Button

system:button

Runs a client callback, opens a URL or sends a string to the server.

Nodes are written into the body or children of a resource pack card template. Besides their own fields, all nodes share id, style, when, unless and repeat; see Common node fields.

JSON fields

Field	Type	Required	Default	Description
type	Resource ID	yes	—	system:button
value	String	no	""	The value or expression used by this type.
click	String	no	""	Button behavior: link, return-val or local.
text	String	no	""	Display text; supports {{parameter_name}} placeholders.
label	String	no	""	Label used for text or the accessible name.
icon	String	no	""	FTB icon parameter key or button icon name.
selected	String	no	""	State key that controls the selected state of the button.
disabled	String	no	""	State key that controls the disabled state of the button.
binding	String	no	""	Optional host action binding.
behavior	String	no	"replace"	Display behavior after the business action completes: close, wait, replace, push.
children	Card node array	no	[]	Child node array.

The example strings only demonstrate the transport form; the server must register the corresponding parsing logic. When reusing an existing button, prefer reading the actions snapshot; for behavior and permissions see Common interaction conventions.

JSON example

{
  "type": "system:button",
  "text": "View details",
  "click": "return-val",
  "value": "example:details reference-123"
}

Placed in the body of a card template or the children of a container. Placeholders come from server snapshots and client build events; changing only the JSON does not produce the missing data or business handlers.

Java entry point

com.iafenvoy.system.screen.card.node.interaction.ButtonNode. This page is based on the Codec in the current 26.1.2 source.