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**STRUCT**
# `NavigationView`
A page-based navigation container.
<picture><source srcset="navigation-view-dark.png" media="(prefers-color-scheme: dark)"><img src="navigation-view.png" alt="navigation-view"></picture>
`AdwNavigationView` presents one child at a time, similar to
[class@Gtk.Stack].
`AdwNavigationView` can only contain [class@NavigationPage] children.
It maintains a navigation stack that can be controlled with
[method@NavigationView.push] and [method@NavigationView.pop]. The whole
navigation stack can also be replaced using [method@NavigationView.replace].
`AdwNavigationView` allows to manage pages statically or dynamically.
Static pages can be added using the [method@NavigationView.add] method. The
`AdwNavigationView` will keep a reference to these pages, but they aren't
accessible to the user until [method@NavigationView.push] is called (except
for the first page, which is pushed automatically). Use the
[method@NavigationView.remove] method to remove them. This is useful for
applications that have a small number of unique pages and just need
navigation between them.
Dynamic pages are automatically destroyed once they are popped off the
navigation stack. To add a page like this, push it using the
[method@NavigationView.push] method without calling
[method@NavigationView.add] first.
## Tags
Static pages, as well as any pages in the navigation stack, can be accessed
by their [property@NavigationPage:tag]. For example,
[method@NavigationView.push_by_tag] can be used to push a static page that's
not in the navigation stack without having to keep a reference to it manually.
## Header Bar Integration
When used inside `AdwNavigationView`, [class@HeaderBar] will automatically
display a back button that can be used to go back to the previous page when
possible. The button also has a context menu, allowing to pop multiple pages
at once, potentially across multiple navigation views.
Set [property@HeaderBar:show-back-button] to `FALSE` to disable this behavior
if it's unwanted.
`AdwHeaderBar` will also display the title of the `AdwNavigationPage` it's
placed into, so most applications shouldn't need to customize it at all.
## Shortcuts and Gestures
`AdwNavigationView` supports the following shortcuts for going to the
previous page:
- <kbd>Escape</kbd> (unless [property@NavigationView:pop-on-escape] is set to
`FALSE`)
- <kbd>Alt</kbd>+<kbd></kbd>
- Back mouse button
Additionally, it supports interactive gestures:
- One-finger swipe towards the right on touchscreens
- Scrolling towards the right on touchpads (usually two-finger swipe)
These gestures have transitions enabled regardless of the
[property@NavigationView:animate-transitions] value.
Applications can also enable shortcuts for pushing another page onto the
navigation stack via connecting to the [signal@NavigationView::get-next-page]
signal, in that case the following shortcuts are supported:
- <kbd>Alt</kbd>+<kbd></kbd>
- Forward mouse button
- Swipe/scrolling towards the left
For right-to-left locales, the gestures and shortcuts are reversed.
[property@NavigationPage:can-pop] can be used to disable them, along with the
header bar back buttons.
## Actions
`AdwNavigationView` defines actions for controlling the navigation stack.
actions for controlling the navigation stack:
- `navigation.push` takes a string parameter specifying the tag of the page to
push, and is equivalent to calling [method@NavigationView.push_by_tag].
- `navigation.pop` doesn't take any parameters and pops the current page from
the navigation stack, equivalent to calling [method@NavigationView.pop].
## `AdwNavigationView` as `GtkBuildable`
`AdwNavigationView` allows to add pages as children, equivalent to using the
[method@NavigationView.add] method.
Example of an `AdwNavigationView` UI definition:
```xml
<object class="AdwNavigationView"><child><object class="AdwNavigationPage"><property name="title" translatable="yes">Page 1</property><property name="child"><object class="AdwToolbarView"><child type="top"><object class="AdwHeaderBar"/></child><property name="content"><object class="GtkButton"><property name="label" translatable="yes">Open Page 2</property><property name="halign">center</property><property name="valign">center</property><property name="action-name">navigation.push</property><property name="action-target">'page-2'</property><style><class name="pill"/></style></object></property></object></property></object></child><child><object class="AdwNavigationPage"><property name="title" translatable="yes">Page 2</property><property name="tag">page-2</property><property name="child"><object class="AdwToolbarView"><child type="top"><object class="AdwHeaderBar"/></child><property name="content"><!-- ... --></property></object></property></object></child></object>
```
<picture><source srcset="navigation-view-example-dark.png" media="(prefers-color-scheme: dark)"><img src="navigation-view-example.png" alt="navigation-view-example"></picture>
## CSS nodes
`AdwNavigationView` has a single CSS node with the name `navigation-view`.
## Accessibility
`AdwNavigationView` uses the `GTK_ACCESSIBLE_ROLE_GROUP` role.
## Properties
### `updateFunctions`
Additional update functions for type extensions.
### `appearFunctions`
Additional appear functions for type extensions.
### `animateTransitions`
Whether to animate page transitions.
Gesture-based transitions are always animated.
### `popOnEscape`
Whether pressing Escape pops the current page.
Applications using `AdwNavigationView` to implement a browser may want to
disable it.
### `getNextPage`
Emitted when a push shortcut or a gesture is triggered.
To support the push shortcuts and gestures, the application is expected to
return the page to push in the handler.
This signal can be emitted multiple times for the gestures, for example
when the gesture is cancelled by the user. As such, the application must
not make any irreversible changes in the handler, such as removing the page
from a forward stack.
Instead, it should be done in the [signal@NavigationView::pushed] handler.
### `popped`
Emitted after @page has been popped from the navigation stack.
See [method@NavigationView.pop].
When using [method@NavigationView.pop_to_page] or
[method@NavigationView.pop_to_tag], this signal is emitted for each of the
popped pages.
### `pushed`
Emitted after a page has been pushed to the navigation stack.
See [method@NavigationView.push].
### `replaced`
Emitted after the navigation stack has been replaced.
See [method@NavigationView.replace].
### `app`
The application.
### `window`
The window.
## Methods
### `init()`
Initialize `NavigationView`.
### `container(modifiers:)`
Get the widget's view storage.
- Parameter modifiers: The view modifiers.
- Returns: The view storage.
### `update(_:modifiers:updateProperties:)`
Update the widget's view storage.
- Parameters:
- storage: The view storage.
- modifiers: The view modifiers.
- updateProperties: Whether to update the view's properties.
### `animateTransitions(_:)`
Whether to animate page transitions.
Gesture-based transitions are always animated.
### `popOnEscape(_:)`
Whether pressing Escape pops the current page.
Applications using `AdwNavigationView` to implement a browser may want to
disable it.
### `getNextPage(_:)`
Emitted when a push shortcut or a gesture is triggered.
To support the push shortcuts and gestures, the application is expected to
return the page to push in the handler.
This signal can be emitted multiple times for the gestures, for example
when the gesture is cancelled by the user. As such, the application must
not make any irreversible changes in the handler, such as removing the page
from a forward stack.
Instead, it should be done in the [signal@NavigationView::pushed] handler.
### `popped(_:)`
Emitted after @page has been popped from the navigation stack.
See [method@NavigationView.pop].
When using [method@NavigationView.pop_to_page] or
[method@NavigationView.pop_to_tag], this signal is emitted for each of the
popped pages.
### `pushed(_:)`
Emitted after a page has been pushed to the navigation stack.
See [method@NavigationView.push].
### `replaced(_:)`
Emitted after the navigation stack has been replaced.
See [method@NavigationView.replace].