[Interest] How to publish a message in QML with Qtmqtt

[Maurice Kalinowski]

Hi,

You seem to be perfectly right that publishing does not work out of the box. This is mostly because of a failing auto-conversion from QString to QMqttTopicName.

The easiest workaround is to apply attached patch, which adds a publish using a QString and do the conversion manually. Feel free to create a bugreport, so that we can take this into consideration when adding a proper qml api for this module.

BR,
Maurice Kalinowski

Von: Interest <interest-bounces+maurice.kalinowski=qt.io at qt-project.org> Im Auftrag von Egg Nine
Gesendet: Sunday, June 17, 2018 9:19 PM
An: interest at qt-project.org
Betreff: [Interest] How to publish a message in QML with Qtmqtt

Hi all,

I am trying to publish an mqtt message using Qt QML following this example:
https://doc.qt.io/QtMQTT/qtmqtt-quicksubscription-example.html

However, this example only shows how to subscribe to topics while I want to publish.
I tried to call "publish" from QML like can see in code below but nothing is sent while console.log shows a -1.

Any thoughts what I am doing wrong? Or does someone has an example?
I can see in my broker log that a connection is made successfully.

    MqttClient {
        id: mqttclient
        port: 1883
        hostname: "localhost"
    }

    Button {
        id: connect
        text: qsTr("Connect")
        onClicked: {
            console.log(mqttclient.connectToHost())
        }
    }

    Button {
        id: publish
         text: qsTr("publish")
        onClicked: {
            console.log(mqttclient.publish("mytopic","mytestmessage"))
        }
    }

Thanks!
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