Drawing with cairo in wxpython - python

am fairly new to python and am trying to write a simple program using cairo and wxpython. I am used to using cairo with gtk and C, but am finiding myself confused.
I have built myself a simple ui with the following code:
import wx
class Frame(wx.Frame):
def __init__(self, *args, **kwargs):
super(Frame, self).__init__(*args, **kwargs)
self.InitUI()
def InitUI(self):
#----------------------------------------------------
# Build menu bar and submenus
menubar = wx.MenuBar()
# file menu containing quit menu item
fileMenu = wx.Menu()
quit_item = wx.MenuItem(fileMenu, wx.ID_EXIT, '&Quit\tCtrl+W')
fileMenu.AppendItem(quit_item)
self.Bind(wx.EVT_MENU, self.OnQuit, quit_item)
menubar.Append(fileMenu, '&File')
# help menu containing about menu item
helpMenu = wx.Menu()
about_item = wx.MenuItem(helpMenu, wx.ID_ABOUT, '&About\tCtrl+A')
helpMenu.AppendItem(about_item)
self.Bind(wx.EVT_MENU, self.OnAboutBox, about_item)
menubar.Append(helpMenu, '&Help')
self.SetMenuBar(menubar)
#----------------------------------------------------
# Build window layout
panel = wx.Panel(self)
#panel.SetBackgroundColour('yellow')
vbox = wx.BoxSizer(wx.VERTICAL)
panel.SetSizer(vbox)
midPan = wx.Panel(panel)
#midPan.SetBackgroundColour('blue')
hbox = wx.BoxSizer(wx.HORIZONTAL)
vbox.Add(midPan, 1, wx.EXPAND | wx.ALL, 12)
midPan.SetSizer(hbox)
smallPan = wx.Panel(panel)
#smallPan.SetBackgroundColour('red')
hbox2 = wx.BoxSizer(wx.HORIZONTAL)
vbox.Add(smallPan, 0, wx.ALIGN_RIGHT|wx.LEFT|wx.RIGHT|wx.BOTTOM, 12)
smallPan.SetSizer(hbox2)
#----------------------------------------------------
# Place buttons in correct box corresponding with panel
close_button = wx.Button(smallPan, wx.ID_CLOSE)
self.Bind(wx.EVT_BUTTON, self.OnQuit, close_button)
hbox2.Add(close_button)
#----------------------------------------------------
# Set window properties
self.SetSize((1600, 1200))
self.SetTitle('PROGRAM NAME')
self.Centre()
def OnQuit(self, e):
self.Close()
def main():
ex = wx.App()
f = Frame(None)
f.Show(True)
ex.MainLoop()
if __name__ == '__main__':
main()
I would like to be able to draw in the panel named midPan. How do I go about adding the OnDraw function and linking up the signal handler?
I greatly appreciate the help.

