python - 当函数运行时写入 easygui 文本框？

Question

我当前正在使用 easygui 运行脚本来接收用户输入。在命令行中运行的旧脚本只会在命令行中打印用户需要知道的任何内容，但我已将其更改为在需要输入时在新的 easygui 框中输出通知。

我想要做的是获得进度，正在运行的函数内的每个操作在完成时打印到文本框中。在命令行中，我可以使用 print "text" 但我无法让它在 easygui 中实时发生。目前，我正在附加一个列表，因此我有一个文本框，可以在一切完成后显示该函数的结果，但我希望在注释过程完成时弹出大文本框窗口并打印该行。这可行吗？

以下是我附加列表的方式:

result_list = []
record_str = "\n Polling has completed for 502."
result_list.append(record_str)
eg.textbox("Polling Status", "Daily polling completion status:", result_list)

Answer 1

我认为除了修改模块之外，没有任何简单的方法可以让 EasyGUI 的 textbox 函数执行您想要的操作。由于它是一个函数而不是一个类，因此您甚至无法从它派生子类以轻松重用其代码。

但是，创建一个单独的 Tkinter 窗口是完全可行的，该窗口仅显示发送到它的文本行，使用我在 comp.lang.python 上的线程中发现的一些代码的增强版本。新闻组。

原始代码旨在仅捕获并显示 GUI 应用程序的 stderr 输出，该应用程序通常没有 stderr 输出句柄，因此该模块被命名为 错误窗口。然而，我修改了它，以便能够在我开发的一个基于 easygui 的应用程序中将 stderr 和 stdout 重定向到此类窗口，但我从未解决过重命名它或更新其中的注释以提及 stdout 重定向。 ;-)

无论如何，该模块的工作原理是在导入时定义并创建名为 OutputPipe 的类文件类的两个实例，并将它们分配给 sys.path 。 stdout 和 sys.stderr I/O 流文件对象，在 Python .pyw GUI 应用程序(在 Windows 上)中通常为 None )。当输出第一次发送到其中任何一个时，同一个模块将作为单独的 Python 进程启动，并带有其 stdin、stdout 和 stderr I/O 处理与原始进程的管道连接。

发生了很多事情，但如果没有别的事，稍微研究一下可能会给您一些关于如何让 easygui 的 textbox 执行任务的想法你要。希望这会有所帮助。

注意:发布的代码适用于 Python 2.x，my answer 中有一个可在 Python 2 和 3 中运行的修改版本。如果有人感兴趣的话，再回答另一个问题。

文件errorwindow.py:

# Code derived from Bryan Olson's source posted in this related Usenet discussion:
#   https://groups.google.com/d/msg/comp.lang.python/HWPhLhXKUos/TpFeWxEE9nsJ
#   https://groups.google.com/d/msg/comp.lang.python/HWPhLhXKUos/eEHYAl4dH9YJ
#
#   Here's a module to show stderr output from console-less Python
#   apps, and stay out of the way otherwise. I plan to make a ASPN
#   recipe of it, but I thought I'd run it by this group first.
#
#   To use it, import the module. That's it. Upon import it will
#   assign sys.stderr.
#
#   In the normal case, your code is perfect so nothing ever gets
#   written to stderr, and the module won't do much of anything.
#   Upon the first write to stderr, if any, the module will launch a
#   new process, and that process will show the stderr output in a
#   window. The window will live until dismissed; I hate, hate, hate
#   those vanishing-consoles-with-critical-information.
#
#   The code shows some arguably-cool tricks. To fit everthing in
#   one file, the module runs the Python interpreter on itself; it
#   uses the "if __name__ == '__main__'" idiom to behave radically
#   differently upon import versus direct execution. It uses TkInter
#   for the window, but that's in a new process; it does not import
#   TkInter into your application.
#
#   To try it out, save it to a file -- I call it "errorwindow.py" -
#   - and import it into some subsequently-incorrect code. For
#   example:
#
#        import errorwindow
#
#        a = 3 + 1 + nonesuchdefined
#
#   should cause a window to appear, showing the traceback of a
#   Python NameError.
#
#   --
#   --Bryan
#   ----------------------------------------------------------------
#
#   martineau - Modified to use subprocess.Popen instead of the os.popen
#               which has been deprecated since Py 2.6. Changed so it
#               redirects both stdout and stderr. Added numerous
#               comments, and also inserted double quotes around paths
#               in case they have embedded space characters in them, as
#               they did on my Windows system.

"""
    Import this module into graphical Python apps to provide a
    sys.stderr. No functions to call, just import it. It uses
    only facilities in the Python standard distribution.

