wxpython threading display images as they are loaded - multithreading

I am writing a GUI to display a few images (book covers from amazon) from a defined list of URLs, I have been able to load them in a panel successfully, but in spite of using threads, the GUI seems to wait till all the loop is over and then all the images show up at once, how can I achieve the GUI to display each images as they are fetched run time..the GUI is basically frozen till the images are fetched...Thanks!
the question again is to ensure I get to display each image on the GUI as they are pulled and not all at once...
import wx
import os
import sys
import urllib2
import cStringIO
import threading
import time
urls = ['https://images-na.ssl-images-amazon.com/images/I/51-u3J3mtTL._AC_US100_.jpg',
'https://images-na.ssl-images-amazon.com/images/I/51cRqX8DTgL._AC_US100_.jpg',
'https://images-na.ssl-images-amazon.com/images/I/515iBchIIzL._AC_US100_.jpg',
'https://images-na.ssl-images-amazon.com/images/I/511MaP7GeJL._AC_US100_.jpg',
'https://images-na.ssl-images-amazon.com/images/I/51jizRmRYYL._AC_US160_.jpg',
'https://images-na.ssl-images-amazon.com/images/I/51jizRmRYYL._AC_US160_.jpg',
'https://images-na.ssl-images-amazon.com/images/I/31Pw7voGDFL._AC_US160_.jpg',
'https://images-na.ssl-images-amazon.com/images/I/51g30m1xpPL._AC_US160_.jpg',
'https://images-na.ssl-images-amazon.com/images/I/51qx+6aQUnL._AC_US160_.jpg']
class Example(wx.Frame):
def __init__(self, *args, **kwargs):
super(Example, self).__init__(*args, **kwargs)
self.InitUI()
self.Ctrls()
self.makeButtons()
def makeButtons(self):
def _update_data(data):
time.sleep(2)
stream = cStringIO.StringIO(data)
bmp = wx.BitmapFromImage( wx.ImageFromStream( stream ) )
button = wx.Button(self.panel, -1, "Book cover", style=wx.ALIGN_CENTER, size=wx.Size(100,100))
button.SetToolTipString("wx.Button can how have an icon on the left, right,\n"
"above or below the label.")
button.SetBitmap(bmp,
wx.LEFT # Left is the default, the image can be on the other sides too
#wx.RIGHT
#wx.TOP
#wx.BOTTOM
)
button.SetBitmapMargins((4,4))
button.SetFont(wx.Font(8, wx.SWISS, wx.NORMAL, wx.BOLD, False))
self.wrapSizer.Add(button, 1, wx.EXPAND)
self.Show(True)
self.panel.Layout()
def f():
f = urllib2.urlopen(url)
data = f.read()
wx.CallAfter(_update_data, data)
for url in urls:
threading.Thread(target=f).start()
def InitUI(self):
self.SetSize((800, 400))
self.SetTitle('Dynamically Flow Buttons to Next Row on Window-Resize')
self.Centre()
def Sizers(self):
self.wrapSizer = wx.WrapSizer()
self.panel.SetSizer(self.wrapSizer)
def Ctrls(self):
self.panel = wx.Panel(parent=self,pos=wx.Point(0,0), size=wx.Size(750,550), style=wx.TAB_TRAVERSAL)
self.Sizers()
def main():
ex = wx.App()
Example(None)
ex.MainLoop()
if __name__ == '__main__':
main()