If you are used to procedural programming then the confusion
is natural. Python is an OOP language and coding in an OOP
language is quite different. I have cleaned and updated the
provided example. The panel that is used as a drawing area
paints three coloured rectangles. You have not provided the
implementation of the OnAboutBox() method, therefore, I have
commented out the line.
#!/usr/bin/python
import wx
import wx.lib.wxcairo
import cairo
class DrawingArea(wx.Panel):
def __init__ (self , *args , **kw):
super(DrawingArea , self).__init__ (*args , **kw)
self.SetDoubleBuffered(True)
self.Bind(wx.EVT_PAINT, self.OnPaint)
def OnPaint(self, e):
dc = wx.PaintDC(self)
cr = wx.lib.wxcairo.ContextFromDC(dc)
self.DoDrawing(cr)
def DoDrawing(self, cr):
cr.set_source_rgb (0.2 , 0.23 , 0.9)
cr.rectangle(10 , 15, 90, 60)
cr.fill()
cr.set_source_rgb(0.9 , 0.1 , 0.1)
cr.rectangle(130 , 15, 90, 60)
cr.fill()
cr.set_source_rgb(0.4 , 0.9 , 0.4)
cr.rectangle(250 , 15, 90, 60)
cr.fill()
class Frame(wx.Frame):
def __init__(self, *args, **kwargs):
super(Frame, self).__init__(*args, **kwargs)
self.InitUI()
def InitUI(self):
#----------------------------------------------------
# Build menu bar and submenus
menubar = wx.MenuBar()
# file menu containing quit menu item
fileMenu = wx.Menu()
quit_item = wx.MenuItem(fileMenu, wx.ID_EXIT, '&Quit\tCtrl+W')
fileMenu.AppendItem(quit_item)
self.Bind(wx.EVT_MENU, self.OnQuit, quit_item)
menubar.Append(fileMenu, '&File')
# help menu containing about menu item
helpMenu = wx.Menu()
about_item = wx.MenuItem(helpMenu, wx.ID_ABOUT, '&About\tCtrl+A')
helpMenu.AppendItem(about_item)
#~ self.Bind(wx.EVT_MENU, self.OnAboutBox, about_item)
menubar.Append(helpMenu, '&Help')
self.SetMenuBar(menubar)
#----------------------------------------------------
# Build window layout
panel = wx.Panel(self)
vbox = wx.BoxSizer(wx.VERTICAL)
panel.SetSizer(vbox)
midPan = DrawingArea(panel)
vbox.Add(midPan, 1, wx.EXPAND | wx.ALL, 12)
smallPan = wx.Panel(panel)
hbox2 = wx.BoxSizer(wx.HORIZONTAL)
vbox.Add(smallPan, 1, wx.EXPAND|wx.ALL, 12)
smallPan.SetSizer(hbox2)
#----------------------------------------------------
# Place buttons in correct box corresponding with panel
close_button = wx.Button(smallPan, wx.ID_CLOSE)
self.Bind(wx.EVT_BUTTON, self.OnQuit, close_button)
hbox2.Add(close_button)
#----------------------------------------------------
# Set window properties
#~ self.SetSize((1600, 1200))
self.SetSize((400, 250))
#~ self.Maximize()
self.SetTitle('PROGRAM NAME')
self.Centre()
def OnQuit(self, e):
self.Close()
def main():
ex = wx.App()
f = Frame(None)
f.Show(True)
ex.MainLoop()
if __name__ == '__main__':
main()
To do the drawing, we create a custom class that will serve as a
drawing area. It inherits from a wx.Panel widget.
class DrawingArea(wx.Panel):
def __init__ (self , *args , **kw):
super(DrawingArea , self).__init__ (*args , **kw)
self.SetDoubleBuffered(True)
self.Bind(wx.EVT_PAINT, self.OnPaint)
...
This is our custom class used for drawing. In the constructor
we bind the paint event to the OnPaint() method.
def OnPaint(self, e):
dc = wx.PaintDC(self)
cr = wx.lib.wxcairo.ContextFromDC(dc)
self.DoDrawing(cr)
Inside the OnPaint() method we create a cairo drawing
context and delegate the actual drawing code to the DoDrawing()
method.
midPan = DrawingArea(panel)
vbox.Add(midPan, 1, wx.EXPAND | wx.ALL, 12)
The drawing area is created and added to the vertical box.
#~ self.SetSize((1600, 1200))
self.SetSize((400, 250))
#~ self.Maximize()
Final note: if you want to show the window maximized, call the Maximize()
method. Computer screens have different sizes.

As explained in Very Simple Drawing example, use wx.EVT_PAINT;
add OnPaint binding to your midPan:
# (...)
midPan = wx.Panel(panel)
#midPan.SetBackgroundColour('blue')
hbox = wx.BoxSizer(wx.HORIZONTAL)
vbox.Add(midPan, 1, wx.EXPAND | wx.ALL, 12)
midPan.SetSizer(hbox)
# binding here:
midPan.Bind(wx.EVT_PAINT, self.OnPaint)
# (...) rest of code
and define your OnPaint code:
# (...)
def OnQuit(self, e):
self.Close()
# your OnPaint():
def OnPaint(self,event):
dc = wx.PaintDC(event.GetEventObject())
dc.Clear()
# set up your pen
dc.SetPen(wx.Pen("BLACK", 4))
# draw whatever you like
dc.DrawLine(0, 0, 50, 50)
# (...) rest of code

