List of known bugs

This is a list of some of the known bugs in Pmw. If you fix any of these, please contribute via the Pmw discussion and announcement mailing list on sourceforge.net.

Under the Enlightenment window manager, if show() is called when a window is already displayed (and is not obscured by other windows), then the application will hang for two seconds. This is either a bug in Tcl/Tk or in Enlightenment. See the comment in the Tk function WaitForConfigureNotify() in the Tk source file tk8.3.2/unix/tkUnixWm.c:
```
 /*
  * One more tricky detail about this procedure.  In some cases the
  * window manager will decide to ignore a configure request (e.g.
  * because it thinks the window is already in the right place).
  * To avoid hanging in this situation, only wait for a few seconds,
  * then give up.
  */
```
On NT, Pmw.MenuBar does not display message bar help for menu items. It seems that Tk menu widgets do not support <Motion> events on MS. This probably is an issue that should be taken up with the Tcl/Tk people. (Reported by Stefan Schone. Pmw.0.7)
Run the CounterDialog.py demo, select the show dialog button and press ok. Now exit the dialog (either with the exit button or the close box). The following error appears:
```
 Menu ID 256 is already in use!Fatal Python Error: Tcl/Tk panic
```
This may be a problem with Mac version of Tk. (Reported by Anthony Wilson.)
Pmw.Balloons bind to widgets and canvas items. This means that bindings made by other users are deleted when the balloon makes its bindings. (For example, the "Delete" canvas item in the Balloon demo overrides that <ButtonPress> binding and so that balloon is not withdrawn when the mouse button is pressed over the item.)

The obvious solution is for Pmw.Balloon to add its bindings with a +. But this would make the unbind and tagunbind methods inconsistent - they would remove all bindings, not just the ones added by the balloon. A better way would be for the balloon to add a bindtag to each widget`s bindtag list - then it would not upset any other bindings and it could be deleted cleanly. (Reported by Joe Saltiel)

 import Tkinter
 import Pmw
 
 def foo(event):
     print '<Enter> event on text'
 
 root = Pmw.initialise()
 balloon = Pmw.Balloon()
 
 canvas = Tkinter.Canvas()
 canvas.pack()
 
 text1 = canvas.create_text(50, 50, text = 'hello
there')
 
 # As is, the balloon does not appear over the text, but foo
 # is called.  Swap the following two lines and the balloon
 # appears but foo will not be called.
 canvas.tag_bind(text1, "<Enter>", foo)
 balloon.tagbind(canvas, text1, 'text 1 help')
 
 root.mainloop()

In Pmw.Balloon, the balloon should not be withdrawn when the pointer leaves a widget or item and it immediatly enters another widget or item with balloon help. Instead, the balloon should be moved and its contents changed immediately.

When a Pmw.Balloon is bound to a canvas item, moving the item becomes very slow. (Reported by Joe Saltiel)

 > Second, after I fixed my ordering problem I noticed, there
 > is a pretty big delay in updating widgets that have balloon
 > messages bound to them.  (For example dragging a box across
 > a screen, the box has a delayed reaction.) I believe this is
 > due to some of the timing functions used in PmwBalloon, I am
 > not sure if there is a way around it.  I set all timers to
 > zero, and still had the problem.

When running Pmw demos under ptui the busy cursor does not appear.
If a combobox has a horizontal scrollbar and it displays its listbox above the entry, then it is misplaced.
Bug in Pmw.PanedWidget: repeat by creating new panes in Demo - existing panes jump to the right 1 or 2 pixels.
Bug in Pmw.PanedWidget: repeat by setting hull_borderwidth to 20 in demo - initial drag jumps to right by about 20 pixels. Also right hand side border is missing. (Fix may be similar to method used in Pmw.ScrolledFrame to give canvas border.)
Fix ButtonRelease events so they do not trigger without a corresponding ButtonPress event.

From Joe Saltiel: I was playing around with a scrolledlistbox and tkFileDialog. When I have the dialog open above the list box and I doubleclick on it, I invoke the selectioncmd of the listbox as well as the tkFileDialog box, should this be happening?

Attached is small sample program you can try. To get the bug to show you must do two things. First, when you open the file dialog box, make sure the item you are going to select if over(above) the scrolledlistbox. Second, you have to double click on that item. If you single click and hit "Open" you do not get the bug. Nor do you get it unless the file you click on is directly over the clickable region of the scrolledlist box.
```
 import Tkinter
 import Pmw
 import tkFileDialog
 import string 
 
 def askOpen():
     file = tkFileDialog.askopenfile(filetypes=[("all files", "*")])  
     print file
 
 def printMe():
     print "Me"
 
 root = Tkinter.Tk()
 Pmw.initialise(root)
 
 frame1 = Tkinter.Frame(root)
 lst = string.split("abc def ghi jkl mno pqr stu vwx yz")
 lstbox = Pmw.ScrolledListBox(frame1, items=lst, selectioncommand=printMe)
 lstbox.grid(row=0, column=0, columnspan=2)
 Tkinter.Button(frame1, text='open', command=askOpen).grid(row=1, column=0)
 Tkinter.Button(frame1, text='exit', command=root.destroy).grid(row=1, column=1)
 frame1.pack()
 
 root.mainloop()
```
Response: I have found where the problem is but I am not sure how to fix it. It appears that the tkFileDialog box closes on a ButtonPress event. The corresponding ButtonRelease event is then sent to whichever widget is under the cursor at the time of the Release. I have reproduced the problem with a Tcl-only script:
```
 listbox .l
 .l insert 0 1 2 3 4
 bind .l <ButtonRelease-1> {puts AAAGGHHH!}

 button .b -text open -command tk_getOpenFile
 pack .l .b
```
If you do a quick Press-Release-Press over the file dialog, it is withdrawn. If you then keep the mouse button down and move the mouse around, you will see that the button and the listbox still respond to it. If you do the final button Release over the listbox, its <ButtonRelease-1> binding is invoked.

