Add or remove custom publish buttons

The MQTT applet supports up to 12 user-defined publish buttons. Each button sends a fixed payload to a fixed topic when clicked. This page explains how to add new buttons, edit existing ones, and remove buttons you no longer need.

Before you start

• The MQTT applet must be visible. If it is not, click the MQTT tray button on the right sidebar to show it.
• You do not need to be connected to the broker to edit buttons. However, buttons only publish when the applet is connected (status shows "Connected").
• Button definitions are stored in MqttButtons and persist between sessions.

Steps

Add a button

1. In the MQTT applet, click Edit. The button area enters edit mode: existing buttons change appearance and a + tile appears.
2. Click the + tile.
3. In the dialog that opens, enter a label, a topic, and a payload for the new button.
4. Confirm the dialog.
5. Click Done to exit edit mode.

Edit an existing button

1. Click Edit.
2. Click the button you want to change. An edit dialog opens showing the current label, topic, and payload.
3. Change the values as needed and confirm.
4. Click Done.

Remove a button

1. Click Edit.
2. Right-click the button you want to remove.
3. Click Remove in the context menu that appears.
4. Click Done.

What each control does

Control	Default	Notes
Edit / Done	Edit	Toggles edit mode. In edit mode, clicking a button opens the edit dialog; right-clicking shows the Remove option; the + tile is visible.
Publish buttons	—	Each button publishes its configured payload to its configured topic. Active only while connected. Up to 12 buttons. Stored in MqttButtons.
+ tile	—	Visible only in edit mode. Opens the add-button dialog. Disabled once 12 buttons exist.

Tips

• Button tooltips show the target topic and payload when the applet is in normal mode (topic → payload). In edit mode they show the same information prefixed with "Click to edit".
• Buttons are inactive when the applet is disconnected. Connect first, then use the buttons to publish.
• If you need to publish to the same topic with different payloads, create one button per payload.

Troubleshooting

• Clicking a publish button does nothing — The applet is not connected. Check that the status label reads "Connected". If it reads "Disconnected" or an error message, click Enable to connect. See Connect to a station MQTT broker.
• The + tile does not appear — You already have 12 buttons, which is the maximum. Remove at least one button before adding another.
• Button changes are lost after restart — Changes are saved automatically when you confirm the edit dialog. If the applet crashed before saving, the previous MqttButtons value is restored.

Related

• Connect to a station MQTT broker
• Publish a canned message with a button (e.g. rotator preset)
• MQTT overview