Struct tui_tree_widget::TreeState

pub struct TreeState<Identifier> { /* private fields */ }

Keeps the state of what is currently selected and what was opened in a Tree.

The generic argument Identifier is used to keep the state like the currently selected or opened TreeItems in the TreeState. For more information see TreeItem.

Example

type Identifier = usize;

let mut state = TreeState::<Identifier>::default();

Implementations

impl<Identifier> State<Identifier>

where Identifier: Clone + PartialEq + Eq + Hash,

pub const fn get_offset(&self) -> usize

pub fn get_all_opened(&self) -> Vec<Vec<Identifier>>

pub fn flatten<'a>( &self, items: &'a [Item<'a, Identifier>] ) -> Vec<Flattened<'a, Identifier>>

Get a flat list of all visible (= below open) TreeItems with this TreeState.

pub fn selected(&self) -> Vec<Identifier>

pub fn select(&mut self, identifier: Vec<Identifier>) -> bool

Selects the given identifier.

Returns true when the selection changed.

Clear the selection by passing an empty identifier vector:

state.select(Vec::new());

pub fn open(&mut self, identifier: Vec<Identifier>) -> bool

Open a tree node. Returns true if the node was closed and has been opened. Returns false if the node was already open.

pub fn close(&mut self, identifier: &[Identifier]) -> bool

Close a tree node. Returns true if the node was open and has been closed. Returns false if the node was already closed.

pub fn toggle(&mut self, identifier: Vec<Identifier>)

Toggles a tree node. If the node is in opened then it calls close. Otherwise it calls open.

pub fn toggle_selected(&mut self)

Toggles the currently selected tree node. See also toggle

pub fn close_all(&mut self)

pub fn select_first(&mut self, items: &[Item<'_, Identifier>]) -> bool

Select the first node.

Returns true when the selection changed.

pub fn select_last(&mut self, items: &[Item<'_, Identifier>]) -> bool

Select the last visible node.

Returns true when the selection changed.

pub fn select_visible_index( &mut self, items: &[Item<'_, Identifier>], new_index: usize ) -> bool

Select the node visible on the given index.

Returns true when the selection changed.

This can be useful for mouse clicks.

pub fn select_visible_relative<F>( &mut self, items: &[Item<'_, Identifier>], change_function: F ) -> bool

where F: FnOnce(Option<usize>) -> usize,

Move the current selection with the direction/amount by the given function.

Returns true when the selection changed.

Example

// Move the selection one down
state.select_visible_relative(&items, |current| {
    current.map_or(0, |current| current.saturating_add(1))
});

For more examples take a look into the source code of key_up or key_down. They are implemented with this method.

pub fn scroll_selected_into_view(&mut self)

Ensure the selected TreeItem is visible on next render

pub fn scroll_up(&mut self, lines: usize)

Scroll the specified amount of lines up

pub fn scroll_down(&mut self, lines: usize)

Scroll the specified amount of lines down

pub fn key_up(&mut self, items: &[Item<'_, Identifier>])

Handles the up arrow key. Moves up in the current depth or to its parent.

pub fn key_down(&mut self, items: &[Item<'_, Identifier>])

Handles the down arrow key. Moves down in the current depth or into a child node.

pub fn key_left(&mut self)

Handles the left arrow key. Closes the currently selected or moves to its parent.

pub fn key_right(&mut self)

Handles the right arrow key. Opens the currently selected.

Trait Implementations

impl<Identifier: Clone> Clone for State<Identifier>

fn clone(&self) -> State<Identifier>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<Identifier: Debug> Debug for State<Identifier>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<Identifier: Default> Default for State<Identifier>

fn default() -> State<Identifier>

Returns the “default value” for a type.