# Pmw functions

Pmw.aboutcontact(value)

  The value passed to this function is used to construct the text displayed by Pmw.AboutDialog megawidgets created subsequently.

Pmw.aboutcopyright(value)

  The value passed to this function is used to construct the text displayed by Pmw.AboutDialog megawidgets created subsequently.

Pmw.aboutversion(value)

  The value passed to this function is used to construct the text displayed by Pmw.AboutDialog megawidgets created subsequently.

Pmw.aligngrouptags(groups)

  This function takes a sequence of Pmw.Groups and adjusts the vertical position of the tags in each group so that they all have the height of the tallest tag. This can be used when groups are positioned side-by-side but the natural height of the tags are different because, for example, different fonts with different sizes are used.

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.alphabeticvalidator(text)

  Validator function for Pmw.EntryField alphabetic standard validator.

Pmw.alphanumericvalidator(text)

  Validator function for Pmw.EntryField alphanumeric standard validator.

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.Tk().tk.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.datestringtojdn(text, fmt = 'ymd', separator = '/')

  Return the Julian Day Number corresponding to the date in text. A Julian Day Number is defined as the number of days since 1 Jan 4713 BC. The date must be specified as three integers separated by the separator character. The integers must be in the order specified by fmt, which must be a combination of 'd', 'm' and 'y' in any order. These give the order of the day, month and year fields. Examples of valid input are:

         'dmy':  31/01/99  31/1/1999  31/1/99
         'mdy':  01/31/99  1/31/1999  1/31/99
         'ymd':  99/01/31  1999/1/31  99/1/31

  If the application's pivot year (default 50) is not None and the year specified in text has only one or two digits, then the year is converted to a four digit year. If it is less than or equal to the pivot year, then it is incremented by the application's century value (default 2000). If it is more than the pivot year then it is incremented by the century value less 100.

  The function `Pmw.setyearpivot()` can be used to change the default values for the application's pivot and century.

Pmw.datevalidator(text, fmt = 'ymd', separator = '/')

  Validator function for Pmw.EntryField date standard validator.

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.hexadecimalvalidator(text)

  Validator function for Pmw.EntryField hexadecimal standard validator.

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:

  - Set up a trap in the tkinter Toplevel constructor so that a list of Toplevels can be maintained. A list of all Toplevel windows needs to be kept so that `Pmw.showbusycursor()` can create busy cursors for them.

  - Set up a trap in the tkinter Toplevel and Frame destructors so that Pmw is notified when these widgets are destroyed. This allows Pmw to destroy megawidgets when their hull widget is destroyed and to prune the list of Toplevels.

  - Modify tkinter's CallWrapper class to improve the display of errors which occur in callbacks. If an error occurs, the new CallWrapper class calls `Pmw.clearbusycursor()` to remove any outstanding busy cursors and calls `Pmw.displayerror()` to display the error.

  - Using the window given by root, set the WM_DELETE_WINDOW root window protocol to destroy the root window. This means that the root window is destroyed if the window manager deletes it. This is only done if the protocol has not been set before the call to `Pmw.initialise()`. This protocol is required if there is a modal dialog displayed and the window manager deletes the root window. Otherwise the application will not exit, even though there are no windows.

  - Set the base font size for the application to size. This is used by `Pmw.logicalfont()` as the default point size for fonts. If this is not given, the default is 14, except under NT where it is 16. These are reasonable default sizes for most screens, but for unusually high or low screen resolutions, an appropriate size should be supplied. Note that Tk's definition of point size, is somewhat idiosyncratic.

  - Set the Tk option database for root according to fontScheme. This changes the default fonts set by Tk. fontScheme may be one of

    None
      Do not change the Tk defaults.

    'pmw1'
      If running under posix (Unix), set the default font to be Helvetica with bold italic menus, italic scales and a special balloon font 6 points smaller than the base font size and with the 'pixel' field set to '12'. For other operating systems (such as NT or Macintosh), simply set the default font to be Helvetica. All fonts are as returned by calls to `Pmw.logicalfont()`.

