Pmw functions

Pmw.alignlabels(widgets,sticky = None)

Adjust the size of the labels of all the widgets to be equal, so that the body of each widget lines up vertically. This assumes that each widget is a megawidget with a label component in column 0 (ie, the labelpos option was set to 'w', 'wn' or 'ws'). If sticky is set to a combination of 'n', 's', 'e' and 'w', the label will be positioned within its cell accordingly. For example to make labels right justified, set sticky to 'e', 'ne' or 'se'.

Pmw.busycallback(command,updateFunction = None)

Create a wrapper function which displays a busy cursor while executing command and return the wrapper. When the wrapper function is called, it first calls Pmw.showbusycursor(), then the command (passing any arguments to it), then Pmw.hidebusycursor(). The return value of command is returned from the wrapper.

If updateFunction is specified, it is called just before the call to Pmw.hidebusycursor(). This is intended to be the Tkinter update() method, in which case it will clear any events that may have occurred while command was executing. An example of this usage is in the ShowBusy demonstration: run the demonstration, click on the entry widget then click on the button and type some characters while the busy cursor is displayed. No characters should appear in the entry widget.

Note that the Tkinter update() method should only be called when it is known that it can be safely called. One case where a problem has been found is when a filehandler has been created (on a non-blocking Oracle database connection), but the filehandler does not read from the connection. The connection is read (by a call to the Oracle fetch function ofen) in a loop which also contains a call to _tkinter.dooneevent(). If update() is called from dooneevent() and there is data to be read on the connection, then the filehandler will be called continuously, thus hanging the application.

Pmw.clearbusycursor()

Unconditionally remove the event block and busy cursor from all windows. This undoes all outstanding calls to Pmw.showbusycursor().

Pmw.displayerror(text)

This is a general purpose method for displaying background errors to the user. The errors would normally be programming errors and may be caused by errors in Tk callbacks or functions called by other asynchronous events.

If the global error report file (set by calling Pmw.reporterrorstofile()) is None, the error message `text` is written to standard error and also shown in a text window. If displayerror is called while previous error messages are being displayed, the window is raised and the new error is queued. The queued errors may be viewed by the user or ignored by dismissing the window.

If the global error report file is not None, `text` is written to the file. file may be any object with a write() method, such as sys.stderr.

Pmw.drawarrow(canvas,color,direction,tag,baseOffset = 0.25,edgeOffset = 0.15)

Draw a triangle in the Tkinter.Canvas canvas in the given color. The value of direction may be 'up', 'down', 'left' or 'right' and specifies which direction the arrow should point. The values of baseOffset and edgeOffset specify how far from the edges of the canvas the points of the triangles are as a fraction of the size of the canvas.

Pmw.forwardmethods(fromClass,toClass,toPart,exclude = ())

Forward methods from one class to another.

This function adds methods to the class fromClass. The names of the methods added are the names of the methods of the class toClass (and its base classes) except those which are already defined by fromClass or are found in the exclude list. Special methods with one or more leading or trailing underscores are also excluded.

When one of the added methods is called, the method of the same name is called on an instance defined by toPart and the return value passed back. If toPart is a string, then it specifies the name of an attribute (not a component) of the fromClass object. The class of this attribute should be toClass. If toPart is not a string, it must be a function taking a fromClass object and returning a toClass object.

This function must be called outside of and after the definition of fromClass.

For example:

class MyClass:
    def __init__(self):
        ...
        self.__target = TargetClass()
        ...

    def foo(self):
        pass

    def findtarget(self):
        return self.__target

Pmw.forwardmethods(MyClass, TargetClass, '__target',
    ['dangerous1', 'dangerous2'])

# ...or...

Pmw.forwardmethods(MyClass, TargetClass,
    MyClass.findtarget, ['dangerous1', 'dangerous2'])

In both cases, all TargetClass methods will be forwarded from MyClass except for dangerous1, dangerous2, special methods like __str__, and pre-existing methods like foo.

Pmw.grabstacktopwindow()

Return the window at the top of the grab stack (the window currently with the grab) or None if the grab stack is empty (no window has the grab). See also pushgrab().

Pmw.hidebusycursor(forceFocusRestore = 0)

Undo one call to Pmw.showbusycursor(). If there are no outstanding calls to Pmw.showbusycursor(), remove the event block and busy cursor.

If the focus window has not been changed since the corresponding call to Pmw.showbusycursor(), or if forceFocusRestore is true, then the focus is restored to that saved by Pmw.showbusycursor().

Pmw.initialise(root = None,size = None,fontScheme = None,useTkOptionDb = 0,noBltBusy = 0,disableKeyboardWhileBusy = None)

Initialise Pmw. This performs several functions:

It is not absolutely necessary to call this function to be able to use Pmw. However, some functionality will be lost. Most importantly, Pmw megawidgets will not be notified when their hull widget is destroyed. This may prevent the megawidget from cleaning up timers which will try to access the widget, hence causing a background error to occur.

Pmw.installedversions(alpha = 0)

If alpha is false, return the list of base versions of Pmw that are currently installed and available for use. If alpha is true, return the list of alpha versions.

Pmw.popgrab(window)

Remove window from the grab stack. If there are not more windows in the grab stack, release the grab. Otherwise set the grab and the focus to the next window in the grab stack. See also pushgrab().

Pmw.pushgrab(grabWindow,globalMode,deactivateFunction)

The grab functions (pushgrab(), popgrab(), releasegrabs() and grabstacktopwindow()) are an interface to the Tk grab command which implements simple pointer and keyboard grabs. When a grab is set for a particular window, Tk restricts all pointer events to the grab window and its descendants in Tk's window hierarchy. The functions are used by the activate() and deactivate() methods to implement modal dialogs.

