VI Properties
Requires: Base Package
View the class hierarchy.
You can set these properties for a VI in edit mode by selecting File»VI Properties and other menu items. If you do not wire a refnum to the reference input of the Property Node, LabVIEW gets or sets the property for the current VI.
| Property | Description |
|---|---|
| Auto Logging:Log at Finish | Indicates whether to write front panel values to a datalog file after the VI runs. Details |
| Auto Logging:Log File Path | Path of the datalog file in which front panel data and a time stamp are written. Details |
| Auto Logging:Print at Finish | Indicates whether to print the front panel after the VI runs. Details |
| Auto Preallocate Arrays and Strings | Get or set the Autopreallocate arrays and strings setting on VIs. This is used by the FPGA module to optimize array and string operations by forcing LabVIEW to preallocate memory at compile time rather than dynamically allocating memory at run time. This property is similar to the Autopreallocate arrays and strings checkbox on the Execution Page of the VI Properties dialog box. Details |
| Automatic Error Handling | If TRUE, enables automatic error handling for a VI. Details |
| Block Diagram | Returns a reference to the block diagram of the VI. This property is not available in stand-alone applications. Details |
| Block Diagram Window:Open | Opens or closes the block diagram window. Details |
| Block Diagram Window:Origin | Gets or sets the vertical and horizontal coordinates in the upper left-hand corner of the block diagram. Details |
| Block Diagram Window:State | Current state of the block diagram window. Details |
| Block Diagram Window:Window Bounds | Gets or sets the bounds for a block diagram window. Details |
| C Code Generation:Expression Folding | Generates better performing and more efficient code by collapsing groups of nodes into single expressions that are easily recognized by C compilers. Details |
| C Code Generation:Generate C Function Calls | Generates the calling interface to the VI as C function calls without any default data initializations, which can reduce the code size by as much as 50% for a small VI. If an input to or output from the VI is unwired when you build the VI into an application, the C function call uses the default value for that control or indicator. To generate C function calls using this property, you also must generate serial only code. Details |
| C Code Generation:Generate Guard Code | Generates extra code to prevent common coding mistakes that can cause an application to crash or function incorrectly. For example, guard code can prevent dividing by zero or indexing out of range in an array. Guard code makes an application slightly larger and slower. Details |
| C Code Generation:Generate Integer Only | Generates C code without any floating-point operations. Details |
| C Code Generation:Generate Serial Only | Generates C code without cooperative multitasking code. Removing this cooperative multitasking code makes the C code easier to read and usually runs much faster. However, you lose parallel execution behavior. This execution behavior most closely resembles subroutine priority VIs in LabVIEW software for Windows. Details |
| C Code Generation:Inline SubVI | Inlines subVIs into callers, which can eliminate overhead and increase code optimization. Inlining subVIs is most useful for small subVIs, VIs with many calls in a loop, or subVIs with only one call site. Details |
| C Code Generation:Use Stack Variables | Uses stack variables rather than heap variables to represent signals in the generated C code, which enables better C compiler optimizations and makes the C code faster. Details |
| Callers' Names | Returns a list of all the loaded VIs that call the referenced VI. Details |
| Connector Pane:DataType | Returns the data type of the connector pane as variant data. Connector panes for VIs have a VI data type. Connector panes for polymorphic VIs have a PolyVI data type. Connector panes for custom controls, global variables, and type definitions have the data type of the control. Details |
| Connector Pane:Reference | Returns a reference to the connector pane of the VI. Details |
| Connector Pane:Set | Sets the connector pane of the VI to match the connector pane of the VI reference input. Details |
| Contains Compiled Code | Sets or returns whether a VI includes compiled code. Details |
| Control VI Type | Specifies whether a control VI is a custom control, a typedef, or a strict typedef. This property is valid for control VIs only. Details |
