from __future__ import annotations import sys from functools import partial from typing import cast if sys.version_info >= (3, 8): from typing import Literal else: from typing_extensions import Literal # pragma: no cover import rich.repr from rich.console import RenderableType from rich.text import Text, TextType from .. import events from ..css._error_tools import friendly_list from ..message import Message from ..reactive import Reactive from ..widgets import Static ButtonVariant = Literal["default", "primary", "success", "warning", "error"] _VALID_BUTTON_VARIANTS = {"default", "primary", "success", "warning", "error"} class InvalidButtonVariant(Exception): pass class Button(Static, can_focus=True): """A simple clickable button.""" DEFAULT_CSS = """ Button { width: auto; min-width: 16; height: 3; background: $panel; color: $text; border: none; border-top: tall $panel-lighten-2; border-bottom: tall $panel-darken-3; content-align: center middle; text-style: bold; } Button.-disabled { opacity: 0.4; text-opacity: 0.7; } Button:focus { text-style: bold reverse; } Button:hover { border-top: tall $panel-lighten-1; background: $panel-darken-2; color: $text; } Button.-active { background: $panel; border-bottom: tall $panel-lighten-2; border-top: tall $panel-darken-2; tint: $background 30%; } /* Primary variant */ Button.-primary { background: $primary; color: $text; border-top: tall $primary-lighten-3; border-bottom: tall $primary-darken-3; } Button.-primary:hover { background: $primary-darken-2; color: $text; border-top: tall $primary-lighten-2; } Button.-primary.-active { background: $primary; border-bottom: tall $primary-lighten-3; border-top: tall $primary-darken-3; } /* Success variant */ Button.-success { background: $success; color: $text; border-top: tall $success-lighten-2; border-bottom: tall $success-darken-3; } Button.-success:hover { background: $success-darken-2; color: $text; } Button.-success.-active { background: $success; border-bottom: tall $success-lighten-2; border-top: tall $success-darken-2; } /* Warning variant */ Button.-warning { background: $warning; color: $text; border-top: tall $warning-lighten-2; border-bottom: tall $warning-darken-3; } Button.-warning:hover { background: $warning-darken-2; color: $text; } Button.-warning.-active { background: $warning; border-bottom: tall $warning-lighten-2; border-top: tall $warning-darken-2; } /* Error variant */ Button.-error { background: $error; color: $text; border-top: tall $error-lighten-2; border-bottom: tall $error-darken-3; } Button.-error:hover { background: $error-darken-1; color: $text; } Button.-error.-active { background: $error; border-bottom: tall $error-lighten-2; border-top: tall $error-darken-2; } """ ACTIVE_EFFECT_DURATION = 0.3 """When buttons are clicked they get the `-active` class for this duration (in seconds)""" class Pressed(Message, bubble=True): @property def button(self) -> Button: return cast(Button, self.sender) def __init__( self, label: TextType | None = None, disabled: bool = False, variant: ButtonVariant = "default", *, name: str | None = None, id: str | None = None, classes: str | None = None, ): """Create a Button widget. Args: label (str): The text that appears within the button. disabled (bool): Whether the button is disabled or not. variant (ButtonVariant): The variant of the button. name: The name of the button. id: The ID of the button in the DOM. classes: The CSS classes of the button. """ super().__init__(name=name, id=id, classes=classes) if label is None: label = self.css_identifier_styled self.label = self.validate_label(label) self.disabled = disabled if disabled: self.add_class("-disabled") self.variant = variant label: Reactive[RenderableType] = Reactive("") variant = Reactive.init("default") disabled = Reactive(False) def __rich_repr__(self) -> rich.repr.Result: yield from super().__rich_repr__() yield "variant", self.variant, "default" yield "disabled", self.disabled, False def watch_mouse_over(self, value: bool) -> None: """Update from CSS if mouse over state changes.""" if self._has_hover_style and not self.disabled: self.app.update_styles(self) def validate_variant(self, variant: str) -> str: if variant not in _VALID_BUTTON_VARIANTS: raise InvalidButtonVariant( f"Valid button variants are {friendly_list(_VALID_BUTTON_VARIANTS)}" ) return variant def watch_variant(self, old_variant: str, variant: str): self.remove_class(f"_{old_variant}") self.add_class(f"-{variant}") def watch_disabled(self, disabled: bool) -> None: self.set_class(disabled, "-disabled") self.can_focus = not disabled def validate_label(self, label: RenderableType) -> RenderableType: """Parse markup for self.label""" if isinstance(label, str): return Text.from_markup(label) return label def render(self) -> RenderableType: label = self.label.copy() label = Text.assemble(" ", label, " ") label.stylize(self.text_style) return label async def _on_click(self, event: events.Click) -> None: event.stop() self.press() def press(self) -> None: """Respond to a button press.""" if self.disabled or not self.display: return # Manage the "active" effect: self._start_active_affect() # ...and let other components know that we've just been clicked: self.emit_no_wait(Button.Pressed(self)) def _start_active_affect(self) -> None: """Start a small animation to show the button was clicked.""" self.add_class("-active") self.set_timer( self.ACTIVE_EFFECT_DURATION, partial(self.remove_class, "-active") ) async def _on_key(self, event: events.Key) -> None: if event.key == "enter" and not self.disabled: self._start_active_affect() await self.emit(Button.Pressed(self)) @classmethod def success( cls, label: TextType | None = None, disabled: bool = False, *, name: str | None = None, id: str | None = None, classes: str | None = None, ) -> Button: """Utility constructor for creating a success Button variant. Args: label (str): The text that appears within the button. disabled (bool): Whether the button is disabled or not. name: The name of the button. id: The ID of the button in the DOM. classes: The CSS classes of the button. Returns: Button: A Button widget of the 'success' variant. """ return Button( label=label, disabled=disabled, variant="success", name=name, id=id, classes=classes, ) @classmethod def warning( cls, label: TextType | None = None, disabled: bool = False, *, name: str | None = None, id: str | None = None, classes: str | None = None, ) -> Button: """Utility constructor for creating a warning Button variant. Args: label (str): The text that appears within the button. disabled (bool): Whether the button is disabled or not. name: The name of the button. id: The ID of the button in the DOM. classes: The CSS classes of the button. Returns: Button: A Button widget of the 'warning' variant. """ return Button( label=label, disabled=disabled, variant="warning", name=name, id=id, classes=classes, ) @classmethod def error( cls, label: TextType | None = None, disabled: bool = False, *, name: str | None = None, id: str | None = None, classes: str | None = None, ) -> Button: """Utility constructor for creating an error Button variant. Args: label (str): The text that appears within the button. disabled (bool): Whether the button is disabled or not. name: The name of the button. id: The ID of the button in the DOM. classes: The CSS classes of the button. Returns: Button: A Button widget of the 'error' variant. """ return Button( label=label, disabled=disabled, variant="error", name=name, id=id, classes=classes, )