It would also be possible to spin off all threads at once, as has been tried in the code sample in the question. The problem in the original code was that the GUI was blocking due to the time delay in processing the request for the bitmaps.
Bear in mind that in the sample below the order of the bitmaps will depend on the order the threads are finishing (which is random in this case).
import wx
import urllib2
import cStringIO
import threading
import time
from random import random
urls = ['https://images-na.ssl-images-amazon.com/images/I/51-u3J3mtTL._AC_US100_.jpg',
'https://images-na.ssl-images-amazon.com/images/I/51cRqX8DTgL._AC_US100_.jpg',
'https://images-na.ssl-images-amazon.com/images/I/515iBchIIzL._AC_US100_.jpg',
'https://images-na.ssl-images-amazon.com/images/I/511MaP7GeJL._AC_US100_.jpg',
'https://images-na.ssl-images-amazon.com/images/I/51jizRmRYYL._AC_US160_.jpg',
'https://images-na.ssl-images-amazon.com/images/I/51jizRmRYYL._AC_US160_.jpg',
'https://images-na.ssl-images-amazon.com/images/I/31Pw7voGDFL._AC_US160_.jpg',
'https://images-na.ssl-images-amazon.com/images/I/51g30m1xpPL._AC_US160_.jpg',
'https://images-na.ssl-images-amazon.com/images/I/51qx+6aQUnL._AC_US160_.jpg']
def url2bmp(url, callback):
f = urllib2.urlopen(url)
data = f.read()
# to simulate random read delay
time.sleep(2 * random())
stream = cStringIO.StringIO(data)
bmp = wx.BitmapFromImage(wx.ImageFromStream(stream))
wx.CallAfter(callback, bmp)
class Example(wx.Frame):
def __init__(self, *args, **kwargs):
super(Example, self).__init__(*args, **kwargs)
self.InitUI()
self.Ctrls()
self.Show(True)
self.makeButtons()
def makeButtons(self):
for url in urls:
threading.Thread(target=url2bmp, args=(url, self.update_ui)).start()
def update_ui(self, bmp):
button = wx.Button(self.panel, -1, "Book cover", style=wx.ALIGN_CENTER, size=wx.Size(100,100))
button.SetToolTipString("wx.Button can how have an icon on the left, right,\n"
"above or below the label.")
button.SetBitmap(bmp,
wx.LEFT # Left is the default, the image can be on the other sides too
#wx.RIGHT
#wx.TOP
#wx.BOTTOM
)
self.wrapSizer.Add(button, 1, wx.EXPAND)
self.panel.Layout()
def InitUI(self):
self.SetSize((800, 400))
self.SetTitle('Dynamically Flow Buttons to Next Row on Window-Resize')
self.Centre()
def Sizers(self):
self.wrapSizer = wx.WrapSizer()
self.panel.SetSizer(self.wrapSizer)
def Ctrls(self):
self.panel = wx.Panel(parent=self,pos=wx.Point(0,0), size=wx.Size(750,550), style=wx.TAB_TRAVERSAL)
self.Sizers()
def main():
ex = wx.App()
Example(None)
ex.MainLoop()
if __name__ == '__main__':
main()
EDIT: Rewrote the example to generate the empty buttons first, then apply the bitmap as soon as they arrive. This is uglier now and it would be time to refactor to have a more safe mapping button to url than (mis)using the label.
import wx
import urllib2
import cStringIO
import threading
import time
from random import random
urls = ['https://images-na.ssl-images-amazon.com/images/I/51-u3J3mtTL._AC_US100_.jpg',
'https://images-na.ssl-images-amazon.com/images/I/51cRqX8DTgL._AC_US100_.jpg',
'https://images-na.ssl-images-amazon.com/images/I/515iBchIIzL._AC_US100_.jpg',
'https://images-na.ssl-images-amazon.com/images/I/511MaP7GeJL._AC_US100_.jpg',
'https://images-na.ssl-images-amazon.com/images/I/51jizRmRYYL._AC_US160_.jpg',
'https://images-na.ssl-images-amazon.com/images/I/51jizRmRYYL._AC_US160_.jpg',
'https://images-na.ssl-images-amazon.com/images/I/31Pw7voGDFL._AC_US160_.jpg',
'https://images-na.ssl-images-amazon.com/images/I/51g30m1xpPL._AC_US160_.jpg',
'https://images-na.ssl-images-amazon.com/images/I/51qx+6aQUnL._AC_US160_.jpg']
def url2bmp(url, callback):
f = urllib2.urlopen(url)
data = f.read()
# to simulate random read delay
time.sleep(2 * random())
stream = cStringIO.StringIO(data)
bmp = wx.BitmapFromImage(wx.ImageFromStream(stream))
wx.CallAfter(callback, url, bmp)
class Example(wx.Frame):
def __init__(self, *args, **kwargs):
super(Example, self).__init__(*args, **kwargs)
self.InitUI()
self.Ctrls()
self.Show(True)
self.makeButtons()
def makeButtons(self):
for url in urls:
self.update_ui(url)
threading.Thread(target=url2bmp, args=(url, self.update_ui)).start()
def update_ui(self, url, bmp=None):
if bmp is None:
# create button, but not bitmap
button = wx.Button(self.panel, -1, url, style=wx.ALIGN_CENTER, size=wx.Size(100,100))
button.SetToolTipString("wx.Button can how have an icon on the left, right,\n"
"above or below the label.")
self.wrapSizer.Add(button, 1, wx.EXPAND)
else:
children = self.wrapSizer.GetChildren()
# http://www.blog.pythonlibrary.org/2012/08/24/wxpython-how-to-get-children-widgets-from-a-sizer/
for widget in children:
button = widget.GetWindow()
if isinstance(button, wx.Button):
if button.GetLabel() == url:
button.SetBitmap(bmp,
wx.LEFT # Left is the default, the image can be on the other sides too
#wx.RIGHT
#wx.TOP
#wx.BOTTOM
)
button.SetLabel('')
self.panel.Layout()
def InitUI(self):
self.SetSize((800, 400))
self.SetTitle('Dynamically Flow Buttons to Next Row on Window-Resize')
self.Centre()
def Sizers(self):
self.wrapSizer = wx.WrapSizer()
self.panel.SetSizer(self.wrapSizer)
def Ctrls(self):
self.panel = wx.Panel(parent=self,pos=wx.Point(0,0), size=wx.Size(750,550), style=wx.TAB_TRAVERSAL)
self.Sizers()
def main():
ex = wx.App()
Example(None)
ex.MainLoop()
if __name__ == '__main__':
main()

