Informs users while preserving the current page state.
## Basic usage
Dialog pops up a dialog box, and it's quite customizable.
:::demo Set `model-value / v-model` attribute with a `Boolean`, and Dialog shows when it is `true`. The Dialog has two parts: `body` and `footer`, and the latter requires a `slot` named `footer`. The optional `title` attribute (empty by default) is for defining a title. Finally, this example demonstrates how `before-close` is used.
dialog/basic-usage
:::
:::tip
`before-close` only works when user clicks the close icon or the backdrop. If you have buttons that close the Dialog in the `footer` named slot, you can add what you would do with `before-close` in the buttons' click event handler.
The `header` slot can be used to customize the area where the title is displayed. In order to maintain accessibility, use the `title` attribute in addition to using this slot, or use the `titleId` slot property to specify which element should be read out as the dialog title.
:::demo Normally we do not recommend using nested Dialog. If you need multiple Dialogs rendered on the page, you can simply flat them so that they're siblings to each other. If you must nest a Dialog inside another Dialog, set `append-to-body` of the nested Dialog to true, and it will append to body instead of its parent node, so both Dialogs can be correctly rendered.
dialog/nested-dialog
:::
## Centered content
Dialog's content can be centered.
:::demo Setting `center` to `true` will center dialog's header and footer horizontally. `center` only affects Dialog's header and footer. The body of Dialog can be anything, so sometimes it may not look good when centered. You need to write some CSS if you wish to center the body as well.
dialog/centered-content
:::
:::tip
The content of Dialog is lazily rendered, which means the default slot is not rendered onto the DOM until it is firstly opened. Therefore, if you need to perform a DOM manipulation or access a component using `ref`, do it in the `open` event callback.
:::demo Setting `align-center` to `true` will center the dialog both horizontally and vertically. The prop `top` will not work at the same time because the dialog is vertically centered in a flexbox.
When this is feature is enabled, the content under default slot will be destroyed with a `v-if` directive. Enable this when you have perf concerns.
:::demo Note that by enabling this feature, the content will not be rendered before `transition.beforeEnter` dispatched, there will only be `overlay``header(if any)``footer(if any)`.
When using `modal` = false, please make sure that `append-to-body` was set to **true**, because `Dialog` was positioned by `position: relative`, when `modal` gets removed, `Dialog` will position itself based on the current position in the DOM, instead of `Document.Body`, thus the style will be messed up.
