使用tkinter在GUI上显示程序的输出?

时间:2018-02-25 19:23:19

标签: python user-interface tkinter output

我想在GUI上显示我的程序的“实时”输出(打印在其中的所有内容)。我怎样才能访问我的输出?以及在文本框中显示它的正确方法是什么?

编辑:我哪里错了? (我希望“hello world”出现在文本框内。(Test2是正在运行的程序))

from tkinter import *
from subprocess import *

print("Hello world")

def func():
    proc = Popen("Test2.py", stdout=PIPE, shell=True)
    proc = proc.communicate()
    output.insert(END, proc)

Master = Tk()
Check = Button(Master, text="Display output", command=func)
Quit = Button(Master, text="Exit", fg="red", command=Master.quit)
output = Text(Master, width=40, height=8)

Check.pack(padx=20, pady=8)
Quit.pack(padx=20, pady=18)
output.pack()

Master.mainloop()

1 个答案:

答案 0 :(得分:1)

我花了时间在another question的答案中调试和修改errorwindow.py模块,因此它可以在Python 2 3中工作 - 链接中的代码答案是为Python 2.x编写的。注意我只做了使它在两个版本下运行所需的最低要求。脚本的修改版本已命名为errorwindow3k.py(尽管它在Python 2中也可以使用)。

大多数问题仅仅是由于模块重命名,但是有一个更难以弄清楚,结果是由于切换到Unicode字符串是版本3中的默认字符串类型 - 显然(在Windows无论如何),进程之间的管道是字节流,而不是Unicode字符。幸运的是,在另一方面解码然后编码数据的“修复”在Python 2中也没有受到影响,这使得纠正问题变得相当容易。

这个好处是使用它非常容易。只需import它就可以从发送到sys.stderrsys.stdout的任何输出的那一点开始,以便在显示信息时根据需要显示基于tkinter的输出窗口。在示例代码中,只需在import errorwindow3k之前的某处插入print("Hello world")

文件 errorwindow3k.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
#
#  See the comments and doc string below.
#
#   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.
#
#               Recently updated it to work in both Python 2 and Python 3.

"""
    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
try:
    import thread
except ModuleNotFoundError:  # Python 3
    import _thread as thread
import os

EXC_INFO_FILENAME = 'exc_info.txt'

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
    try:
        from Tkinter import BOTH, END, Frame, Text, TOP, YES
        import tkFont
        import Queue
    except ModuleNotFoundError:  # Python 3
        from tkinter import BOTH, END, Frame, Text, TOP, YES
        import tkinter.font as tkFont
        import queue as Queue

    Q_EMPTY = Queue.Empty  # An exception class.
    queue = Queue.Queue(1000)  # FIFO

    def read_stdin(app, bufsize=4096):
        fd = sys.stdin.fileno()  # File descriptor for os.read() calls.
        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)
            # Create title based on the arguments passed to the spawned script:
            #   argv[0]: name of this script (ignored)
            #   argv[1]: name of script that imported this module
            #   argv[2]: name of redirected stream (optional)
            if len(sys.argv) < 2:
                title = "Output stream from unknown source"
            elif len(sys.argv) < 3:
                title = "Output stream from %s" % (sys.argv[1],)
            else:  # Assume it's a least 3.
                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 text copying 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, ())  # Start polling 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().decode()  # Must decode for Python 3.
                    if not data:
                        data = '[EOF]'
                        go = False
                    log_insert(END, data)
                    log_see(END)
                except Q_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 flush(self):  # NO-OP.
            pass

        def __getattr__(self, attr):
            if attr == 'pipe':  # Attribute doesn't exist, so create it.
                # Launch this module as a separate process to display any output
                # it receives.
                # Note: It's important to put double quotes around everything just in
                # case any have embedded space characters.
                command = '"%s" "%s" "%s" "%s"' % (sys.executable,                # executable
                                                   __file__,                      # argv[0]
                                                   os.path.basename(sys.argv[0]), # argv[1]
                                                   self.name)                     # argv[2]
                #
                # Typical command and arg values on receiving end:
                #   C:\Python3\python[w].exe                                      # executable
                #   C:\vols\Files\PythonLib\Stack Overflow\errorwindow3k.py       # argv[0]
                #   errorwindow3k_test.py                                         # argv[1]
                #   stderr                                                        # argv[2]

                # Execute this script directly as __main__ with a stdin PIPE for sending
                # output to it.
                try:
                    # Had to also make stdout and stderr PIPEs too, to 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_FILENAME, 'wt') as info:
                        info.write('fatal error occurred spawning output process')
                        info.write('exeception info:' + msg)
                        traceback.print_exc(file=info)

                    sys.exit('fatal error occurred')

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

        def write(self, data):
            with self.lock:
                data = data.encode()  # Must encode for Python 3.
                self.pipe.write(data)  # First reference to pipe attr will cause an
                                       # OutputPipe process for the stream to be created.

    # Clean-up any left-over debugging files.
    try:
        os.remove(DEBUG_FILENAME)  # Delete previous file, if any.
    except Exception:
        pass
    try:
        os.remove(EXC_INFO_FILENAME)  # Delete previous file, if any.
    except Exception:
        pass

    # Redirect standard output streams in the process that imported this module.
    sys.stderr = OutputPipe('stderr')
    sys.stdout = OutputPipe('stdout')

如果您对其工作方式有任何疑问,请随时在评论中提问。