I think the correct solution is to modify Pmw to be very careful when to accept ButtonRelease events. It will need to also bind to ButtonPress events and make sure that it gets a Press before it accepts the Release. I'll try to do the change as soon as possible, but the code involved is fairly complex so I it may take a little time.
Investigate bug in Tk8.0: When a dialog pops up over the pointer then the keyboard focus is not set and so <Return> does not invoke default button.
Under both X and NT, the arrows in the timecounter, counter and combobox do not match the scrollbar arrows.

Pmw.Group does not work correctly when the tag is a compound widget. The tag is placed such that the top of the tag is cut off. (Reported by Peter Stoehr.)

 import Tkinter
 import Pmw
 
 root = Tkinter.Tk()
 Pmw.initialise(root, fontScheme = 'pmw1')
 exitButton = Tkinter.Button(root, text = 'Exit', command = root.destroy)
 exitButton.pack(side = 'bottom')
 
 def makeGroup(tagClassName):
     tagClass = eval(tagClassName)
     group = Pmw.Group(
         tag_pyclass = tagClass,
         hull_background = 'red',
         groupchildsite_background = 'blue',
     )
     group.pack(fill = 'both', expand = 1, padx = 6, pady = 6)
     child = Tkinter.Label(group.interior(),
         text = 'Group with tag ' + tagClassName,
         background = 'aliceblue',
     )
     child.pack(padx = 10, pady = 5, expand = 1, fill = 'both')

     return group
 
 grp1 = makeGroup('Pmw.EntryField')
 grp2 = makeGroup('Pmw.ComboBox')
 grp3 = makeGroup('Tkinter.Entry')
 
 root.mainloop()

Also, Pmw.Group does not resize correctly if the simple widget changes size. For example:

 grp3.configure(tag_font = ('Helveltica', '-160'))

Bug(s) in PmwScrolledCanvas. There is a bug in 0.8.1 PmwScrolledCanvas._setRegion. If there are no objects in the canvas, then error occurs on len(region) because region is None. Below is an attempt to fix it. Click on Show, then on Delete. The window then continuously resizes. If the ScrolledCanvas is created with canvasmargin = 0, the problem goes away. (Reported by Anders Henja.)

 import Tkinter
 import Pmw
 
 def _setRegion(self):
     # Attempt to fix PmwScrolledCanvas._setRegion.
     self.setregionTimer = None
 
     region = self._canvas.bbox('all')
     canvasmargin = self['canvasmargin']
     if region is None:
         region = (0, 0, 0, 0)
     region = (region[0] - canvasmargin, region[1] - canvasmargin,
         region[2] + canvasmargin, region[3] + canvasmargin)
     self._canvas.configure(scrollregion = region)
 
 def show():
     canvas.component('canvas').delete('all')
     canvas.create_oval(0, 0, 800, 600, fill = 'red')
     canvas.configure(canvas_width = 600, canvas_height = 450)
     canvas.resizescrollregion()
 
 def delete():
     canvas.component('canvas').delete('all')
     canvas.configure(canvas_width = 0, canvas_height = 0)
     canvas.resizescrollregion()
 
 root=Tkinter.Tk()
 Pmw.initialise(root)
 
 buttonbox=Pmw.ButtonBox()
 buttonbox.pack(fill='x',side='bottom',padx=5,pady=5)
 buttonbox.add('Show',command=show)
 buttonbox.add('Delete',command=delete)
 buttonbox.alignbuttons()
 
 canvas=Pmw.ScrolledCanvas(canvasmargin=2)
 canvas.__class__._setRegion = _setRegion
 canvas.pack(fill='both',side='right',expand=1)
 
 root.mainloop()

Bug in Pmw.Dialog: if defaultbutton is configured before buttons during self.initialiseoptions() (that is if self._constructorKeywords.keys() returns a different order), then setdefault() fails.
Bugs in Tk which affect Pmw.MainMenuBar:
- Extra bindings assigned to a Tkinter.Menu widget using bindtags have no effect. Hence the method used in Pmw.MenuBar for status help (bind_class followed by bindtags) does not work and therefore binding to the menu widget is used instead.
- The 'active' tag for the index() method of Tkinter.Menu always returns None. Hence, in the menu widget motion binding, event.y and the '@' format is used instead, for all menus except the toplevel main menu.
- For the toplevel main menu, event.x must be used for the index() method, but it returns the wrong index. It appears that the Tk widget is assuming vertical layout to calculate distances, rather than horizontal.
- For toplevel main menus, several Tk commands, such as winfo_height(), do not work. This prevents the use of balloon help for Pmw.MainMenuBar.
Bug in Pmw.ComboBox: Tab to combobox arrow, use up/down arrow keys to change selection, hit return, nothing happens, <Shift Tab> to entry window, hit return, combobox changes
- actually, it would be better if you could not tab to the arrow, only the entry field, like the Pmw.Counter.
- the problem is if the entry field is not editable, what to do then?
Bug in TimeCounter: Arrow keys don't work when focus is on entry.
Bug in Pmw.NoteBook: The size of the tab does not change when the text value changes

Bug in Pmw.NoteBook: The name of the tab components has a "-" sign in it, which means that component options can not be used in the configure command. Eg:

 n = Pmw.NoteBook()
 p = n.add('page1')
 n.configure(page1_background = 'red')   # works
 n.configure(page1-tab_background = 'red')   # fail, must do this:
 n.component('page1-tab').configure(background = 'red')   # works

Pmw 2.1 - 31 Dec 2020 - Home