Have allowed myself to rewrite. Important is to get out of the __init__ method as soon as possible (calling Show before starting the thread) and letting the thread working asynchronuosly. You also started all your threads at once, while this example uses one thread to get one bitmap after the other.
import wx
import os
import sys
import urllib2
import cStringIO
import threading
import time
urls = ['https://images-na.ssl-images-amazon.com/images/I/51-u3J3mtTL._AC_US100_.jpg',
'https://images-na.ssl-images-amazon.com/images/I/51cRqX8DTgL._AC_US100_.jpg',
'https://images-na.ssl-images-amazon.com/images/I/515iBchIIzL._AC_US100_.jpg',
'https://images-na.ssl-images-amazon.com/images/I/511MaP7GeJL._AC_US100_.jpg',
'https://images-na.ssl-images-amazon.com/images/I/51jizRmRYYL._AC_US160_.jpg',
'https://images-na.ssl-images-amazon.com/images/I/51jizRmRYYL._AC_US160_.jpg',
'https://images-na.ssl-images-amazon.com/images/I/31Pw7voGDFL._AC_US160_.jpg',
'https://images-na.ssl-images-amazon.com/images/I/51g30m1xpPL._AC_US160_.jpg',
'https://images-na.ssl-images-amazon.com/images/I/51qx+6aQUnL._AC_US160_.jpg']
def gen_urls():
"""Gives back one bitmap after another."""
for url in urls:
f = urllib2.urlopen(url)
data = f.read()
time.sleep(2)
stream = cStringIO.StringIO(data)
bmp = wx.BitmapFromImage( wx.ImageFromStream( stream ) )
yield bmp
class Example(wx.Frame):
def __init__(self, *args, **kwargs):
super(Example, self).__init__(*args, **kwargs)
self.InitUI()
self.Ctrls()
self.Show(True)
threading.Thread(target=self.makeButtons).start()
def makeButtons(self):
for bmp in gen_urls():
wx.CallAfter(self.update_ui, bmp)
def update_ui(self, bmp):
button = wx.Button(self.panel, -1, "Book cover", style=wx.ALIGN_CENTER, size=wx.Size(100,100))
button.SetToolTipString("wx.Button can how have an icon on the left, right,\n"
"above or below the label.")
button.SetBitmap(bmp,
wx.LEFT # Left is the default, the image can be on the other sides too
#wx.RIGHT
#wx.TOP
#wx.BOTTOM
)
button.SetBitmapMargins((4,4))
button.SetFont(wx.Font(8, wx.SWISS, wx.NORMAL, wx.BOLD, False))
self.wrapSizer.Add(button, 1, wx.EXPAND)
self.panel.Layout()
def InitUI(self):
self.SetSize((800, 400))
self.SetTitle('Dynamically Flow Buttons to Next Row on Window-Resize')
self.Centre()
def Sizers(self):
self.wrapSizer = wx.WrapSizer()
self.panel.SetSizer(self.wrapSizer)
def Ctrls(self):
self.panel = wx.Panel(parent=self,pos=wx.Point(0,0), size=wx.Size(750,550), style=wx.TAB_TRAVERSAL)
self.Sizers()
def main():
ex = wx.App()
Example(None)
ex.MainLoop()
if __name__ == '__main__':
main()