Related

Make TextCtrl Scale with Window

I've just gotten into wxpython for Python 3.6 and I've hit a roadblock. I just can't work out how to make elements/widgets scale with the screen! I know you have to use sizers but that's about it, I'm still fairly new to programming so just reading the documentation didn't help. If someone could just sample some code that works I'd be very thankful as I could then read through it and work out what I was doing wrong. The code that draws out the GUI I want to scale with window size is below, the key idea is that the TextCtrl scales, other elements don't really need scaling.
def createGUI(self):
panel = wx.Panel(self)
menuBar = wx.MenuBar()
menuButton = wx.Menu()
newItem = wx.MenuItem(menuButton, wx.ID_NEW, 'New Note\tCtrl+N')
delItem = wx.MenuItem(menuButton, wx.ID_DELETE, 'Delete Note\tCtrl+Backspace')
saveItem = wx.MenuItem(menuButton, wx.ID_SAVE, 'Save\tCtrl+S')
exitItem = wx.MenuItem(menuButton, wx.ID_EXIT, 'Quit\tCtrl+Q')
menuButton.Append(newItem)
menuButton.Append(saveItem)
menuButton.Append(delItem)
menuButton.Append(exitItem)
menuBar.Append(menuButton, 'Menu')
self.SetMenuBar(menuBar)
self.Bind(wx.EVT_MENU, self.new, newItem)
self.Bind(wx.EVT_MENU, self.delete, delItem)
self.Bind(wx.EVT_MENU, self.save, saveItem)
self.Bind(wx.EVT_MENU, self.onExit, exitItem)
self.noteText = wx.TextCtrl(panel)
self.noteText.AppendText(self.notecontent)
self.Bind(wx.EVT_CLOSE, self.onExit)
self.SetTitle(f'Welcome {self.username}! You are working on {self.notepath}')
self.Centre()
self.Show(True)
To begin with it's best to equate sizers to something familiar and I usually think of storage boxes or a chest of drawers.
When we define widgets, they are all dumped into a container, the parent object, often the ubiquitous self or self.panel.
If we do not assign a size and pos to each item, it's just a jumbled mess, a pile of widgets.
The sizer, there are many types, are the virtual drawers in our chest of drawers, that herds this pile of widgets into order.
The widgets are assigned to the appropriate sizer, note sizers can go into other sizers, and eventually when everything has been assigned a place or drawer in our chest of drawers, the sizers do their magic, arranging and sizing all of widgets into a coherent screen for display or arranging the drawers contents and relative positions in the chest of drawers.
Below, I've used the simplest sizer a boxsizer.
One will arrange things vertically and the other horizontally.
The horizontal sizer is for the buttons and the vertical sizer, will be the main sizer, into which I place not only the TectCtrl but also the buttons, prearranged in their horizontal sizer.
For a better and more comprehensive description of sizers and their controls see: https://docs.wxpython.org/sizers_overview.html and for details on the actual sizers available see the detailed documenation on each.
A loose approximation of your code:
#!/usr/bin/python
import wx
class Example(wx.Frame):
def __init__(self, parent, title):
super(Example, self).__init__(parent, title=title,
size=(450, 350))
self.panel = wx.Panel(self, -1)
self.main_sizer = wx.BoxSizer(wx.VERTICAL)
self.button_sizer = wx.BoxSizer(wx.HORIZONTAL)
self.noteText = wx.TextCtrl(self.panel, -1, style=wx.TE_MULTILINE)
self.Button_close = wx.Button(self.panel, -1, label="Quit")
self.Button_1 = wx.Button(self.panel, -1, label="Btn1")
self.Button_2 = wx.Button(self.panel, -1, label="Btn2")
self.Bind(wx.EVT_CLOSE, self.onExit)
self.Button_close.Bind(wx.EVT_BUTTON, self.onExit)
self.Button_1.Bind(wx.EVT_BUTTON, self.onButton)
self.Button_2.Bind(wx.EVT_BUTTON, self.onButton)
# Place buttons within their own horizontal sizer
self.button_sizer.Add(self.Button_close,proportion=0, flag=wx.ALL, border=10)
self.button_sizer.Add(self.Button_1,proportion=0, flag=wx.ALL, border=10)
self.button_sizer.Add(self.Button_2,proportion=0, flag=wx.ALL, border=10)
# Add textctrl and the button sizer to the main sizer (vertical)
self.main_sizer.Add(self.noteText,proportion=1, flag=wx.EXPAND|wx.ALL, border=10)
self.main_sizer.Add(self.button_sizer, 0, 0, 0)
self.panel.SetSizer(self.main_sizer)
self.Show()
def onExit(self, event):
self.Destroy()
def onButton(self, event):
print("A button was pressed")
if __name__ == '__main__':
app = wx.App()
Example(None, title="Example")
app.MainLoop()
Edit:
Here's the same code without using sizers, although they are recommended.
#!/usr/bin/python
import wx
class Example(wx.Frame):
def __init__(self, parent, title):
super(Example, self).__init__(parent, title=title,
size=(450, 350))
self.panel = wx.Panel(self, -1)
self.noteText = wx.TextCtrl(self.panel, -1, pos=(10,10), size=(400,280), style=wx.TE_MULTILINE)
self.Button_close = wx.Button(self.panel, -1, label="Quit", pos=(10,290), size=(50,30))
self.Button_1 = wx.Button(self.panel, -1, label="Btn1", pos=(70,290), size=(50,30))
self.Button_2 = wx.Button(self.panel, -1, label="Btn2", pos=(130,290), size=(50,30))
self.Bind(wx.EVT_CLOSE, self.onExit)
self.Button_close.Bind(wx.EVT_BUTTON, self.onExit)
self.Button_1.Bind(wx.EVT_BUTTON, self.onButton)
self.Button_2.Bind(wx.EVT_BUTTON, self.onButton)
self.Show()
def onExit(self, event):
self.Destroy()
def onButton(self, event):
print("A button was pressed")
if __name__ == '__main__':
app = wx.App()
Example(None, title="Example")
app.MainLoop()

