`addSetting`

Adds a setting, a named value holder, to a settings group.

Category: Environment and Settings > System Commands

Syntax

S = addSetting(G, name)

Creates an empty setting called name in group G.

S = addSetting(G, name, Name, Value)

Creates the setting with options such as 'PersonalValue' and 'ValidationFcn'.

Description

A setting holds up to four layers of value: temporary, personal, installation and factory. Reading S.ActiveValue returns the first one that is set, in that priority order, and errors when none is. Assigning S.PersonalValue or S.TemporaryValue stores a value in that layer and runs the validation function.

A new setting starts with no value in any layer, so give it a personal value before reading it.

Input arguments

G: A SettingsGroup created with addGroup. Settings cannot be added to the root returned by settings.
name: Setting name, with the same naming rules as a group.
'PersonalValue': Initial personal value. It is checked by the validation function, if any.
'ValidationFcn': Function handle called on every assigned value; it should error for invalid values, like @matlab.settings.mustBeNumericScalar.
'Hidden': Logical flag that hides the setting from listings.

Output arguments

S: The new matlab.settings.Setting object.

Example

Setting with validation

s = settings;
g = addGroup(s, 'demo');
a = addSetting(g, 'Size', 'PersonalValue', 10, ...
    'ValidationFcn', @matlab.settings.mustBeNumericScalar);
disp(a.ActiveValue)
a.PersonalValue = 20;
disp(a.ActiveValue)
try
    a.PersonalValue = 'x';
catch err
    disp(['Rejected: ' err.message])
end
removeGroup(s, 'demo');

Output

    10
    20
Rejected: Error setting 'Size' in group 'demo': Value must be numeric.

Notes

In MatLivre, personal values last for the current session only; they are not saved between runs as MATLAB saves them.

addSetting