Related

Connecting external threaded log to PyQt5 QPlainTextEdit

I'm new to PyQt and handlers in general, I tried to read from every repo I found but I can't figure out how to fix my issue, as you can see in my code, I'm executing logging thread in the background and I'm trying to show the logs in my QPlainTextEdit console - for some reason I can see the logs in my terminal and the text_box doesn't get the logs at all,
I will appreciate a lot your smart help.
import pandas as pd
from PyQt5.QtWidgets import *
from PyQt5.QtCore import *
from PyQt5.QtGui import *
import time
import os
import threading
import json
class ConsolePanelHandler(logging.Handler):
def __init__(self, stream):
# super().__init__()
logging.Handler.__init__(self)
# logging.StreamHandler.__init__(self, stream)
self.stream = stream
def handle(self, record):
rv = self.filter(record)
if rv:
self.acquire()
try:
self.emit(record)
finally:
self.release()
return rv
def emit(self, record):
try:
stream = self.stream
stream(self.format(record))
except RecursionError:
raise
except Exception:
self.handleError(self.format(record))
def thread():
for index in range(20):
logging.warning('scheiBe '+str(index))
time.sleep(1)
class MainWindow(QMainWindow):
def __init__(self):
super().__init__()
layout = QVBoxLayout()
self.continue_ = QPushButton("Continue")
self.continue_.setStyleSheet("background-color: green")
self.continue_.setFont(QFont('SansSerif', 10))
self.continue_.setFixedSize(QSize(300, 22))
self.pause = QPushButton("Pause")
self.pause.setStyleSheet("background-color: orange")
self.pause.setFont(QFont('SansSerif', 10))
self.pause.setFixedSize(QSize(300, 22))
self.stop = QPushButton("Stop")
self.stop.setStyleSheet("background-color: #FD4B4B")
self.stop.setFont(QFont('SansSerif', 10))
self.stop.setFixedSize(QSize(300, 22))
self.text_box = QPlainTextEdit()
self.text_box.setPlaceholderText("Bugs will be printed here")
self.text_box.setReadOnly(True)
logging.getLogger().addHandler(self.text_box)
logging.getLogger().setLevel(logging.DEBUG)
ConsolePanelHandler(self.appendDebug , logging.DEBUG)
self.text_box.moveCursor(QTextCursor.End)
layout.addWidget(self.continue_)
layout.addWidget(self.pause)
layout.addWidget(self.stop)
layout.addWidget(self.text_box)
self.w = QWidget()
self.w.setLayout(layout)
self.setCentralWidget(self.w)
thread1 = threading.Thread(target=thread, args=(), daemon=True)
thread1.start()
self.show()
def closeEvent(self, event):
close = QMessageBox()
close.setText("Are you sure want to stop and exit?")
close.setStandardButtons(QMessageBox.Yes | QMessageBox.Cancel)
close = close.exec()
if close == QMessageBox.Yes:
sys.exit()
else:
event.ignore()
def appendDebug(self, string):
self.text_box.appendPlainText(string +'\n')
if __name__ == "__main__":
app = QApplication([])
window = MainWindow()
sys.exit(app.exec())
First, you should not pass the function that updates the text_area instead you should create a pyqtSignal which updates the text_area and pass it to ConsolePanelHandler.
Add ConsolePanelHandler as handler not text_area to logging.getLogger().addHandler()
and it is recommended to use QThread instead of threading.Thread
here is the complete updated code.
# import pandas as pd
from PyQt5.QtWidgets import *
from PyQt5.QtCore import *
from PyQt5.QtGui import *
import time
import os
import sys
import threading
import json
import logging
class ConsolePanelHandler(logging.Handler):
def __init__(self, sig):
# super().__init__()
logging.Handler.__init__(self)
# logging.StreamHandler.__init__(self, stream)
self.stream = sig
def handle(self, record):
rv = self.filter(record)
if rv:
self.acquire()
try:
self.emit(record)
finally:
self.release()
return rv
def emit(self, record):
try:
self.stream.emit(self.format(record))
except RecursionError:
raise
except Exception:
self.handleError(record)
class thread(QThread):
def run(self) -> None:
for index in range(20):
logging.warning('scheiBe ' + str(index))
self.sleep(1)
class MainWindow(QMainWindow):
sig = pyqtSignal(str)
def __init__(self):
super().__init__()
self.layout = QVBoxLayout()
self.continue_ = QPushButton("Continue")
self.continue_.setStyleSheet("background-color: green")
self.continue_.setFont(QFont('SansSerif', 10))
self.continue_.setFixedSize(QSize(300, 22))
self.pause = QPushButton("Pause")
self.pause.setStyleSheet("background-color: orange")
self.pause.setFont(QFont('SansSerif', 10))
self.pause.setFixedSize(QSize(300, 22))
self.stop = QPushButton("Stop")
self.stop.setStyleSheet("background-color: #FD4B4B")
self.stop.setFont(QFont('SansSerif', 10))
self.stop.setFixedSize(QSize(300, 22))
self.c = ConsolePanelHandler(self.sig)
self.text_box = QPlainTextEdit()
self.text_box.setPlaceholderText("Bugs will be printed here")
self.text_box.setReadOnly(True)
logging.getLogger().addHandler(self.c)
logging.getLogger().setLevel(logging.DEBUG)
self.sig.connect(self.appendDebug)
self.text_box.moveCursor(QTextCursor.End)
self.layout.addWidget(self.continue_)
self.layout.addWidget(self.pause)
self.layout.addWidget(self.stop)
self.layout.addWidget(self.text_box)
self.w = QWidget()
self.w.setLayout(self.layout)
self.setCentralWidget(self.w)
self.thread1 = thread(self) # self is parent for Qthread so Qthread will be destroyed when it's parent no longer exist
self.thread1.start()
self.show()
def closeEvent(self, event):
close = QMessageBox()
close.setText("Are you sure want to stop and exit?")
close.setStandardButtons(QMessageBox.Yes | QMessageBox.Cancel)
close = close.exec()
if close == QMessageBox.Yes:
self.thread1.terminate()
sys.exit()
else:
event.ignore()
#pyqtSlot(str)
def appendDebug(self, string):
self.text_box.appendPlainText(string + '\n')
if __name__ == "__main__":
app = QApplication([])
window = MainWindow()
sys.exit(app.exec())