wx.Frame error when calling one script from another

The following is a bit of copied code from another question, it works fine as a standalone app, but the pop-up right-click menu references frame_1 which is not available if "if name == 'main':" is false, as it is when the program is called by another. What should this reference be changed to?
Thanks.
import wx
import sys
sys.path.append("..")
from ObjectListView import ObjectListView, ColumnDefn
### 2. Launcher creates wxMenu. ###
menu_titles = [ "Open",
"Properties",
"Rename",
"Delete" ]
menu_title_by_id = {}
for title in menu_titles:
menu_title_by_id[ wx.NewId() ] = title
class Track(object):
"""
Simple minded object that represents a song in a music library
"""
def __init__(self, title, artist, album):
self.title = title
self.artist = artist
self.album = album
def GetTracks():
"""
Return a collection of tracks
"""
return [
Track("Sweet Lullaby", "Deep Forest", "Deep Forest"),
Track("Losing My Religion", "U2", "Out of Time"),
Track("En el Pais de la Libertad", "Leon Gieco", "Leon Gieco"),
]
class MyFrame(wx.Frame):
def __init__(self, *args, **kwds):
wx.Frame.__init__(self, *args, **kwds)
self.Init()
def Init(self):
self.InitModel()
self.InitWidgets()
self.InitObjectListView()
def InitModel(self):
self.songs = GetTracks()
def InitWidgets(self):
panel = wx.Panel(self, -1)
sizer_1 = wx.BoxSizer(wx.VERTICAL)
sizer_1.Add(panel, 1, wx.ALL | wx.EXPAND)
self.SetSizer(sizer_1)
self.myOlv = ObjectListView(panel, -1, style=wx.LC_REPORT | wx.SUNKEN_BORDER)
sizer_2 = wx.BoxSizer(wx.VERTICAL)
sizer_2.Add(self.myOlv, 1, wx.ALL | wx.EXPAND, 4)
panel.SetSizer(sizer_2)
self.Layout()
def InitObjectListView(self):
self.myOlv.SetColumns([
ColumnDefn("Title", "left", 120, "title"),
ColumnDefn("Artist", "left", 100, "artist"),
ColumnDefn("Album", "left", 100, "album")
])
self.myOlv.SetObjects(self.songs)
self.myOlv.Bind(wx.EVT_LIST_ITEM_RIGHT_CLICK, self.RightClick)
def RightClick(self, event):
# record what was clicked
self.list_item_clicked = self.myOlv.GetSelectedObject()
menu = wx.Menu()
menu.Bind(wx.EVT_MENU, self.MenuSelectionCb)
for (id_, title) in menu_title_by_id.items():
### 3. Launcher packs menu with Append. ###
menu.Append(id_, title)
### 5. Launcher displays menu with call to PopupMenu, invoked on the source component, passing event's GetPoint. ###
# self.frame.PopupMenu( menu, event.GetPoint() )
frame_1.PopupMenu(menu, event.GetPoint())
menu.Destroy() # destroy to avoid mem leak
def MenuSelectionCb(self, event):
# do something
operation = menu_title_by_id[ event.GetId() ]
target = self.list_item_clicked.title
print 'Perform "%(operation)s" on "%(target)s."' % vars()
class MyPopupMenu(wx.Menu):
def __init__(self, parent):
super(MyPopupMenu, self).__init__()
self.parent = parent
mmi = wx.MenuItem(self, wx.NewId(), 'Minimize')
self.AppendItem(mmi)
self.Bind(wx.EVT_MENU, self.OnMinimize, mmi)
cmi = wx.MenuItem(self, wx.NewId(), 'Close')
self.AppendItem(cmi)
self.Bind(wx.EVT_MENU, self.OnClose, cmi)
def OnMinimize(self, e):
self.parent.Iconize()
def OnClose(self, e):
self.parent.Close()
if __name__ == '__main__':
app = wx.App(True)
wx.InitAllImageHandlers()
frame_1 = MyFrame(None, -1, "ObjectListView Track Test")
app.SetTopWindow(frame_1)
frame_1.Show()
app.MainLoop()
If you are going to import your code into another module, then you will just need to instantiate that frame in your new main application's code. Let's save your code as olv_tracks.py. Now import it like I do in the following code:
import wx
import olv_tracks
class MyFrame(wx.Frame):
def __init__(self):
wx.Frame.__init__(self, None, title='Main App')
panel = wx.Panel(self)
self.Show()
# show other frame
frame = olv_tracks.MyFrame(None, -1, "ObjectListView Track Test")
frame.Show()
if __name__ == '__main__':
app = wx.App(False)
frame = MyFrame()
app.MainLoop()
Now you just instantiate the frame the same way you did in your code.
Also, you need to change the reference to frame_1 in your RightClick method to self. So instead of frame_1.PopupMenu(menu, event.GetPoint()), it should be self.PopupMenu(menu, event.GetPoint())

