMachine
++ \printuntil }
++ */