Open another wx.python frame cause the main UI to be blocked

I am trying to open another wx frame from a main frame UI. I followed the example shown here: https://wiki.wxpython.org/CallAfter but my main UI is still blocked.
Here is the event listener on the main UI:
def testShowGUI(self):
# This process is a long one
# It uses the vtk to read point cloud file and reconstruct the surface
file = "cache/d9c5e8ef-7b7f-485e-8fc8-23098c32afcb.ply"
reader = vtk.vtkPLYReader()
reader.SetFileName(file)
reader.Update()
delaunay = vtk.vtkDelaunay2D()
delaunay.SetAlpha(0.1)
delaunay.SetTolerance(0.0001)
delaunay.SetOffset(1.25)
delaunay.BoundingTriangulationOff()
delaunay.SetInputData(reader.GetOutput())
delaunay.Update()
#Once finish reading and processing the point cloud, pass to the next function for rendering
wx.CallAfter(self.AfterProcess, delaunay)
def AfterProcess(self, data):
meshVisGui = MesVisGUI.MeshVisGui(data)
meshVisGui.Show()
def OnEnter(self, event):
#Event listener when user click on Enter button
my_thread = threading.Thread(target=self.testShowGUI)
my_thread.start()
The code for the separate frame is as below:
class MeshVisGui(wx.Frame):
SPACING = 4
def __init__(self, delaunay, parent=None):
self.delaunayData = delaunay
self.title = "Mesh Visualization"
wx.Frame.__init__(self, None, -1, self.title)
self.Initialize()
def Initialize(self):
self.panel = wx.Panel(self, -1, size=(600, 400), style=wx.BORDER_RAISED)
self.widget3d = wxVTKRenderWindowInteractor(self.panel, -1)
self.widget3d.Enable()
self.render = vtk.vtkRenderer()
self.render.SetBackground(params.BackgroundColor)
self.widget3d.GetRenderWindow().AddRenderer(self.render)
self.interactor = self.widget3d.GetRenderWindow().GetInteractor()
self.interactor.GetInteractorStyle().SetCurrentStyleToTrackballCamera()
self.axesWidget = utils.createAxes(self.interactor)
self.meshActor = utils.build_actor(self.delaunayData)
self.render.AddActor(self.meshActor)
self.render.ResetCamera()
box = wx.BoxSizer(wx.VERTICAL)
box.Add(self.widget3d, 1, wx.EXPAND, self.SPACING)
self.panel.SetSizer(box)
self.Layout()
However, on my main UI, it is still showing a spinning icon and block the UI while it is trying to process the point cloud data. Can someone help me spot what I have done wrong?
Wxpython version: 4.0.1
Python version: 3.6.5
Following on from Mike Driscoll's answer and comment, here is a sample of a threaded task running from another panel.
The thread reports back to the 2nd panel (it's parent) using an event. This allows a progress bar to be updated.
The 2nd panel includes a "Cancel" option for the threaded task, whilst the main frame has a button to test if it is not frozen.
The use of wx.GetApp().Yield() may be slightly old fashioned but I have always found it to be reliable.
import time
import wx
from threading import Thread
import wx.lib.newevent
progress_event, EVT_PROGRESS_EVENT = wx.lib.newevent.NewEvent()
class ThreadFrame(wx.Frame):
def __init__(self, title, parent=None):
wx.Frame.__init__(self, parent=parent, title=title)
panel = wx.Panel(self)
self.btn = wx.Button(panel,label='Stop Long running process', size=(200,30), pos=(10,10))
self.btn.Bind(wx.EVT_BUTTON, self.OnExit)
self.progress = wx.Gauge(panel,size=(300,10), pos=(10,50), range=300)
#Bind to the progress event issued by the thread
self.Bind(EVT_PROGRESS_EVENT, self.OnProgress)
#Bind to Exit on frame close
self.Bind(wx.EVT_CLOSE, self.OnExit)