How can I make a wxpython Widget span two cells without pushing other widgets aside?

I'm trying to make a form that has several input fields. Underneath these fields I want to have a wxpython Ultimate List Control (for all intents and purposes it's the same thing as a List Control). My issue is with sizers. To give some context, my form looks like this
Name [TextCtrl]
Blah [TextCtrl]
ListControl
I want it to look like
Name [TextCtrl]
Blah [TextCtrl]
ListCtrl (this spans to the end of the row)
My problem is when I try to add the List Control. I want the list control to Stretch from The Static Text to the Text Control, but it pushes the TextControl over. Can someone please point me in the right direction? I have attached the relevant code below.
class UserField(wx.Dialog):
def __init__(self, parent):
wx.Dialog.__init__(self, parent=parent, title="Info", size=(350, 400),
style=wx.DEFAULT_FRAME_STYLE)
self.init_ui()
self.Center()
self.ShowModal()
def init_ui(self):
panel = wx.Panel(self, wx.ID_ANY)
hbox = wx.BoxSizer(wx.VERTICAL)
flex_grid = wx.FlexGridSizer(5, 2, 5, 10) # row, col, vgap, hgap
info_text = wx.StaticText(parent=panel, label="Enter information")
self.search_button = wx.Button(parent=panel, label="Search")
self.list_control = UltimateListCtrl(panel,
agwStyle=wx.LC_REPORT | wx.BORDER_SUNKEN | ULC_HAS_VARIABLE_ROW_HEIGHT, )
flex_grid.AddMany(
[
info_text, self.search_button
]
)
lbox = wx.BoxSizer(wx.HORIZONTAL)
lbox.Add(self.list_control
hbox.Add(flex_grid, wx.EXPAND|wx.ALL)
hbox.Add(lbox, proportion=1, flag=wx.ALL|wx.EXPAND)
panel.SetSizer(hbox)
Here's a quick demonstration of wx.GridBagSizer. The program opens a simple frame with a single button that spawns a dialog with a GridBagSizer. You can place items in the sizer according to a position (pos) and optionally allow a widget to span multiple rows and/or columns (span).
import wx
class Example(wx.Frame):
def __init__(self, *args, **kwargs):
wx.Frame.__init__(self, *args, **kwargs)
self.SetSize((300, 200))
self.Centre()
self.Show(True)
self.InitUI()
def InitUI(self):
panel = wx.Panel(self)
sizer = wx.BoxSizer()
btn = wx.Button(panel, label="Spawn Window")
btn.Bind(wx.EVT_BUTTON, self.spawn_window)
sizer.Add(btn)
panel.SetSizerAndFit(sizer)
def spawn_window(self, evt):
UserField(self)
def OnQuit(self, e):
self.Close()
class UserField(wx.Dialog):
def __init__(self, parent):
wx.Dialog.__init__(self, parent=parent, title="Info", size=(350, 400),
style=wx.DEFAULT_FRAME_STYLE)
self.init_ui()
self.Center()
self.ShowModal()
def init_ui(self):
panel = wx.Panel(self)
sizer = wx.GridBagSizer(10, 10)
field1Label = wx.StaticText(panel, label="Field 1")
field2Label = wx.StaticText(panel, label="Field 2")
field1Ctrl = wx.TextCtrl(panel)
field2Ctrl = wx.TextCtrl(panel)
listCtrl = wx.ListCtrl(panel)
sizer.Add(field1Label, pos=(0, 0))
sizer.Add(field2Label, pos=(1, 0))
sizer.Add(field1Ctrl, pos=(0, 1))
sizer.Add(field2Ctrl, pos=(1, 1))
# HERE'S THE IMPORTANT LINE. NOTE THE 'span' ARGUMENT:
sizer.Add(listCtrl, pos=(2, 0), span=(1, 2), flag=wx.EXPAND)
panel.SetSizerAndFit(sizer)
if __name__ == '__main__':
ex = wx.App()
mainFrame = Example(None)
ex.MainLoop()

