Display a reference menu in the panel window. This is a reference to a node in the data base.

## Usage

MenuRef( name, node, par,
ref, refNone=False, tooltip=None,
whatsthis=None, helpURL=None, default=False,
redraw=false )

## Parameters

name (string)
Label of the menu. This is displayed on the left.
node (string)
Data base path of the node containing the parameter.
par (string)
Parameter name. The value of the menu is extracted from this parameter under the above node, and upon change by you, the value is deposited therein.
ref (string)
The path of a node in the data base. The list of items that are displayed in this menu are the children of a node given in ref.
refNone (boolean)
If it's true a ('None','none') will be appear at the head of reference options.
tooltip (string)
Tooltip help information, also known as bubble. The content of this argument is displayed in a small dynamic box placed opened above the menu, when the cursor remains at the menu for short time. This is typically a short phrase.
whatsthis (string)
Whatsthis help information. When you click on the whatsthis icon followed by clicking on this menu, a small box opens above the menu and the content of this argument is displayed in it. This is typically a short sentence or two, which provides more information than that given by the tooltip argument. The whatsthis argument is a rich text format, which means you can embed many of the HTML tags, such as <br> for line separator and <b> for bold.
helpURL (string)
This is the HTML-URL address containing detailed help on the menu item. When you press the F1 key while the cursor is on top of this menu, the assistance help system opens and displays this page.
default (string)
Default value. If the data base does not contain the parameter given by the node and par arguments, it is first initialized to this value.
redraw (boolean)
Flag specifying whether to redraw the panel when you change the value. This allows inclusion of complex menus that dynamically depend on the value of this menu.

None

## Errors

• The parameter in the data base must be of type string.
• The parameter must exist in the data base or the default must not be None.

## Description

This routine places a reference menu in the panel window. The menu contains a label given by the name argument. The displayed value is extracted from the data base node and par. Upon change, the value is deposited back onto the data base. Now, if redraw is True, the entire panel is redrawn. This provides the opportunity to change the other menu selections. The path of the node in data base that this menu is referencing to is given by ref. If refNone is True, "None" will appear at the head of reference options. For example,
nodeTmf = ROOT + RS + 'MULTIPLIER_FUNCTION' + RS + item.name
MenuRef( name = 'Curve Fit Multiplier Function',
tooltip = 'Curve Fit Variable Multiplier Function',
whatsthis= 'Multiplier funntion whose value to be used as\n'
'the independent variable of the curve fit',
helpURL = URL + '#curve_fit_variable_multiplier_function',
node = nodeTmf,
par = 'curve_fit_variable_multiplier_function',
ref = ROOT + RS + 'MULTIPLIER_FUNCTION',
refNone = True,
default = 'none' )