self.Show()
self.mythread = TestThread(self)
#Enable the GUI to be responsive by briefly returning control to the main App
while self.mythread.isAlive():
time.sleep(0.1)
wx.GetApp().Yield()
continue
try:
self.OnExit(None)
except:
pass
def OnProgress(self, event):
self.progress.SetValue(event.count)
#or for indeterminate progress
#self.progress.Pulse()
def OnExit(self, event):
if self.mythread.isAlive():
self.mythread.terminate() # Shutdown the thread
self.mythread.join() # Wait for it to finish
self.Destroy()
class TestThread(Thread):
def __init__(self,parent_target):
Thread.__init__(self)
self.parent = parent_target
self.stopthread = False
self.time = time.time()
self.start() # start the thread
def run(self):
# A loop that will run for 5 minutes then terminate
while self.stopthread == False:
curr_loop = int(time.time() - self.time)
if curr_loop < 300:
time.sleep(1)
evt = progress_event(count=curr_loop)
#Send back current count for the progress bar
try:
wx.PostEvent(self.parent, evt)
except: # The parent frame has probably been destroyed
self.terminate()
else:
self.terminate()
def terminate(self):
self.stopthread = True
class MyPanel(wx.Panel):
def __init__(self, parent):
wx.Panel.__init__(self, parent)
self.text_count = 0
self.parent=parent
btn = wx.Button(self, wx.ID_ANY, label='Start Long running process', size=(200,30), pos=(10,10))
btn.Bind(wx.EVT_BUTTON, self.Thread_Frame)
btn2 = wx.Button(self, wx.ID_ANY, label='Is the GUI still active?', size=(200,30), pos=(10,50))
btn2.Bind(wx.EVT_BUTTON, self.AddText)
self.txt = wx.TextCtrl(self, wx.ID_ANY, style= wx.TE_MULTILINE, pos=(10,90),size=(400,100))
def Thread_Frame(self, event):
frame = ThreadFrame(title='Threaded Task', parent=self.parent)
def AddText(self,event):
self.text_count += 1
txt = self.txt.GetValue()
txt += "More text " + str(self.text_count)+"\n"
self.txt.SetValue(txt)
class MainFrame(wx.Frame):
def __init__(self):
wx.Frame.__init__(self, None, title='Main Frame', size=(600,400))
panel = MyPanel(self)
self.Show()
if __name__ == '__main__':
app = wx.App(False)
frame = MainFrame()
app.MainLoop()
You do not need threads to open new frames / windows in your wxPython application. You just need to create a sub-class of wx.Frame to hold the code of your other frame. Then from your main application's frame, you can instantiate the other frame and show it. You use the same concept when you create a wx.Dialog or a wx.MessageDialog.
Here is a simple example:
import wx
class OtherFrame(wx.Frame):
"""
Class used for creating frames other than the main one
"""
def __init__(self, title, parent=None):
wx.Frame.__init__(self, parent=parent, title=title)
self.Show()
class MyPanel(wx.Panel):
def __init__(self, parent):
wx.Panel.__init__(self, parent)
btn = wx.Button(self, label='Create New Frame')
btn.Bind(wx.EVT_BUTTON, self.on_new_frame)
def on_new_frame(self, event):
frame = OtherFrame(title='SubFrame',
parent=wx.GetTopLevelParent(self))
class MainFrame(wx.Frame):
def __init__(self):
wx.Frame.__init__(self, None, title='Main Frame')
panel = MyPanel(self)
self.Show()
if __name__ == '__main__':
app = wx.App(False)
frame = MainFrame()
app.MainLoop()
In this example, I set the other frame's parent to the MainFrame instance by using wx.GetTopLevelParent(self). The benefit of setting a parent for the sub-frames is that if I close the main frame, it will cause the other frames to also be closed.