wxpython cut copy and paste throughout the application

I'm developing a small application with multiple TextCtrl and ComboBox widgets. I want that when I press the key Ctrl-C Ctrl-V and Ctrl-X I get the usual behaviour of copying, pasting and cutting in the appropriate entry.
What I obtain right now is that, while I can right-click and have the text copd/past/cutd, I can't through the keybindings or the menu entries. How can I obtain this in a simple way?
Menu keybindings work by default with Alt-first_menu_letter -> submenu_first_letter.
The menu event of the selected item should bind the corresponding event handler:
self.Bind(wx.EVT_MENU, self.on_copy, self.copy)
for a copy method, you first select the text you want to copy with the mouse. Then you can get the widget that is focused (the specific textcontrol with the selected string to be copied) with:
widget = self.FindFocus()
in this way now you can get the selected string from that widget:
self.copied = widget.GetStringSelection()
And the same has to be done for pasting the copied text in the textctrl you situate the cursor.
Here you have a working example:
import wx
class MyFrame(wx.Frame):
def __init__(self, *args, **kwds):
kwds["style"] = wx.DEFAULT_FRAME_STYLE
wx.Frame.__init__(self, *args, **kwds)
self.tctrl_1 = wx.TextCtrl(self, -1, "", style=wx.TE_MULTILINE)
self.tctrl_2 = wx.TextCtrl(self, -1, "", style=wx.TE_MULTILINE)
self.menubar = wx.MenuBar()
self.test = wx.Menu()
self.copy = wx.MenuItem(self.test, wx.NewId(), "copy", "is_going to copy", wx.ITEM_NORMAL)
self.test.AppendItem(self.copy)
self.paste = wx.MenuItem(self.test, wx.NewId(), "paste", "will paste", wx.ITEM_NORMAL)
self.test.AppendItem(self.paste)
self.menubar.Append(self.test, "Test")
self.SetMenuBar(self.menubar)
self.__set_properties()
self.__do_layout()
self.Bind(wx.EVT_MENU, self.on_copy, self.copy)
self.Bind(wx.EVT_MENU, self.on_paste, self.paste)
def __set_properties(self):
self.SetTitle("frame_1")
def __do_layout(self):
sizer_1 = wx.BoxSizer(wx.VERTICAL)
sizer_2 = wx.BoxSizer(wx.HORIZONTAL)
sizer_2.Add(self.tctrl_1, 1, wx.EXPAND, 0)
sizer_2.Add(self.tctrl_2, 1, wx.EXPAND, 0)
sizer_1.Add(sizer_2, 1, wx.EXPAND, 0)
self.SetSizer(sizer_1)
sizer_1.Fit(self)
self.Layout()
def on_copy(self, event):
widget = self.FindFocus()
self.copied = widget.GetStringSelection()
def on_paste(self, event):
widget = self.FindFocus()
widget.WriteText(self.copied)
if __name__ == "__main__":
app = wx.PySimpleApp(0)
frame = MyFrame(None, -1, "")
frame.Show()
app.MainLoop()

