确定消息框

有关图形用户界面系统的介绍，请参见 图形用户界面概念 。

此示例说明如何弹出一个快速消息框，供用户使用 arcade.gui.OKMessagebox 班级。

gui_ok_messagebox.py

"""
Example code showing how to use the OKMessageBox

If Python and Arcade are installed, this example can be run from the command line with:
python -m arcade.examples.gui_ok_messagebox
"""
import arcade
import arcade.gui
import arcade.gui.widgets.buttons
import arcade.gui.widgets.layout
from arcade.gui import UIOnClickEvent
from arcade.gui.events import UIOnActionEvent


class MyView(arcade.View):
    def __init__(self):
        super().__init__()
        # Create and enable the UIManager
        self.ui = arcade.gui.UIManager()

        # Create a box group to align the 'open' button in the center
        self.v_box = arcade.gui.widgets.layout.UIBoxLayout()

        # Create a button. We'll click on this to open our window.
        show_message_box_button = arcade.gui.widgets.buttons.UIFlatButton(
            text="Show Message Box", width=300
        )
        # Create a label to show the user's choices
        self.last_choice = arcade.gui.UILabel(
            text="",
            align="left", width=300
        )

        # Add both widgets to the v_box to center them
        self.v_box.add(show_message_box_button)
        self.v_box.add(self.last_choice)

        # Add a hook to run when we click on the button.
        show_message_box_button.on_click = self.on_click_open
        self.open_message_box_button = show_message_box_button

        # Create a widget to hold the v_box widget, that will center the buttons
        ui_anchor_layout = arcade.gui.widgets.layout.UIAnchorLayout()
        ui_anchor_layout.add(child=self.v_box, anchor_x="center_x", anchor_y="center_y")
        self.ui.add(ui_anchor_layout)

    def on_click_open(self, _: UIOnClickEvent):
        # The code in this function is run when we click the ok button.
        # The code below opens the message box and auto-dismisses it when done.
        message_box = arcade.gui.UIMessageBox(
            width=300,
            height=200,
            message_text=(
                "Which option do you choose?"
            ),
            buttons=["Ok", "Cancel"],
        )

        @message_box.event("on_action")
        def on_message_box_close(e: UIOnActionEvent):
            # Update the last_choice display
            self.last_choice.text = f"User pressed {e.action}."
            self.last_choice.fit_content()  # Important! Update the layout!

            # show open button and allow interaction again
            self.open_message_box_button.visible = True

        # hide open button and prevent interaction
        self.open_message_box_button.visible = False

        self.ui.add(message_box)

    def on_show_view(self):
        self.window.background_color = arcade.color.DARK_BLUE_GRAY
        # Enable UIManager when view is shown to catch window events
        self.ui.enable()

    def on_hide_view(self):
        # Disable UIManager when view gets inactive
        self.ui.disable()

    def on_draw(self):
        self.clear()
        self.ui.draw()


if __name__ == '__main__':
    window = arcade.Window(800, 600, "UIExample", resizable=True)
    window.show_view(MyView())
    window.run()