pyqt5: why the mimeData().text() returns nothing?

learning PyQt5 recently, I've tried to drag a QPushButton learning this tutorial Drag & drop a button widget, and made some improvements to place the button more accurate, so I add
mime = e.mimeData().text()
x, y = mime.split(',')
according to #Avaris for this question, but I found e.mimeData().text() returned nothing which supposed to be the coordinate of local position of the cursor with respect to the button, i tried to print(mime), and got a blank line with nothing, then i print(mime.split(',')) and got ['']。
here's the code:
import sys
from PyQt5.QtWidgets import QPushButton, QWidget, QApplication, QLabel
from PyQt5.QtCore import Qt, QMimeData
from PyQt5.QtGui import QDrag
from PyQt5 import QtCore
class Button(QPushButton):
def __init__(self, title, parent):
super().__init__(title, parent)
def mouseMoveEvent(self, e):
if e.buttons() != Qt.RightButton:
return
mimeData = QMimeData()
drag = QDrag(self)
drag.setMimeData(mimeData)
dropAction = drag.exec_(Qt.MoveAction)
def mousePressEvent(self, e):
QPushButton.mousePressEvent(self, e)
if e.button() == Qt.LeftButton:
print('press')
class Example(QWidget):
def __init__(self):
super().__init__()
self.initUI()
def initUI(self):
self.setAcceptDrops(True)
self.button = Button('Button', self)
self.button.move(100, 65)
self.setWindowTitle('Click or Move')
self.setGeometry(300, 300, 280, 150)
def dragEnterEvent(self, e):
e.accept()
def dropEvent(self, e):
position = e.pos()
mime = e.mimeData().text()
x, y = mime.split(',')
#print(mime.split(','))
self.button.move(position - QtCore.QPoint(int(x), int(y)))
e.setDropAction(Qt.MoveAction)
e.accept()
if __name__ == '__main__':
app = QApplication(sys.argv)
ex = Example()
ex.show()
app.exec_()
In the answer of #Avaris, you will notice they set the mimedata with the button position in the mouseMoveEvent:
mimeData = QtCore.QMimeData()
# simple string with 'x,y'
mimeData.setText('%d,%d' % (e.x(), e.y()))
The mimedata does not contain anything by default. You have to set everything yourself! Have a look at the documentation for QMimeData to see what else you can do (other than setting arbitrary text)
Drag and Drop in Camera View
def dragEnterEvent(self, event): # Drag lines
mimeData = QtCore.QMimeData()
if mimeData.hasText:
event.accept()
else:
event.ignore()
def dropEvent(self, event): # Drop lines
mimeData = QtCore.QMimeData()
format = 'application/x-qabstractitemmodeldatalist'
data=event.mimeData().data(format) # Drag Drop get data's name
name_str = codecs.decode(data,'utf-8') # Convert byte to string
mimeData.setText(name_str)
# print(name_str[26:].replace('\x00','').strip("")) # remove white space
if mimeData.hasText:
print(name_str)
# write what you will do

wxpyton - threads in many modules

I'm trying to create simple frame that will run longrun procedure, but will show counting in different window (dialog), but it don't work (staticText1 is not updating)... Here's my code:
Main frame (simple frame with one button)
import wx
import time
from threading import Thread
import Dialog1
def create(parent):
return Frame1(parent)
[wxID_FRAME1, wxID_FRAME1BUTTON1, ] = [wx.NewId() for _init_ctrls in range(2)]
class Frame1(wx.Frame):
def test1(self):
for i in range(self.delays):
time.sleep(1)
def _init_ctrls(self, prnt):
# generated method, don't edit
wx.Frame.__init__(self, id=wxID_FRAME1, name='', parent=prnt,
pos=wx.Point(589, 259), size=wx.Size(178, 128),
style=wx.DEFAULT_FRAME_STYLE, title='Frame1')
self.button1 = wx.Button(id=wxID_FRAME1BUTTON1, label='button1',
name='button1', parent=self, pos=wx.Point(0, 0), size=wx.Size(178,
128), style=0)
self.button1.Bind(wx.EVT_BUTTON, self.OnButton1Button,
id=wxID_FRAME1BUTTON1)
def __init__(self, parent):
self._init_ctrls(parent)
self.delays = 5
self.timer = wx.Timer(self)
def OnButton1Button(self, event):
self.testThread = Thread(target=self.test1)
self.testThread.start()
#self.Show(False)
self.dlg = Dialog1.Dialog1(self)
self.dlg.ShowModal()
self.button1.Disable()
self.Bind(wx.EVT_TIMER, self.PollThread)
self.timer.Start(20, oneShot=True)
event.Skip()
def PollThread(self, event):
if self.testThread.isAlive():
self.Bind(wx.EVT_TIMER, self.PollThread)
self.timer.Start(200, oneShot=True)
self.dlg.staticText1.SetLabel(self.dlg.staticText1.GetLabel()+".")
else:
self.button1.Enable()
self.dlg.Destroy()
Dialog (simple dialog with one statictext):
import wx
def create(parent):
return Dialog1(parent)
[wxID_DIALOG1, wxID_DIALOG1STATICTEXT1, ] = [wx.NewId() for _init_ctrls in range(2)]
class Dialog1(wx.Dialog):
def _init_ctrls(self, prnt):
# generated method, don't edit
wx.Dialog.__init__(self, id=wxID_DIALOG1, name='', parent=prnt,
pos=wx.Point(451, 295), size=wx.Size(544, 59),
style=wx.DEFAULT_DIALOG_STYLE, title='Dialog1')
self.staticText1 = wx.StaticText(id=wxID_DIALOG1STATICTEXT1,
label=u'Please wait', name='staticText1', parent=self,
pos=wx.Point(56, 24), size=wx.Size(95, 17), style=0)
def __init__(self, parent):
self._init_ctrls(parent)