How do I Create an instance of a class in another class in Python

I am trying to learn Python and WxPython. I have been a SAS programmer for years. This OOP stuff is slowly coming together but I am still fuzzy on a lot of the concepts. Below is a section of code. I am trying to use a button click to create an instance of another class. Specifically-I have my main panel in one class and I wanted to instance a secondary panel when a user clicked on one of the menu items on the main panel. I made all of this work when the secondary panel was just a function. I can't seem to get ti to work as a class.
Here is the code
import wx
class mainPanel(wx.Frame):
def __init__(self, parent, id, title):
wx.Frame.__init__(self, parent, id, 'directEDGAR Supplemental Tools', size=(450, 450))
wx.Panel(self,-1)
wx.StaticText(self,-1, "This is where I will describe\n the purpose of these tools",(100,10))
menubar = wx.MenuBar()
parser = wx.Menu()
one =wx.MenuItem(parser,1,'&Extract Tables with One Heading or Label')
two =wx.MenuItem(parser,1,'&Extract Tables with Two Headings or Labels')
three =wx.MenuItem(parser,1,'&Extract Tables with Three Headings or Labels')
four =wx.MenuItem(parser,1,'&Extract Tables with Four Headings or Labels')
quit = wx.MenuItem(parser, 2, '&Quit\tCtrl+Q')
parser.AppendItem(one)
parser.AppendItem(two)
parser.AppendItem(three)
parser.AppendItem(four)
parser.AppendItem(quit)
menubar.Append(parser, '&Table Parsers')
textRip = wx.Menu()
section =wx.MenuItem(parser,1,'&Extract Text With Section Headings')
textRip.AppendItem(section)
menubar.Append(textRip, '&Text Rippers')
dataHandling = wx.Menu()
deHydrate =wx.MenuItem(dataHandling,1,'&Extract Data from Tables')
dataHandling.AppendItem(deHydrate)
menubar.Append(dataHandling, '&Data Extraction')
self.Bind(wx.EVT_MENU, self.OnQuit, id=2)
this is where I think I am being clever by using a button click to create an instance
of subPanel.
self.Bind(wx.EVT_MENU, self.subPanel(None, -1, 'TEST'),id=1)
self.SetMenuBar(menubar)
self.Centre()
self.Show(True)
def OnQuit(self, event):
self.Close()
class subPanel(wx.Frame):
def __init__(self, parent, id, title):
wx.Frame.__init__(self, parent, id, 'directEDGAR Supplemental Tools', size=(450, 450))
wx.Panel(self,-1)
wx.StaticText(self,-1, "This is where I will describe\n the purpose of these tools",(100,10))
getDirectory = wx.Button(panel, -1, "Get Directory Path", pos=(20,350))
getDirectory.SetDefault()
getTerm1 = wx.Button(panel, -1, "Get Search Term", pos=(20,400))
getTerm1.SetDefault()
#getDirectory.Bind(wx.EVT_BUTTON, getDirectory.OnClick, getDirectory.button)
self.Centre()
self.Show(True)
app = wx.App()
mainPanel(None, -1, '')
app.MainLoop()
I don't know wxWidgets, but based on what I know of Python, I'm guessing that you need to change:
self.Bind(wx.EVT_MENU, self.subPanel(None, -1, 'TEST'),id=1)
to:
self.Bind(wx.EVT_MENU, subPanel(None, -1, 'TEST'),id=1)
"subPanel" is a globally defined class, not a member of "self" (which is a mainPanel).
Edit: Ah, "Bind" seems to bind an action to a function, so you need to give it a function that creates the other class. Try the following. It still doesn't work, but at least it now crashes during the subPanel creation.
self.Bind(wx.EVT_MENU, lambda(x): subPanel(None, -1, 'TEST'),id=1)
You should handle the button click event, and create the panel in your button handler (like you already do with your OnQuit method).
