wxpython线程安全的方法

wx中实现了3个线程安全的函数。如果在线程中，直接访问并更新主线程的UI，会遇到问题，有时候阻塞UI或者更新不起作用，有时严重的话会引起python崩溃。

三个安全线程如下：

• wx.PostEvent
• wx.CallAfter
• wx.CallLater

其中，wx.CallLater是最抽象的线程安全函数，其次是callAfter，最后是PostEvent。

PostEvent用法：

import time
from threading import *
import wx

# Button definitions
ID_START = wx.NewId()
ID_STOP = wx.NewId()

# Define notification event for thread completion
EVT_RESULT_ID = wx.NewId()

def EVT_RESULT(win, func):
    """Define Result Event."""
    win.Connect(-1, -1, EVT_RESULT_ID, func)

class ResultEvent(wx.PyEvent):
    """Simple event to carry arbitrary result data."""
    def __init__(self, data):
        """Init Result Event."""
        wx.PyEvent.__init__(self)
        self.SetEventType(EVT_RESULT_ID)
        self.data = data

# Thread class that executes processing
class WorkerThread(Thread):
    """Worker Thread Class."""
    def __init__(self, notify_window):
        """Init Worker Thread Class."""
        Thread.__init__(self)
        self.setDaemon(1)
        self._notify_window = notify_window
        self._want_abort = 0
        # This starts the thread running on creation, but you could
        # also make the GUI thread responsible for calling this
        self.start()

    def run(self):
        """Run Worker Thread."""
        # This is the code executing in the new thread. Simulation of
        for i in range(10):
            time.sleep(1)
            if self._want_abort:
                # Use a result of None to acknowledge the abort (of
                # course you can use whatever you'd like or even
                # a separate event type)
                wx.PostEvent(self._notify_window, ResultEvent(None))
                return
            wx.PostEvent(self._notify_window, ResultEvent(i))
        # Here's where the result would be returned (this is an
        # example fixed result of the number 10, but it could be
        # any Python object)
        wx.PostEvent(self._notify_window, ResultEvent(10))

    def abort(self):
        """abort worker thread."""
        # Method for use by main thread to signal an abort
        self._want_abort = 1

# GUI Frame class that spins off the worker thread
class MainFrame(wx.Frame):
    """Class MainFrame."""
    def __init__(self, parent, id):
        """Create the MainFrame."""
        wx.Frame.__init__(self, parent, id, 'Thread Test')

        # Dumb sample frame with two buttons
        self.OkButton = wx.Button(self, ID_START, 'Start', pos=(0,0))
        wx.Button(self, ID_STOP, 'Stop', pos=(0,50))
        self.status = wx.StaticText(self, -1, '', pos=(0,100))

        self.Bind(wx.EVT_BUTTON, self.OnStart, id=ID_START)
        self.Bind(wx.EVT_BUTTON, self.OnStop, id=ID_STOP)

        # Set up event handler for any worker thread results
        EVT_RESULT(self,self.OnResult)

        # And indicate we don't have a worker thread yet
        self.worker = None

    def __Onfunc(self):
        import time
        time.sleep(10)

    def OnStart(self, event):
        """Start Computation."""
        # Trigger the worker thread unless it's already busy
        if not self.worker:
            self.status.SetLabel('Starting computation')
            self.worker = WorkerThread(self)

    def OnStop(self, event):
        """Stop Computation."""
        # Flag the worker thread to stop if running
        if self.worker:
            self.status.SetLabel('Trying to abort computation')
            self.worker.abort()

    def OnResult(self, event):
        """Show Result status."""

        # Process results here
        self.status.SetLabel('Computation Result: %s' % event.data)
        # In either event, the worker is done
        self.worker = None

class MainApp(wx.App):
    """Class Main App."""
    def OnInit(self):
        """Init Main App."""
        self.frame = MainFrame(None, -1)
        self.frame.Show(True)
        self.SetTopWindow(self.frame)
        return True

if __name__ == '__main__':
    app = MainApp(0)
    app.MainLoop()