The 'value' property

0 or 1 for Check, Radio ToolButton or Menu
An integer scalar or vector for a List or Combo
An integer scalar for a Selector, Spinner or Trackbar
An integer vector for Scroll or Progress
An integer scalar for a Tree
For a Grid, a character vector or numeric scalar for each cell.

Valid for: List, Combo, Check, Radio, ToolButton, Menu, Scroll, Progress, Selector, Tree
Cell property for a Grid object

The value property contains the current selected value of the control to which it relates. For a Menu item, Check box, Radio button or ToolButton, this is 0 if the control is not selected and 1 if it is selected. If you set a Radio button's or ToolButton's value to 1, any other Radio button or ToolButton in the same group is switched off, and an onClick event is generated. Setting the value property of a Check box to 0 or 1 also generates an onClick event.

For a List or Combo, the value property contains the number (in index origin 1) of the selected item or items (if any). For a single-select list box, it is a vector of length 0 (if no item is selected) or 1 (if an item is selected). For a multi-select list box, it is a vector of arbitrary length. Again, setting the value property of a List generates an onClick event.

For a Spinner or Trackbar, the value property is an integer scalar representing the currently-selected value.

For a Selector, the value property holds the index (starting at 1) of the currently-displayed page, or 0 if none.

For a Tree object, the value property holds the ID of the currently-selected node

For a Progress or Scroll bar, the value property is a four- or five-element vector, as follows

[1] Current value (initially 0)
[2] Maximum value (default 100)
[3] 'Page' increment (default 1)
[4] Minimum value (default 0)
[5] Scroll bar only (Reserved: 0)

When setting this property, you do not have to set all elements.

Grid object value cell property

When you read this cell property for a Grid object, it returns a character vector for each Text cell and a numeric scalar for each Numeric cell, for each cell in the list of rows and columns specified. If a Numeric cell is invalid, it will return the current conversionerrorvalue. If you read a set of cells some of which are Numeric and some Text, it will return a nested array containing a mixture of character vectors and numeric scalars. If you read a set of cells all of which are Numeric, it will return a simple numeric array.

When you write to this cell property for a Grid object, it sets the value for each cell in the list of rows and columns specified. If you supply a number for a cell, that cell becomes a Numeric cell. If you supply a character vector or scalar, it becomes a Text cell. Writing to a cell also causes its valid property to be set to 1.

Although value is a cell property for a Grid object, as a convenience you can read (but not write to) value as a simple property of the Grid object. It returns the value of the currently-active cell. If the cell is a text cell, it will return a character vector. If it is a numeric cell, it will return the numeric value of the cell, or (if the cell is invalid) the current conversionerrorvalue.