# Button commands
Buttons that act without a line of the page's script: copy a value, print the page, switch the theme, share an address. Each carries its command in `command` and names what it acts on in `aria-controls`, as [`--toggle`](collapse.md) does - no `commandfor`.
## Copy
`command="--copy"` copies its `data-copy`, or the value of the field `aria-controls` names, or that element's text. It says politely that it did - the page's texts `copy.done` and `copy.failed` - and shows a check in place of its icon for a moment; the page hears `redz:copy` with `detail.text`. A page served over plain http has no Clipboard API: the browser's copy command stands in.
```html
```
## Print
`command="--print"` prints the page. However printing starts - the button, the browser's menu, a key - every closed `details`, an accordion's item among them, and every region a `--toggle` button holds closed open for the paper and close again after. A card is not cut across two pages, and a scrolling card's body prints whole; the shell, toasts, the save bar and anything with `print:d-none` stay off the paper.
```html
```
## Theme
Buttons with `command="--theme"` and the value `light`, `dark` or `system` set the page's theme - `data-theme` on `html`, removed for system - and `aria-pressed` says which shows. One button with the value `toggle` flips the theme shown between light and dark, the system's read from `prefers-color-scheme`: it is pressed while dark, so its words name the dark theme. The page hears `redz:theme` with `detail.theme` and keeps the choice - in a cookie, in the account - and writes `data-theme` on `html` on its server, so the page paints in its theme at once.
```html
```
## Share
`command="--share"` shares `data-share-url` - the page's own address when it has none - and `data-share-title` through the device's share sheet where it has one, as a phone does. Elsewhere it opens its menu, `aria-controls`, whose links the library writes by their class: `share-telegram`, `share-facebook`, `share-messenger`, `share-linkedin`, `share-vk`, `share-line` and `share-whatsapp`; a `--copy` item without `data-copy` copies the address. Each class gives its icon the network's colour; Bootstrap Icons has no VK mark, so `share-vk` draws its letters. Messenger opens its app, on a phone.
```html
```
## Keyboard and accessibility
- Each command is a `button`: `Enter` and `Space` run it, and one that is `aria-disabled` does nothing.
- A copy is said once, politely, inside an open modal dialog when there is one; the check that shows for a moment is not read out.
- The theme buttons say which theme shows in `aria-pressed`; the one toggle is pressed while dark, its words the dark theme's.
- The share menu is a [menu](menu.md): it opens on its first link, the arrow keys move through it, and `Escape` closes it back to its button, which says in `aria-expanded` whether it is open.
## Texts
The library has no words of its own; it reads these from the page's island `#redz-ui-text`.
| Key | For | In English |
| --- | --- | --- |
| `copy.done` | Said when a copy is done | Copied |
| `copy.failed` | Said when the browser refuses it | Could not copy |