ENiGMA½ supports a variety of MCI codes. Some **predefined** codes produce information about the current user, system, or other statistics while others are used to instantiate a **View**.
## General Information
MCI codes are composed of two characters and are prefixed with a percent (%) symbol.
:information_source: To explicitly tie a MCI to a specific View ID, suffix the MCI code with a number. For example: `%BN1`.
:information_source: Standard (non-focus) and focus colors are set by placing duplicate codes back to back in art files:
Some MCI codes have additional options that may be set directly from the code itself while others -- and more advanced options -- are controlled via the current theme.
## Relationship with Menus, Art, and Themes
A MCI code that appears in a `menu.hjson` entry corresponds to that found in it's associated art file. This same MCI code can be referenced in the `theme.hjson` in order to apply a theme.
See [Menus](../docs/configuration/menu-hjson.md) and [Themes](themes.md) for more information.
## Predefined Codes
There are many predefined MCI codes that can be used anywhere on the system (placed in any art file).
| `XY` | A special code that may be utilized for placement identification when creating menus or to extend an otherwise empty space in an art file down the screen. |
| `TM` | Toggle Menu | A toggle menu | Commonly used for Yes/No style input |
| `KE` | Key Entry | A *single* key input control | Think hotkeys |
:information_source: Peek at [/core/mci_view_factory.js](https://github.com/NuSkooler/enigma-bbs/blob/master/core/mci_view_factory.js) to see additional information.
### Mask Edits
Mask Edits (`%ME`) use the special `maskPattern` property to control a _mask_. This can be useful for gathering dates, phone numbers, so on.
`maskPattern`'s can be composed of the following characters:
*`#`: Numeric 0-9
*`A`: Alpha a-z, A-Z
*`@`: Alphanumeric (combination of the previous patterns)
*`&`: Any "printable" character
Any other characters are literals.
An example of a mask for a date may look like this: `##/##/####`.
Additionally, the following theme stylers can be applied:
*`styleSGR1`: Controls literal character colors for non-focused controls
*`styleSGR2`: Controls literal character colors for focused controls
*`styleSGR3`: Controls fill colors (characters that have not yet received input).
All of the style properties can take pipe codes such as `|00|08`.
As mentioned above, MCI codes can (and often should) be explicitly tied to a *View Identifier*. Simply speaking this is a number representing the particular view. These can be useful to reference in code, apply themes, etc.
Predefined MCI codes and other Views can have properties set via `menu.hjson` and further *themed* via `theme.hjson`. See [Themes](themes.md) for more information on this subject.
These are just a few of the properties set on various views. *Use the source Luke*, as well as taking a look at the default `menu.hjson` and `theme.hjson` files!
Often a module will provide custom properties that receive format objects (See **Entry Formatting** below). Custom property formatting can be declared in the `config` block. For example, `browseInfoFormat10`..._N_ (where _N_ is up to 99) in the `file_area_list` module received a fairly extensive format object that contains `{fileName}`, `{estReleaseYear}`, etc.
Various strings can be formatted using a syntax that allows width & precision specifiers, text styling, etc. Depending on the context, various elements can be referenced by `{name}`. Additional text styles can be supplied as well. The syntax is largely modeled after Python's [string format mini language](https://docs.python.org/3/library/string.html#format-specification-mini-language).
Suppose a format object contains the following elements: `userName` and `affils`. We could create a `itemFormat` entry that builds a item to our specifications: `|04{userName!styleFirstLower} |08- |13{affils}`. This may produce a string such as this:
:bulb: Remember that a Python [string format mini language](https://docs.python.org/3/library/string.html#format-specification-mini-language) style syntax is available for widths, alignment, number prevision, etc. as well. A number can be made to be more human readable for example: `{byteSize:,}` may yield "1,123,456".