| Edit Mode On Open | If TRUE, the VI opens in edit mode. If FALSE, the VI opens in run mode, and the title bar, menu bar, and toolbar do not appear. Details |
| Execution:Allow Debugging | If TRUE, you can use debugging tools on the VI. Set this property to FALSE to reduce memory requirements and to improve performance slightly for the VI. Details |
| Execution:Close After Call | Indicates whether to close the front panel after the VI runs. Details |
| Execution:Inline Is Allowed | Returns TRUE if you can inline this subVI into its calling VIs. Details |
| Execution:Inline SubVI | Specifies whether to inline the subVI into its calling VIs. Details |
| Execution:Is Reentrant | Indicates whether a VI can be reentrant. Details |
| Execution:Preferred Exec System | Indicates the execution system in which the VI runs. Details |
| Execution:Priority | Indicates the priority of the VI when it runs in parallel with other tasks. Details |
| Execution:Reentrancy Type | Indicates the type of reentrancy LabVIEW uses for a reentrant VI. Details |
| Execution:Run When Opened | Indicates whether to run the VI when it opens. Details |
| Execution:Show Front Panel On Call | Indicates whether to show the front panel when the VI is called. Details |
| Execution:Show Front Panel On Load | Indicates whether to show the front panel when the VI is loaded. Details |
| Execution:State | Indicates the execution state of the VI. Details |
| Execution:Suspend On Call | Indicates whether the VI should be suspended when it is called as a subVI. Use this property carefully with reentrant VIs. Details |
| Expand When Dropped As SubVI | Expands to show terminals when dropped as a subVI. Details |
| Front Panel | Reference to the front panel of a VI. Details |
| Front Panel Window:Allow Runtime PopUp | Indicates whether to display shortcut menus for front panel objects while the VI runs. If you do not display default run-time shortcut menus, you can continue to include customized shortcut menus. Details |
| Front Panel Window:Behavior | Sets the behavior of the front panel window. Valid values include 0 (Invalid), 1 (Default), 2 (Floating), 3 (Floating/Auto-Hide), and 4 (Modal). Details |
| Front Panel Window:Closeable | Indicates whether the close button in the title bar is disabled and the Close item in the File menu is disabled. Details |
| Front Panel Window:Custom Title | Indicates whether the VI has a custom title string. Write FALSE to remove the custom title string. Details |
| Front Panel Window:Highlight Return Button | Indicates whether to highlight Boolean controls that have a shortcut key of <Enter>. Details |
| Front Panel Window:Is Frontmost | Writing TRUE to this value brings the front panel to the front. This property applies only in the application instance of the calling VI. Writing FALSE to this value has no effect. If you read this property, it indicates whether the front panel window is the front window (ignoring floating windows). Details |
| Front Panel Window:Keep Window Proportions | Indicates whether the front panel window adjusts its size in proportion with a change in monitor resolution. The window changes size so it covers the same percentage of the screen that it covered at its original resolution. Details |
| Front Panel Window:Minimizable | Indicates whether the user can minimize the front panel window while the VI runs. Details |
| Front Panel Window:Minimum Size | Minimum size of the front panel window in pixels. If Front Panel Window:Resizable is TRUE, the user cannot resize the front panel smaller than the width and height you wire to this property. Details |
| Front Panel Window:Monitor | The monitor on which the front panel window appears, if you have multiple monitors. The value 1 is the primary monitor. Details |
| Front Panel Window:Open | National Instruments recommends you use the Front Panel:Open method instead of this property to open the front panel window. Reading this property indicates whether the window currently is open. Details |
| Front Panel Window:Panel Bounds | The four elements in the cluster are the top, left, bottom, and right values of the interior portion of the front panel, not including the scroll bars, title bar, menu bar, and toolbar. The cluster elements are in global screen coordinates, which are the numbers that refer to coordinates within a computer monitor's screen (rather than an open window). You can set this property only for VIs with open front panels. If you do not want the VI for which you want to set this property to appear to users, use the Hidden state of the Front Panel Window:State property to hide the front panel of the VI. Details |
