Source code for arcade.gui.core

import typing
from typing import Optional, Set, Any
from uuid import uuid4

import arcade
from arcade.gui.ui_style import UIStyle

if typing.TYPE_CHECKING:
    from arcade.gui import UIManager



[docs]class UIEvent: """ Represents an interaction with the gui. """
[docs] def __init__(self, type: str, **kwargs): """ :param type: Type of the event, like :py:attr:`arcade.gui.MOUSE_PRESS` :py:attr:`arcade.gui.KEY_PRESS` :param kwargs: Data of the event """ self.type = type = kwargs self._repr_keys = tuple(kwargs.keys())
[docs] def get(self, key: str) -> Any: """ Retrieve value for given key :param str key """ return
def __str__(self): return ' '.join([f'{self.type} ', *[f'{key}={getattr(self, key)}' for key in self._repr_keys]])
[docs]class UIElement(arcade.Sprite): """ Base class for all UI elements. Implements :py:class:`arcade.Sprite`, requires a texture to be set in :py:meth:`arcade.gui.UIElement.render()` :py:class:`arcade.gui.UIElement` contains an id, which can be used to retrieve it from :py:class:`arcade.gui.UIManager` Holds a reference to a :py:class:`arcade.gui.UIStyle`, resolving values depending on the :py:attr:`UIElement().id`, :py:attr:`UIElement().style_classes`, and element specific style attributes. """
[docs] def __init__(self, center_x=0, center_y=0, id: Optional[str] = None, style: UIStyle = None, **kwargs): super().__init__() # ID for this element, to search in view by id or identify this element from an event self.__id = id self.mng: Optional['UIManager'] = None # unique id, to overwrite style for exactly this element, DONT CHANGE THIS LATER self.__style_id = str(uuid4()) self.style_classes = ['globals'] self._style: UIStyle = style if style else UIStyle.default_style() self._style.push_handlers(self.on_style_change) # what do we need to look like a proper arcade.Sprite # self.texture <- subclass # self.width/height <- subclass self.center_x = center_x self.center_y = center_y
@property def id(self) -> Optional[str]: """ You can set id on creation, but it can't be modify later """ return self.__id @id.setter def id(self, value): if len(self.sprite_lists) > 0: raise UIException('Setting id, after adding to a UIManager, is to late!') self.__id = value @property def style(self) -> UIStyle: """ :return: Referenced :py:class:`arcade.gui.UIStyle` """ return self._style
[docs] def set_style_attrs(self, **kwargs): """ Sets a custom style attribute for this UIElement The value will be returned unparsed (like given) Setting an attribute to None will remove the overwrite, defaults will apply :param kwargs: key-value pairs """ self._style.set_class_attrs(self.__style_id, **kwargs)
def _lookup_classes(self): return [*self.style_classes,, self.__style_id]
[docs] def style_attr(self, key, default=None): """ Resolve a style attribute. :param key: Attribute key :param default: default return if not found. :return: Attribute value or default value if attribute key was not found. """ value = self._style.get_attr(self._lookup_classes(), key) return value if value else default
[docs] def on_style_change(self, style_classes: Set[str]): """ Callback which is used to trigger rerender. Normal subclasses don't have to overwrite this method. """ if style_classes.intersection(set(self._lookup_classes())): self.render()
[docs] def render(self): """ Render and update textures, called on style change. Initially called while added to :py:class:`arcade.gui.UIManager` Has to be implemented by subclasses of :py:class:`arcade.gui.UIElement`. """ raise NotImplementedError()
[docs] def on_ui_event(self, event: UIEvent): """ Callback for a :py:class:`arcade.gui.UIEvent`, triggered through pyglet.EventDispatcher :param UIEvent event: Dispatched event :return: If True is returned the dispatch will stop """ pass
[docs] def on_focus(self): """ Callback if the element gets focused """ pass
[docs] def on_unfocus(self): """ Callback if the element gets unfocused aka is not focused any more """ pass
[docs] def on_hover(self): """ Callback if the element gets hovered """ pass
[docs] def on_unhover(self): """ Callback if the element gets unhovered aka is not focused any more """ pass
[docs]class UIException(Exception): """ Abstract Exception within the UI. """ pass