MethodNode QML Type▲
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Import Statement: import QtOpcUa
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Since:: QtOpcUa 5.12
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Inherits:: Node
Detailed Description▲
This QML element supports calling method nodes on a server. The target object node ID has to be specified by the objectNodeId property.
import QtOpcUa as QtOpcUa
QtOpcUa.MethodNode {
nodeId : QtOpcUa.NodeId {
identifier: "s=Example.Method"
ns: "Example Namespace"
}
objectNodeId : QtOpcUa.NodeId {
identifier: "s=Example.Object"
ns: "Example Namespace"
}
connection: myConnection
}The actual function call can be triggered by a signal.
Button {
text: "Start"
onClicked: myNode.callMethod
}or by JavaScript
myNode.callMethod()Property Documentation▲
inputArguments : list<MethodArgument>▲
Arguments to be used when calling the method on the server.
This example shows how to call a method with two double arguments.
QtOpcUa.MethodNode {
...
inputArguments: [
QtOpcUa.MethodArgument {
value: 3
type: QtOpcUa.Constants.Double
},
QtOpcUa.MethodArgument {
value: 4
type: QtOpcUa.Constants.Double
}
]
}See Also▲
See also callMethod
objectNodeId : OpcUaNode▲
Determines the actual node on which the method is called. It can be a relative or absolute node Id.
[read-only] outputArguments : list<var>▲
Returns values from the method call. Depending on the output arguments, this list may contain zero or more values. The resultStatus has to be checked separately. In case the method call failed, the list will be empty.
if (node.status.isGood) {
// print two arguments
console.log("Number of return values:", node.outputArguments.length)
console.log("Return value #1:", node.outputArguments[0])
console.log("Return value #2:", node.outputArguments[1])
}See Also▲
See also callMethod, resultStatus
[read-only] resultStatus : Status▲
Status of the last method call. This property has to be checked to determine if the method call was successful.
See Also▲
See also Status
type : QOpcUa::Types▲
Sets the type of the argument that is expected by the server. The value variant is converted to that type when calling the method. The type has to match the method on the server exactly, otherwise the method call will fail.
See Also▲
See also MethodNode::callMethod