Qt SCXML Media Player Example (Dynamic)#

A widget-based application that sends data to and receives it from a dynamically loaded ECMAScript data model.

../_images/mediaplayer.png

Media Player Example (Dynamic) demonstrates how to access data from a dynamically loaded ECMAScript data model.

The UI is created using Qt Widgets.

Running the Example#

To run the example from Qt Creator , open the Welcome mode and select the example from Examples. For more information, visit Building and Running an Example.

Using the ECMAScript Data Model#

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

Dynamically Loading the State Machine#

We link against the Qt SCXML module by adding the following line to the project build files.

With qmake to the mediaplayer-widgets-dynamic.pro

With cmake to the CMakeLists.txt

We dynamically create and instantiate the state machine in mediaplayer-wigdets-dynamic/mediaplayer-widgets-dynamic.cpp:

Connecting to States#

The media player state machine will send out events when users tap a control and when playback starts or stops, as specified in the SCXML file:

To be notified when a state machine sends out an event, we connect to the corresponding signals:

Example project @ code.qt.io