I think the following code basically does what you're after -- creates a new Frame when the button is clicked/menu item is selected.
import wx
class MyFrame(wx.Frame):
def __init__(self, parent, title="My Frame", num=1):
self.num = num
wx.Frame.__init__(self, parent, -1, title)
panel = wx.Panel(self)
button = wx.Button(panel, -1, "New Panel")
button.SetPosition((15, 15))
self.Bind(wx.EVT_BUTTON, self.OnNewPanel, button)
self.Bind(wx.EVT_CLOSE, self.OnCloseWindow)
# Now create a menu
menubar = wx.MenuBar()
self.SetMenuBar(menubar)
# Panel menu
panel_menu = wx.Menu()
# The menu item
menu_newpanel = wx.MenuItem(panel_menu,
wx.NewId(),
"&New Panel",
"Creates a new panel",
wx.ITEM_NORMAL)
panel_menu.AppendItem(menu_newpanel)
menubar.Append(panel_menu, "&Panels")
# Bind the menu event
self.Bind(wx.EVT_MENU, self.OnNewPanel, menu_newpanel)
def OnNewPanel(self, event):
panel = MyFrame(self, "Panel %s" % self.num, self.num+1)
panel.Show()
def OnCloseWindow(self, event):
self.Destroy()
def main():
application = wx.PySimpleApp()
frame = MyFrame(None)
frame.Show()
application.MainLoop()
if __name__ == "__main__":
main()
Edit: Added code to do this from a menu.
You need an event handler in your bind expression
self.bind(wx.EVT_MENU, subPanel(None, -1, 'TEST'),id=1)
needs to be changed to:
self.bind(wx.EVT_MENU, <event handler>, <id of menu item>)
where your event handler responds to the event and instantiates the subpanel:
def OnMenuItem(self, evt): #don't forget the evt
sp = SubPanel(self, wx.ID_ANY, 'TEST')
#I assume you will add it to a sizer
#if you aren't... you should
test_sizer.Add(sp, 1, wx.EXPAND)
#force the frame to refresh the sizers:
self.Layout()
Alternatively, you can instantiate the subpanel in your frame's __init__ and call a subpanel.Hide() after instantiation, and then your menuitem event handler and call a show on the panel subpanel.Show()
Edit: Here is some code that will do what I think that you are asking:
#!usr/bin/env python
import wx
class TestFrame(wx.Frame):
def __init__(self, parent, *args, **kwargs):
wx.Frame.__init__(self, parent, *args, **kwargs)
framesizer = wx.BoxSizer(wx.VERTICAL)
mainpanel = MainPanel(self, wx.ID_ANY)
self.subpanel = SubPanel(self, wx.ID_ANY)
self.subpanel.Hide()
framesizer.Add(mainpanel, 1, wx.EXPAND)
framesizer.Add(self.subpanel, 1, wx.EXPAND)
self.SetSizerAndFit(framesizer)
class MainPanel(wx.Panel):
def __init__(self, parent, *args, **kwargs):
wx.Panel.__init__(self, parent, *args, **kwargs)
panelsizer = wx.BoxSizer(wx.VERTICAL)
but = wx.Button(self, wx.ID_ANY, "Add")
self.Bind(wx.EVT_BUTTON, self.OnAdd, but)
self.panel_shown = False
panelsizer.Add(but, 0)
self.SetSizer(panelsizer)
def OnAdd(self, evt):
if not self.panel_shown:
self.GetParent().subpanel.Show()
self.GetParent().Fit()
self.GetParent().Layout()
self.panel_shown = True
else:
self.GetParent().subpanel.Hide()
self.GetParent().Fit()
self.GetParent().Layout()
self.panel_shown = False
class SubPanel(wx.Panel):
def __init__(self, parent, *args, **kwargs):
wx.Panel.__init__(self, parent, *args, **kwargs)
spsizer = wx.BoxSizer(wx.VERTICAL)
text = wx.StaticText(self, wx.ID_ANY, label='I am a subpanel')
spsizer.Add(text, 1, wx.EXPAND)
self.SetSizer(spsizer)
if __name__ == '__main__':
app = wx.App()
frame = TestFrame(None, wx.ID_ANY, "Test Frame")
frame.Show()
app.MainLoop()

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