Crate rat_focus 

This crate is a part of rat-salsa.

For examples see rat-focus GitHub.

• Changes

Focus handling for ratatui

This crate works by adding a FocusFlag to each widget’s state.

Then FocusBuilder is used to collect an ordered list of all widgets that should be considered for focus handling. It builds the Focus which has the functions next, prev and focus_at that can do the navigation.

from <focus_input1.rs>

fn focus_input(state: &mut State) -> Focus {
    let mut fb = FocusBuilder::default();
    fb.widget(&state.input1);
    fb.widget(&state.input2);
    fb.widget(&state.input3);
    fb.widget(&state.input4);
    fb.build()
}

fn handle_input(
    event: &crossterm::event::Event,
    _data: &mut Data,
    _istate: &mut MiniSalsaState,
    state: &mut State,
) -> Result<Outcome, anyhow::Error> {

    // Handle events for focus.
    let f = focus_input(state).handle(event, Regular);

    // ...

    Ok(f)
}

• Keeps the focus-state close to the widgets code.
• Rebuilt for each event.
  • No need to update the widget list when the application state changes.
  • FocusBuilder can be passed on all over the application to build the widget tree.

Modules

doc

Documentation details.

ratatui

Reexport of types used by a macro.

Macros

impl_has_focus

Create the implementation of HasFocus for the given list of struct members.

match_focus

Does a match on several fields and can return a result. Does a widget_state.is_focused() for each field and returns the first that is true. There is an else branch too.

on_gained

Does a match on the state struct of a widget. If widget_state.gained_focus() is true the block is executed. This requires that widget_state implements HasFocus, but that’s the basic requirement for this whole crate.

on_lost

Does a match on the state struct of a widget. If widget_state.lost_focus() is true the block is executed. This requires that widget_state implements HasFocus, but that’s the basic requirement for this whole crate.

Structs

Focus

Focus deals with all focus-related issues.

FocusBuilder

Builder for the Focus.

FocusFlag

Holds the flags for the focus.

Enums

Navigation

Focus navigation for widgets.

Traits

HasFocus

Trait for a widget that takes part of focus handling.

Functions

handle_focus

Handle all events.