LabVIEW Control Reference Handle Guide
In LabVIEW, a Control Reference is a unique value used to identify and manipulate controls. Here are the general steps for using a Control Reference in LabVIEW:
- Get the handle reference for the control: Drag and drop the control onto the Front Panel in the Block Diagram, then right-click on the control and select “Create”->”Control Ref”, and output the handle to a structure for the control reference handle.
- Using control reference handles: In places where controls are needed, control reference handles can be used to manipulate controls. Common operations include retrieving control properties, setting control properties, and registering control callback functions.
- To obtain the properties of a control: Use the “Property Node” to access the control’s properties by connecting the control reference handle to the input of the Property Node, selecting the desired property, and then outputting the property value to the appropriate location.
- Control properties can be set using the “Property Node” in LabVIEW. Simply connect the control reference to the input of the Property Node, choose the desired property to set, and then connect the new property value to the appropriate input terminal.
- Register callback function: The “Register for Events” node allows you to register a callback function to respond to specific control events. Connect the control reference handle to the input of the Register for Events node, then select the event and callback function to register.
It is important to note that control reference handles can only be used in the Block Diagram and within the same window or context as the control. Otherwise, errors may occur.