| Front Panel Window:Resizable | Indicates whether the user can resize the front panel window while the VI runs. Details |
| Front Panel Window:Run VI Transparently | Sets the VI to use a semi-transparent window style when running. Set the level of transparency using the Front Panel Window:Transparency property. Details |
| Front Panel Window:Show Menu Bar | Indicates whether to display the menu bar on the front panel while the VI runs. Details |
| Front Panel Window:State | Current state of the front panel window. Details |
| Front Panel Window:Title | String that appears in the title bar. This string does not have to match the VI filename. Details |
| Front Panel Window:Title Bar Visible | Indicates whether to display a title bar on the front panel while the VI runs. Details |
| Front Panel Window:Transparency | Sets the window transparency level of the VI. The level of transparency is a percentage where 0 is opaque and 100 is invisible. This property returns an error if you specify a value outside the range of 0 to 100. If you set the transparency level to 100, the VI becomes invisible and uncontrollable from the front panel. You must stop the VI on the block diagram for the front panel of the VI to become visible. You must set the Front Panel Window:Run VI Transparently property to TRUE for this property to have any effect. The default value for the Front Panel Window:Run VI Transparently property is FALSE, in which changing this property has no effect. Details |
| Front Panel Window:Window Bounds | The four elements in the cluster are the top, left, bottom, and right values of the front panel window, which includes the interior region, scroll bars, title bar, menu bar, and toolbar. They are in global screen coordinates, that is, the numbers refer to coordinates within a computer monitor's screen (rather than an open window). You can set this property only for VIs with open front panels. If you do not want the VI for which you want to set this property to appear to users, use the Hidden state of the Front Panel Window:State Property to hide the front panel of the VI. Details |
| Help:Document Path | Path or symbolic path to an HTML file (.htm or .html) or compiled help file (.chm or .hlp) to which the VI is linked. Details |
| Help:Document Tag | Index keyword or HTML filename for a topic in the compiled help file to which the VI is linked. Details |
| History:Always Add Comments At Save | Indicates whether to add a comment to the VI revision history every time the VI is saved. Details |
| History:Entire Text | Returns all the text that was added to the VI revision history. Details |
| History:Prompt for Comments At Close | Indicates whether to prompt for a VI revision history comment when the VI closes. Details |
| History:Prompt for Comments At Save | Indicates whether to prompt for a VI revision history comment when the VI is saved. Details |
| History:Record Application Comments | Indicates whether to add comments to the VI revision history when certain events occur, such as conversion to a new version of LabVIEW, subVI changes, and changes to the name or path of the VI. Details |
| History:Revision Number | Current revision number of the VI. Details |
| History:Use Defaults | Indicates whether to use the global default history or to use the values entered in other history properties. Details |
| Is Clone VI | Returns TRUE if the VI is a clone of a reentrant VI. Details |
| Is In Packed Library | Returns TRUE if a packed project library contains the VI. Details |
| Is Instance | Returns whether or not the VI is an Express VI instance. Details |
| Is Probe | Returns TRUE if the VI is running as a probe and the probe VI is open. Details |
| Is VI Paused? | Specifies whether the execution of the VI is paused. A TRUE value indicates that the VI is paused. A FALSE value indicates that the VI is not paused or that it is not running. Details |
| Library | Returns the name of the LabVIEW project library, XControl, or LabVIEW class that owns the VI. If no library, XControl, or class owns the VI, the property returns Not a Refnum. Details |
| Metrics:Block Diagram Loaded | Specifies whether the block diagram of the VI is in memory. The block diagram can be in memory even if the window is not open. Details |
| Metrics:Code Size | Amount of memory used for VI code in bytes. Details |
| Metrics:Front Panel Loaded | Specifies whether the front panel of the VI is in memory. The front panel can be in memory even if the window is not open. Details |
