1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135



use {Cursive, Printer, With};
use align::HAlign;
use direction::Direction;
use event::*;
use theme::ColorStyle;
use unicode_width::UnicodeWidthStr;
use vec::Vec2;
use view::View;

/// Simple text label with a callback when <Enter> is pressed.
///
/// A button shows its content in a single line and has a fixed size.
///
/// # Examples
///
/// ```
/// # use cursive::views::Button;
/// let quit_button = Button::new("Quit", |s| s.quit());
/// ```
pub struct Button {
    label: String,
    callback: Callback,
    enabled: bool,
}

impl Button {
    /// Creates a new button with the given content and callback.
    pub fn new<F, S: Into<String>>(label: S, cb: F) -> Self
    where
        F: Fn(&mut Cursive) + 'static,
    {
        Button {
            label: label.into(),
            callback: Callback::from_fn(cb),
            enabled: true,
        }
    }

    /// Sets the function to be called when the button is pressed.
    ///
    /// Replaces the previous callback.
    pub fn set_callback<F>(&mut self, cb: F)
    where
        F: Fn(&mut Cursive) + 'static,
    {
        self.callback = Callback::from_fn(cb);
    }

    /// Disables this view.
    ///
    /// A disabled view cannot be selected.
    pub fn disable(&mut self) {
        self.enabled = false;
    }

    /// Disables this view.
    ///
    /// Chainable variant.
    pub fn disabled(self) -> Self {
        self.with(Self::disable)
    }

    /// Re-enables this view.
    pub fn enable(&mut self) {
        self.enabled = true;
    }

    /// Enable or disable this view.
    pub fn set_enabled(&mut self, enabled: bool) {
        self.enabled = enabled;
    }

    /// Returns `true` if this view is enabled.
    pub fn is_enabled(&self) -> bool {
        self.enabled
    }

    fn req_size(&self) -> Vec2 {
        Vec2::new(2 + self.label.width(), 1)
    }
}

impl View for Button {
    fn draw(&self, printer: &Printer) {
        if printer.size.x == 0 {
            return;
        }

        let style = if !self.enabled {
            ColorStyle::Secondary
        } else if !printer.focused {
            ColorStyle::Primary
        } else {
            ColorStyle::Highlight
        };

        let offset =
            HAlign::Center.get_offset(self.label.len() + 2, printer.size.x);

        printer.with_color(style, |printer| {
            printer.print((offset, 0), &format!("<{}>", self.label));
        });
    }

    fn required_size(&mut self, _: Vec2) -> Vec2 {
        // Meh. Fixed size we are.
        self.req_size()
    }

    fn on_event(&mut self, event: Event) -> EventResult {
        // eprintln!("{:?}", event);
        // eprintln!("{:?}", self.req_size());
        match event {
            // 10 is the ascii code for '\n', that is the return key
            Event::Key(Key::Enter) => {
                EventResult::Consumed(Some(self.callback.clone()))
            }
            Event::Mouse {
                event: MouseEvent::Release(MouseButton::Left),
                position,
                offset,
            } if position.fits_in_rect(offset, self.req_size()) =>
            {
                EventResult::Consumed(Some(self.callback.clone()))
            }
            _ => EventResult::Ignored,
        }
    }

    fn take_focus(&mut self, _: Direction) -> bool {
        self.enabled
    }
}