Qt Sensors - Explorer QML Example ¶

Demonstrates how to read the meta-data of available sensors.

This example is divided into two parts:

A C++ plugin that provides QML alternatives for QSensorExplorer , QPropertyInfo and QSensorItem C++ classes.

A QML Application that uses the QML types to read the sensor meta-data and present it.

This example is built as an executable with C++ code that runs the QML, but it can also be launched directly using the qmlscene tool. You should build the top-level sensor_explorer project before trying to run this example or it will not be able to find its dependencies.
qmlscene -I . sensor_explorer.qml
										
Above, the -I . parameter adds the current directory as a module import path to locate the Explorer QML module.

Sensor Explorer QML Import ¶

The Sensor Explorer QML import defines the Explorer QML module, exporting QSensorExplorer , QPropertyInfo and QSensorItem C++ classes as QML types. The source code is available in the sensor_explorer/import subdirectory.

Sensor Explorer QML Application ¶

To write a QML application that will use the QML types exposed by the Explorer module, following steps are needed:

Import the Explorer 1.0 declarative plugin:
import Explorer 1.0
											
Create a SensorExplorer QML item:
SensorExplorer {
    id: explorer
}
											
You can retrieve a list of all available sensors using SensorExplorer.availableSensors :
model: explorer.availableSensors
											
The example uses the returned list as a model to populate a view of available sensors.

To retrieve the properties of a sensor, use SensorItem.properties :
propertyList.model = explorer.selectedSensorItem.properties
											
The property list is used as a model for another view that displays the property names and values.

It is possible to edit the values of certain sensor properties. Selecting a writable property value will open an editor. SensorExplorer QML type allows you to pass a new value for a sensor property value as follows:
explorer.selectedSensorItem.changePropertyValue(propertyList.selectedItem, loaderEditor.item.text);
											
Starting and stopping a sensor can be done by setting the SensorItem.start 特性：
if (text === "Start") {
    explorer.selectedSensorItem.start = true;
    text = "Stop";
}
else {
    explorer.selectedSensorItem.start = false;
    text = "Start";
}
											
范例工程 @ code.qt.io

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Qt Sensors - Explorer QML Example ¶

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