| Metrics:Size of Block Diagram | Size of the block diagram in bytes. Details |
| Metrics:Size of Front Panel | Size of the front panel in bytes. Details |
| Metrics:Total Data Size | Amount of memory allocated for data in bytes. Details |
| Modifications:Block Diagram Mods Bitset | Indicates whether changes were made to the block diagram since the VI was saved or opened, depending on which was last. If the value is zero, no changes were made. If the value is nonzero, changes were made. Details |
| Modifications:Front Panel Mods Bitset | Indicates whether changes were made to the front panel since the VI was saved. If the value is zero, no changes where made. If the value is nonzero, changes were made. Details |
| Modifications:VI Modifications Bitset | Indicates if changes were made to the VI since the VI was saved. If the value is zero, no changes were made. If the value is nonzero, changes were made. Details |
| Owning Application | Returns a reference to the application that owns the VI. Be sure and close this reference afterward. Details |
| Printing:Block Diagram Scaling? | If TRUE, LabVIEW scales the block diagram to fit on the printed page. Details |
| Printing:Front Panel Scaling? | If TRUE, LabVIEW scales the front panel to fit on the printed page. Details |
| Printing:Header Content:Date Printed? | If TRUE, LabVIEW includes the date printed in the headers for the VI. Use the Printing:Page Headers? property to set whether LabVIEW prints the headers for the VI. Details |
| Printing:Header Content:Modify Date? | If TRUE, LabVIEW includes the last modified date in the headers for the VI. Use the Printing:Page Headers? property to set whether LabVIEW prints the headers for the VI. Details |
| Printing:Header Content:Page Number? | If TRUE, LabVIEW includes the page number in the headers for the VI. Use the Printing:Page Headers? property to set whether LabVIEW prints the headers for the VI. Details |
| Printing:Header Content:VI Icon? | If TRUE, LabVIEW includes the VI icon in the headers for the VI. Use the Printing:Page Headers? property to set whether LabVIEW prints the headers for the VI. Details |
| Printing:Header Content:VI Name? | If TRUE, LabVIEW includes the VI name in the headers for the VI. Use the Printing:Page Headers? property to set whether LabVIEW prints the headers for the VI. Details |
| Printing:Header Content:VI Path? | If TRUE, LabVIEW includes the VI path in the headers for the VI. Use the Printing:Page Headers? property to set whether LabVIEW prints the headers for the VI. Details |
| Printing:Margins | Gets or sets the page margins to use when printing the VI in inches or centimeters. Details |
| Printing:Page Headers? | If TRUE, LabVIEW prints headers for the VI. Use the Printing:Header Content properties in this class to customize the contents of the headers. Details |
| Printing:Page Orientation | Gets or sets the page orientation to use when printing the VI. Details |
| Run-Time Menu Path | When read, this property returns the run-time menu path of the VI. When written, this property updates the run-time menu path of the VI. If the VI is running when you write this property, it updates the menu with data from the new path. Details |
| Terminal Bounds[] | Returns an array of terminal bounds for the connector pane of the referenced VI. The bounds for each terminal are represented as a cluster of integers that indicate the position of each edge of the terminal rectangle. Details |
| Tool Bar:Show Abort Button | Indicates whether to display the Abort Execution button on the toolbar while the VI runs. Details |
| Tool Bar:Show Free Run Button | Indicates whether to display the Run Continuously button on the toolbar while the VI runs. Details |
| Tool Bar:Show Run Button | Indicates whether to display the Run button on the toolbar while the VI runs. Details |
| Tool Bar:Visible | Indicates whether to display the toolbar while the VI runs. Details |
| VI Clone Name | Name of the clone of a reentrant VI. Returns an error if the VI is not a clone. Details |
| VI Description | Description of the VI that appears in the Context Help window when you move the cursor over the VI icon and in VI documentation you generate. Details |
| VI Name | Name of the VI file. If a LabVIEW project library owns the VI, the property returns the qualified name of the VI, which includes the project library filename. Details |
| VI Path | Path to the VI file. Details |
| VI Type | Indicates the type of VI. Details |