wxPython threading downloads

I need to download a list of urls in a wxPython application, but I'm really new to threading, could anyone show me a working example of how to download links and put the output in a wx control.
It would have been nice to see what you had done to at least try to accomplish this. Anyway, there are a couple of good resources for learning how to do threads in wxPython. Here they are:
wiki.wxpython.org/LongRunningTasks
http://www.blog.pythonlibrary.org/2010/05/22/wxpython-and-threads/
I wrote up a tutorial on downloading files using urllib/urllib2 and requests here:
http://www.blog.pythonlibrary.org/2012/06/07/python-101-how-to-download-a-file/
If you combine these three articles together, you can come up with your answer. However, I went ahead and wrote up a super simple downloader:
import requests
import os
import wx
import wx.lib.scrolledpanel as scrolled
from threading import Thread
from wx.lib.pubsub import pub
########################################################################
class DownloadThread(Thread):
"""Downloading thread"""
#----------------------------------------------------------------------
def __init__(self, gnum, url, fsize):
"""Constructor"""
Thread.__init__(self)
self.fsize = fsize
self.gnum = gnum
self.url = url
self.start()
#----------------------------------------------------------------------
def run(self):
"""
Run the worker thread
"""
local_fname = os.path.basename(self.url)
count = 1
while True:
if os.path.exists(local_fname):
tmp, ext = os.path.splitext(local_fname)
cnt = "(%s)" % count
local_fname = tmp + cnt + ext
count += 1
else:
break
req = requests.get(self.url, stream=True)
total_size = 0
print local_fname
with open(local_fname, "wb") as fh:
for byte in req.iter_content(chunk_size=1024):
if byte:
fh.write(byte)
fh.flush()
total_size += 1024
if total_size < self.fsize:
wx.CallAfter(pub.sendMessage,
"update_%s" % self.gnum,
msg=total_size)
print "DONE!"
wx.CallAfter(pub.sendMessage,
"update_%s" % self.gnum,
msg=self.fsize)
########################################################################
class MyGauge(wx.Gauge):
""""""
#----------------------------------------------------------------------
def __init__(self, parent, range, num):
"""Constructor"""
wx.Gauge.__init__(self, parent, range=range)
pub.subscribe(self.updateProgress, "update_%s" % num)
#----------------------------------------------------------------------
def updateProgress(self, msg):
""""""
self.SetValue(msg)
########################################################################
class MyPanel(scrolled.ScrolledPanel):
""""""
#----------------------------------------------------------------------
def __init__(self, parent):
"""Constructor"""
scrolled.ScrolledPanel.__init__(self, parent)
self.data = []
self.download_number = 1
# create the sizers
self.main_sizer = wx.BoxSizer(wx.VERTICAL)
dl_sizer = wx.BoxSizer(wx.HORIZONTAL)
# create the widgets
lbl = wx.StaticText(self, label="Download URL:")
self.dl_txt = wx.TextCtrl(self)
btn = wx.Button(self, label="Download")
btn.Bind(wx.EVT_BUTTON, self.onDownload)
# layout the widgets
dl_sizer.Add(lbl, 0, wx.ALL|wx.CENTER, 5)
dl_sizer.Add(self.dl_txt, 1, wx.EXPAND|wx.ALL, 5)
dl_sizer.Add(btn, 0, wx.ALL, 5)
self.main_sizer.Add(dl_sizer, 0, wx.EXPAND)
self.SetSizer(self.main_sizer)
self.SetAutoLayout(1)
self.SetupScrolling()
#----------------------------------------------------------------------
def onDownload(self, event):
"""
Update display with downloading gauges
"""
url = self.dl_txt.GetValue()
try:
header = requests.head(url)
fsize = int(header.headers["content-length"]) / 1024
sizer = wx.BoxSizer(wx.HORIZONTAL)
fname = os.path.basename(url)
lbl = wx.StaticText(self, label="Downloading %s" % fname)
gauge = MyGauge(self, fsize, self.download_number)
sizer.Add(lbl, 0, wx.ALL|wx.CENTER, 5)
sizer.Add(gauge, 0, wx.ALL|wx.EXPAND, 5)
self.main_sizer.Add(sizer, 0, wx.EXPAND)
self.Layout()
# start thread
DownloadThread(self.download_number, url, fsize)
self.download_number += 1
except Exception, e:
print "Error: ", e
########################################################################
class DownloaderFrame(wx.Frame):
""""""
#----------------------------------------------------------------------
def __init__(self):
"""Constructor"""
wx.Frame.__init__(self, None, title="Downloader", size=(800, 400))
panel = MyPanel(self)
self.Show()
#----------------------------------------------------------------------
if __name__ == "__main__":
app = wx.App(False)
frame = DownloaderFrame()
app.MainLoop()
Note: You will need requests to use this script.

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