    'pmw2'
      This is the same as 'pmw1' except that under posix the balloon font is 2 points smaller than the base font size and the 'pixel' field is not set.

    'default'
      This sets the default fonts using the Tk font naming convention, rather than that returned by `Pmw.logicalfont()`. The default font is bold Helvetica. The font for entry widgets is Helvetica. The font for text widgets is Courier The size of all fonts is the application base font size as described above.

  - If root is None, use the tkinter default root window as the root, if it has been created, or create a new Tk root window. The `initialise()` method returns this root.

  - If useTkOptionDb is true, then, when a megawidget is created, the Tk option database will be queried to get the initial values of the options which have not been set in the call to the constructor. The resource name used in the query is the same as the option name and the resource class is the option name with the first letter capitalised. If useTkOptionDb is false, then options for newly created megawidgets will be initialised to default values.

  - If noBltBusy is true, then `Pmw.showbusycursor()` will not display a busy cursor, even if the BLT busy command is present.

  - If disableKeyboardWhileBusy is false, then do not disable keyboard input while displaying the busy cursor. Normally, Pmw ignores keyboard input while displaying the busy cursor by setting the focus for each toplevel window to the Blt busy window. However, under NT, this may cause the toplevel windows to be raised. If this is not acceptable, programs running on NT can request show/hidebusycursor to not ignore keyboard input by setting disableKeyboardWhileBusy to true in `Pmw.initialise()`.

  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.integervalidator(text)

  Validator function for Pmw.EntryField integer standard validator.

Pmw.jdntoymd(jdn, julian = -1, papal = 1)

  Return the year, month and day of the Julian Day Number jdn. If julian is 1, then the date returned will be in the Julian calendar. If julian is 0, then the date returned will be in the modern calendar. If julian is -1, then which calendar to use will be automatically determined by the value of jdn and papal. If papal is true, then the date set by Pope Gregory XIII's decree (4 October 1582) will be used as the last day to use the Julian calendar. If papal is false, then the last day to use the Julian calendar will be according to British-American usage (2 September 1752).

Pmw.logicalfont(name = 'Helvetica', sizeIncr = 0, **kw)

  Return the full name of a Tk font, being a hyphen-separated list of font properties. The logical name of the font is given by name and may be one of 'Helvetica', 'Times', 'Fixed', 'Courier' or 'Typewriter'. Pmw uses this name to define the default values of many of the font properties. The size of the font is the base font size for the application specified in the call to `Pmw.initialise()` increased or decreased by the value of sizeIncr. The other properties of the font may be specified by other named arguments. These may be 'registry', 'foundry', 'family', 'weight', 'slant', 'width', 'style', 'pixel', 'size', 'xres', 'yres', 'spacing', 'avgwidth', 'charset' and 'encoding'.

Pmw.logicalfontnames()

  Return the list of known logical font names that can be given to `Pmw.logicalfont()`.

Pmw.numericvalidator(text)

  Validator function for Pmw.EntryField numeric standard validator.

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.realvalidator(text, separator = '.')

  Validator function for Pmw.EntryField real standard validator.

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.setyearpivot(pivot, century = None)

  Set the pivot year and century for the application's date processing. These values are used in the `datestringtojdn()` method, which is used by Pmw.Counter and Pmw.EntryField and derived classes. The initial values of pivot and century are 50 and 2000 repectively. Return a tuple containing the old values of pivot and century.

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.stringtoreal(text, separator = '.')

  Return the real number represented by text. This is similar to `float()` except that the character representing the decimal point in text is given by separator.

Pmw.timestringtoseconds(text, separator = ':')

  Return the number of seconds corresponding to the time in text. The time must be specified as three integers separated by the separator character and must be in the order hours, minutes and seconds. The first number may be negative, indicating a negative time.

Pmw.timevalidator(text, separator = ':')

  Validator function for Pmw.EntryField time standard validator.

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.ymdtojdn(year, month, day, julian = -1, papal = 1)

  Return the Julian Day Number corresponding to year, month and day. See `jdntoymd()` for description of other arguments)

Pmw 2.1 - 31 Dec 2020 - Home