python - Urwid 键盘触发弹出窗口

Question

当用户按下 H 键时，我试图在我的 urwid 应用程序顶部显示一个帮助对话框，但我似乎无法让它消失。它显示没有问题。我错过了什么？我一整天都在做这件事。

我看过几个描述不同实现方法的例子。我玩过信号，但无济于事。我不想使用可见的帮助按钮，而是完全依赖键盘快捷键。

import urwid

class Application(object):
    '''
    The console UI
    '''

    # The default color palette
    _palette = [
        ('banner', 'black', 'light gray'),
        ('selectable', 'white', 'black'),
        ('focus', 'black', 'light gray')
    ]

    def __init__(self):
        self._content = [
            urwid.Text('Initializing...', align = 'left')
        ]

        # Body
        self._body_walker = urwid.SimpleListWalker(self._content)
        self._body_list = urwid.ListBox(self._body_walker)
        self._body_padding = urwid.Padding(
            self._body_list,
            left = 1,
            right = 1
        )
        self._body = urwid.LineBox(self._body_padding)

        # Loop
        self._loop = urwid.MainLoop(
            self._body,
            self._palette,
            unhandled_input = self._handle_input
        )

    def reset_layout(self):
        '''
        Resets the console UI to the default layout
        '''

        self._loop.widget = self._body
        self._loop.draw_screen()

    def _handle_input(self, key):
        '''
        Handles user input to the console UI

        Args:
            key (object): A mouse or keyboard input sequence
        '''

        if type(key) == str:
            if key in ('q', 'Q'):
                raise urwid.ExitMainLoop()
            elif key in ('h', 'H'):
                self.dialog(
                    [
                        'Urwid v1.3.1\n',
                        '\n',
                        'Press Q to quit\n',
                        'Press H for help'
                    ]
                )
        elif type(key) == tuple:
            pass

    def print(self, string = '', align = 'left'):
        '''
        Prints a string to the console UI

        Args:
            string (str): The string to print
            align (str): The alignment of the printed text
        '''

        self._body_walker.append(
            urwid.Text(string, align = align)
        )

    def printf(self, *strings):
        '''
        Prints multiple strings with different alignment

        Args:
            strings (tuple): A string, alignment pair
        '''

        self._body_walker.append(
            urwid.Columns(
                [
                    urwid.Text(string, align = align)
                    for string, align in strings
                ]
            )
        )

    def start(self):
        '''
        Starts the console UI
        '''

        self._loop.run()

    def dialog(self, text = ['']):
        '''
        Overlays a dialog box on top of the console UI

        Args:
            test (list): A list of strings to display
        '''

        # Header
        header_text = urwid.Text(('banner', 'Help'), align = 'center')
        header = urwid.AttrMap(header_text, 'banner')

        # Body
        body_text = urwid.Text(text, align = 'center')
        body_filler = urwid.Filler(body_text, valign = 'top')
        body_padding = urwid.Padding(
            body_filler,
            left = 1,
            right = 1
        )
        body = urwid.LineBox(body_padding)

        # Footer
        footer = urwid.Button('Okay', self.reset_layout())
        footer = urwid.AttrWrap(footer, 'selectable', 'focus')
        footer = urwid.GridFlow([footer], 8, 1, 1, 'center')

        # Layout
        layout = urwid.Frame(
            body,
            header = header,
            footer = footer,
            focus_part = 'footer'
        )

        w = urwid.Overlay(
            urwid.LineBox(layout),
            self._body,
            align = 'center',
            width = 40,
            valign = 'middle',
            height = 10
        )

        self._loop.widget = w

Application().start()

Answer 1

你能想象在意识到我需要做的就是在按钮的回调中去掉括号后我现在有多愚蠢吗？

footer = urwid.Button('Okay', self.reset_layout)

这里有一些示例代码，供将来偶然发现此问题的人使用。

import urwid

class Application(object):
    '''
    The console UI
    '''

    # The default color palette
    _palette = [
        ('banner', 'black', 'light gray'),
        ('selectable', 'white', 'black'),
        ('focus', 'black', 'light gray')
    ]

    def __init__(self):
        self._body = urwid.SolidFill('.')
        self._pile = urwid.Pile(
            [
                self.dialog()
            ]
        )
        self._over = urwid.Overlay(
            self._pile,
            self._body,
            align = 'center',
            valign = 'middle',
            width = 20,
            height = 10
        )

        # Loop
        self._loop = urwid.MainLoop(
            self._over,
            self._palette,
            unhandled_input = self._handle_input
        )

    def _handle_input(self, key):
        '''
        Handles user input to the console UI

        Args:
            key (object): A mouse or keyboard input sequence
        '''

        if type(key) == str:
            if key in ('q', 'Q'):
                raise urwid.ExitMainLoop()
        elif type(key) == tuple:
            pass

    def start(self):
        '''
        Starts the console UI
        '''

        self._loop.run()

    def do(self, thing):
        self._loop.widget = self._body
        #self._pile.contents.clear()

    def dialog(self):
        '''
        Overlays a dialog box on top of the console UI
        '''

        # Header
        header_text = urwid.Text(('banner', 'Help'), align = 'center')
        header = urwid.AttrMap(header_text, 'banner')

        # Body
        body_text = urwid.Text('Hello world', align = 'center')
        body_filler = urwid.Filler(body_text, valign = 'top')
        body_padding = urwid.Padding(
            body_filler,
            left = 1,
            right = 1
        )
        body = urwid.LineBox(body_padding)

        # Footer
        footer = urwid.Button('Okay', self.do)
        footer = urwid.AttrWrap(footer, 'selectable', 'focus')
        footer = urwid.GridFlow([footer], 8, 1, 1, 'center')

        # Layout
        layout = urwid.Frame(
            body,
            header = header,
            footer = footer,
            focus_part = 'footer'
        )

        return layout

Application().start()