    If nothing is ever written to stderr, then the module just
    sits there and stays out of your face. Upon write to stderr,
    it launches a new process, piping it error stream. The new
    process throws up a window showing the error messages.
"""
import subprocess
import sys
import thread
import os

if __name__ == '__main__':  # when spawned as separate process
    # create window in which to display output
    # then copy stdin to the window until EOF
    # will happen when output is sent to each OutputPipe created
    from Tkinter import BOTH, END, Frame, Text, TOP, YES
    import tkFont
    import Queue

    queue = Queue.Queue(100)

    def read_stdin(app, bufsize=4096):
        fd = sys.stdin.fileno()  # gets file descriptor
        read = os.read
        put = queue.put
        while True:
            put(read(fd, bufsize))

    class Application(Frame):
        def __init__(self, master=None, font_size=8, text_color='#0000AA', rows=25, cols=100):
            Frame.__init__(self, master)
            # argv[0]: name of this script (not used)
            # argv[1]: name of script that imported this module
            # argv[2]: name of redirected stream (optional)
            if len(sys.argv) < 3:
                title = "Output Stream from %s" % (sys.argv[1],)
            else:
                title = "Output Stream '%s' from %s" % (sys.argv[2], sys.argv[1])
            self.master.title(title)
            self.pack(fill=BOTH, expand=YES)
            font = tkFont.Font(family='Courier', size=font_size)
            width = font.measure(' '*(cols+1))
            height = font.metrics('linespace')*(rows+1)
            self.configure(width=width, height=height)
            self.pack_propagate(0)  # force frame to be configured size
            self.logwidget = Text(self, font=font)
            self.logwidget.pack(side=TOP, fill=BOTH, expand=YES)
            # Disallow key entry, but allow copy with <Control-c>
            self.logwidget.bind('<Key>', lambda x: 'break')
            self.logwidget.bind('<Control-c>', lambda x: None)
            self.logwidget.configure(foreground=text_color)
            #self.logwidget.insert(END, '==== Start of Output Stream ====\n\n')
            #self.logwidget.see(END)
            self.after(200, self.start_thread, ())

        def start_thread(self, _):
            thread.start_new_thread(read_stdin, (self,))
            self.after(200, self.check_q, ())

        def check_q(self, _):
            log = self.logwidget
            log_insert = log.insert
            log_see = log.see
            queue_get_nowait = queue.get_nowait
            go = True
            while go:
                try:
                    data = queue_get_nowait()
                    if not data:
                        data = '[EOF]'
                        go = False
                    log_insert(END, data)
                    log_see(END)
                except Queue.Empty:
                    self.after(200, self.check_q, ())
                    go = False

    app = Application()
    app.mainloop()

else: # when module is first imported
    import traceback
    class OutputPipe(object):
        def __init__(self, name=''):
            self.lock = thread.allocate_lock()
            self.name = name

        def __getattr__(self, attr):
            if attr == 'pipe':  # pipe attribute hasn't been created yet
                # launch this module as a separate process to display any output
                # it receives.
                # Note: It's important to put double quotes around everything in case
                # they have embedded space characters.
                command = '"%s" "%s" "%s" "%s"' % (sys.executable,                # command
                                                   __file__,                      # argv[0]
                                                   os.path.basename(sys.argv[0]), # argv[1]
                                                   self.name)                     # argv[2]

                # sample command and arg values on receiving end:
                #   E:\Program Files\Python\python[w].exe                         # command
                #   H:\PythonLib\TestScripts\PyRemindWrk\errorwindow.py           # argv[0]
                #   errorwindow.py                                                # argv[1]
                #   stderr                                                        # argv[2]

                # execute this script as __main__ with a stdin PIPE for sending output to it
                try:
                    # had to make stdout and stderr PIPEs too, to make it work with pythonw.exe
                    self.pipe = subprocess.Popen(command, bufsize=0,
                                                 stdin=subprocess.PIPE,
                                                 stdout=subprocess.PIPE,
                                                 stderr=subprocess.PIPE).stdin
                except Exception:
                    # output exception info to a file since this module isn't working
                    exc_type, exc_value, exc_traceback = sys.exc_info()
                    msg = ('%r exception in %s\n' %
                            (exc_type.__name__, os.path.basename(__file__)))
                    with open('exc_info.txt', 'wt') as info:
                        info.write('msg:' + msg)
                        traceback.print_exc(file=info)
                    sys.exit('fatal error occurred spawning output process')

            return super(OutputPipe, self).__getattribute__(attr)

        def write(self, data):
            with self.lock:
                self.pipe.write(data)  # 1st reference to pipe attr will cause it to be created

    # redirect standard output streams in the process importing the module
    sys.stderr = OutputPipe('stderr')
    sys.stdout = OutputPipe('stdout')