Pmw maintains a stack of grabbed windows, where the window on the top of the stack is the window currently with the grab. The grab stack allows nested modal dialogs, where one modal dialog can be activated while another modal dialog is activated. When the second dialog is deactivated, the first dialog becomes active again.

Use pushgrab() to add grabWindow to the grab stack. This releases the grab by the window currently on top of the stack (if there is one) and gives the grab and focus to the grabWindow. If globalMode is true, perform a global grab, otherwise perform a local grab. The value of deactivateFunction specifies a function to call (usually grabWindow.deactivate) if popgrab() is called (usually from a deactivate() method) on a window which is not at the top of the stack (that is, does not have the grab or focus). For example, if a modal dialog is deleted by the window manager or deactivated by a timer. In this case, all dialogs above and including this one are deactivated, starting at the top of the stack.

For more information, see the Tk grab manual page.

Pmw.releasegrabs()

Release grab and clear the grab stack. This should normally not be used, use popgrab() instead. See also pushgrab().

Pmw.reporterrorstofile(file = None)

Sets the global error report file, which is initially None. See Pmw.displayerror()

Pmw.setalphaversions(*alpha_versions)

Set the list of alpha versions of Pmw to use for this session to the arguments. When searching for Pmw classes and functions, these alpha versions will be searched, in the order given, before the base version. This must be called before any other Pmw class or function, except functions setting or querying versions.

Pmw.setbusycursorattributes(window,**kw)

Use the keyword arguments to set attributes controlling the effect on window (which must be a Tkinter.Toplevel) of future calls to Pmw.showbusycursor(). The attributes are:

exclude
a boolean value which specifies whether the window will be affected by calls to Pmw.showbusycursor(). If a window is excluded, then the cursor will not be changed to a busy cursor and events will still be delivered to the window. By default, windows are affected by calls to Pmw.showbusycursor().

cursorName
the name of the cursor to use when displaying the busy cursor. If None, then the default cursor is used.

Pmw.setgeometryanddeiconify(window,geom)

Deiconify and raise the toplevel window and set its position and size according to geom. This overcomes some problems with the window flashing under X and correctly positions the window under NT (caused by Tk bugs).

Pmw.setversion(version)

Set the version of Pmw to use for this session to version. If Pmw.setversion() is not called, the latest installed version of Pmw will be used. This must be called before any other Pmw class or function, except functions setting or querying versions.

Pmw.showbusycursor()

Block events to and display a busy cursor over all windows in this application that are in the state 'normal' or 'iconic', except those windows whose exclude busycursor attribute has been set to true by a call to Pmw.setbusycursorattributes().

If a window and its contents have just been created, update_idletasks() may have to be called before Pmw.showbusycursor() so that the window is mapped to the screen. Windows created or deiconified after calling Pmw.showbusycursor() will not be blocked.

To unblock events and remove the busy cursor, use Pmw.hidebusycursor(). Nested calls to Pmw.showbusycursor() may be made. In this case, a matching number of calls to Pmw.hidebusycursor() must be made before the event block and busy cursor are removed.

If the BLT extension to Tk is not present, this function has no effect other than to save the value of the current focus window, to be later restored by Pmw.hidebusycursor().

Pmw.tracetk(root = None,on = 1,withStackTrace = 0,file = None)

Print debugging trace of calls to, and callbacks from, the Tk interpreter associated with the root window . If root is None, use the Tkinter default root. If on is true, start tracing, otherwise stop tracing. If withStackTrace is true, print a python function call stacktrace after the trace for each call to Tk. If file is None, print to standard error, otherwise print to the file given by file.

For each call to Tk, the Tk command and its options are printed as a python tuple, followed by the return value of the command (if not the empty string). For example:

python executed:
  button = Tkinter.Button()
  button.configure(text = 'Hi')

tracetk output:
  CALL  TK> 1:  ('button', '.3662448') -> '.3662448'
  CALL  TK> 1:  ('.3662448', 'configure', '-text', 'Hi')

Some calls from python to Tk (such as update, tkwait, invoke, etc) result in the execution of callbacks from Tk to python. These python callbacks can then recursively call into Tk. When displayed by tracetk(), these recursive calls are indented proportionally to the depth of recursion. The depth is also printed as a leading number. The return value of a call to Tk which generated recursive calls is printed on a separate line at the end of the recursion. For example:

python executed:
  def callback():
      button.configure(text = 'Bye')
      return 'Got me!'
  button = Tkinter.Button()
  button.configure(command = callback)
  button.invoke()
tracetk output:
  CALL  TK> 1:  ('button', '.3587144') -> '.3587144'
  CALL  TK> 1:  ('.3587144', 'configure', '-command', '3638368callback')
  CALL  TK> 1:  ('.3587144', 'invoke')
  CALLBACK> 2:    callback()
  CALL  TK> 2:    ('.3587144', 'configure', '-text', 'Bye')
  CALL RTN> 1:  -> 'Got me!'

Pmw.initialise() must be called before tracetk() so that hooks are put into the Tkinter CallWrapper class to trace callbacks from Tk to python and also to handle recursive calls correctly.

Pmw.version(alpha = 0)

If alpha is false, return the base version of Pmw being used for this session. If Pmw.setversion() has not been called, this will be the latest installed version of Pmw. If alpha is true, return the list of alpha versions of Pmw being used for this session, in search order. If Pmw.setalphaversions() has not been called, this will be the empty list.

Pmw 2.0.0 - 17 Aug 2013 - Home