Qt SCXML 媒體播放器 QML 範例 (靜態)

A Qt Quick application that sends data to and receives it from a compiled ECMAScript data model.

Media Player QML Example (Static) demonstrates how to access data from an ECMAScript data model that is compiled into a C++ class.

UI 是使用 Qt Quick 創建的。

運行範例

要運行範例從 Qt Creator ，打開歡迎模式，然後選擇範例從範例。更多信息，拜訪構建和運行範例 .

使用 ECMAScript 數據模型

We specify the data model as a value of the datamodel 屬性在 <scxml> element in mediaplayer-common/mediaplayer.scxml :

<scxml
    xmlns="http://www.w3.org/2005/07/scxml"
    version="1.0"
    name="MediaPlayerStateMachine"
    initial="stopped"
    datamodel="ecmascript"
>
    <datamodel>
        <data id="media"/>
    </datamodel>

編譯狀態機

We link against the Qt SCXML module by adding the following line to the .pro 文件：

QT += widgets scxml

接著，指定要編譯的狀態機：

STATECHARTS = ../mediaplayer-common/mediaplayer.scxml

Qt SCXML 編譯器 qscxmlc , is run automatically to generate statemachine.h and statemachine.cpp , and to add them to the HEADERS and SOURCES variables for compilation.

實例化狀態機

We instantiate the generated MediaPlayerStateMachine class in mediaplayer-qml-static.cpp :

#include "mediaplayer.h"
int main(int argc, char *argv[])
{
    QGuiApplication app(argc, argv);
    qmlRegisterType<MediaPlayerStateMachine>("MediaPlayerStateMachine", 1, 0, "MediaPlayerStateMachine");
    QQmlApplicationEngine engine;
    engine.load(QUrl(QStringLiteral("qrc:///mediaplayer-qml-static.qml")));
    if (engine.rootObjects().isEmpty())
        return -1;
    return app.exec();
}

範例工程 @ code.qt.io