ttk.Treeview - Can't change row height

Question

I'm using ttkcalendar.py which can be found in this link.

I've adapted it for use in Python 3.3

Basically what i'm trying to do is enter this calendar widget into my Tkinter application, which works fine and there's no problems there.

The problems I wish to overcome are:

1. How do I change the font size of the calendar (Month,Days & Dates) - Completed
2. How do I change the selected date so it goes bold. - Completed
3. How can I change the height of the rows in the treeview as in prevoius attempts font size can be increased but the row height does not increase with font size. - STILL AWAITING HELP

Thanks in advance.

EDIT 1:

Find below the code for the whole program:

import calendar
import tkinter as Tkinter
import tkinter.font as tkFont
from tkinter import ttk                             #Imports ttk Module

def get_calendar(locale, fwday):
    #Instantiate Proper Calendar Class
    if locale is None:
        return calendar.TextCalendar(fwday)
    else:
        return calendar.LocaleTextCalendar(fwday, locale)

class Calendar(ttk.Frame):
    datetime = calendar.datetime.datetime
    timedelta = calendar.datetime.timedelta

    def __init__(self, master=None, **kw):
        """
        WIDGET-SPECIFIC OPTIONS

            locale, firstweekday, year, month, selectbackground,
            selectforeground
        """
        #Remove Custom Options From kw BEFORE Initializating ttk.Frame
        fwday = kw.pop('firstweekday', calendar.MONDAY)
        year = kw.pop('year', self.datetime.now().year)
        month = kw.pop('month', self.datetime.now().month)
        locale = kw.pop('locale', None)
        sel_bg = kw.pop('selectbackground', '#EEEEEE')
        sel_fg = kw.pop('selectforeground', '#B6333B')

        self._date = self.datetime(year, month, 1)
        self._selection = None                          #No Date Selected

        ttk.Frame.__init__(self, master, **kw)

        self._cal = get_calendar(locale, fwday)

        self.__setup_styles()                           #Creates Custom Styles
        self.__place_widgets()                          #Pack/Grid Used Widgets
        self.__config_calendar()                        #Adjust Calendar Columns & Setup Tags
        #Configure a Canvas & Proper Bindings for Selecting Dates
        self.__setup_selection(sel_bg, sel_fg)

        #Store Item ids - Used for Insertion Later On
        self._items = [self._calendar.insert('', 'end', values='')
                            for _ in range(6)]
        #Insert Dates in the Currently Empty Calendar
        self._build_calendar()

        #Set Minimal Size for Widget
        self._calendar.bind('<Map>', self.__minsize)

    def __setitem__(self, item, value):
        if item in ('year', 'month'):
            raise AttributeError("attribute '%s' is not writeable" % item)
        elif item == 'selectbackground':
            self._canvas['background'] = value
        elif item == 'selectforeground':
            self._canvas.itemconfigure(self._canvas.text, item=value)
        else:
            ttk.Frame.__setitem__(self, item, value)

    def __getitem__(self, item):
        if item in ('year', 'month'):
            return getattr(self._date, item)
        elif item == 'selectbackground':
            return self._canvas['background']
        elif item == 'selectforeground':
            return self._canvas.itemcget(self._canvas.text, 'fill')
        else:
            r = ttk.tclobjs_to_py({item: ttk.Frame.__getitem__(self, item)})
            return r[item]

    def __setup_styles(self):
        #CUSTOM ttk Styles
        style = ttk.Style(self.master)
        arrow_layout = lambda dir: (
            [('Button.focus', {'children': [('Button.%sarrow' % dir, None)]})]
        )
        style.layout('L.TButton', arrow_layout('left'))
        style.layout('R.TButton', arrow_layout('right'))

    def __place_widgets(self):
        #Header Frame & Widgets
        hframe = ttk.Frame(self)
        lbtn = ttk.Button(hframe, style='L.TButton', command=self._prev_month)
        rbtn = ttk.Button(hframe, style='R.TButton', command=self._next_month)
        self._header = ttk.Label(hframe, width=15, anchor='center', font='Arial 20')
        #Main Calendar
        self._calendar = ttk.Treeview(show='', selectmode='none', height='6')
        #Pack The Widgets
        hframe.pack(in_=self, side='top', pady=4, anchor='center')
        lbtn.grid(in_=hframe)
        self._header.grid(in_=hframe, column=1, row=0, padx=12)
        rbtn.grid(in_=hframe, column=2, row=0)
        self._calendar.pack(in_=self, expand=1, fill='both', side='bottom')

    def __config_calendar(self):
        cols = self._cal.formatweekheader(3).split()
        self._calendar['columns'] = cols
        self._calendar.tag_configure('header', background='grey90', font='Arial 20')
        self._calendar.insert('', 'end', values=cols, tag=('header', 'dayFont'))
        #Change Font of dayFont TAG
        self._calendar.tag_configure('dayFont', font='Arial 20')
        #Adjust Column Widths
        font = tkFont.Font(size=20)
        maxwidth = max(font.measure(col) for col in cols)
        for col in cols:
            self._calendar.column(col, width=maxwidth, minwidth=maxwidth, anchor='c')

    def __setup_selection(self, sel_bg, sel_fg):
        self._font = tkFont.Font()
        canvas = Tkinter.Canvas(self._calendar, background=sel_bg, borderwidth=0, highlightthickness=0)
        self._canvas = canvas
        canvas.text = canvas.create_text(0, 0, fill=sel_fg, anchor='c')

        canvas.bind('<ButtonPress-1>', lambda evt: canvas.place_forget())
        self._calendar.bind('<Configure>', lambda evt: canvas.place_forget())
        self._calendar.bind('<ButtonPress-1>', self._pressed)

    def __minsize(self, evt):
        width, height = self._calendar.master.geometry().split('x')
        height = height[:height.index('+')]
        self._calendar.master.minsize(width, height)

    def _build_calendar(self):
        year, month = self._date.year, self._date.month

        #Update Header Text (Month, YEAR)
        header = self._cal.formatmonthname(year, month, 0)
        self._header['text'] = header.title()

        #Update Calendar Showing Dates
        cal = self._cal.monthdayscalendar(year, month)

        for indx, item in enumerate(self._items):
            week = cal[indx] if indx < len(cal) else []
            fmt_week = [('%02d' % day) if day else '' for day in week]
            self._calendar.item(item, values=fmt_week, tag='bodyFont')
            self._calendar.tag_configure('bodyFont', font='Arial 10')        


    def _show_selection(self, text, bbox): #SELECTION FONT
        """Configure canvas for a new selection."""
        x, y, width, height = bbox

        textw = self._font.measure(text)

        canvas = self._canvas
        canvas.configure(width=width, height=height)
        canvas.coords(canvas.text, width - textw, height / 2 - 1)
        canvas.itemconfigure(canvas.text, text=text, font='Arial 15 bold')
        canvas.place(in_=self._calendar, x=x, y=y)

    #Callbacks

    def _pressed(self, evt):
        """Clicked somewhere in the calendar."""
        x, y, widget = evt.x, evt.y, evt.widget
        item = widget.identify_row(y)
        column = widget.identify_column(x)

        if not column or not item in self._items:       #Clicked in the Weekdays Row or Just Outside The Columns
            return

        item_values = widget.item(item)['values']
        if not len(item_values):                        #Row is Empty For This Month
            return

        text = item_values[int(column[1]) - 1]
        if not text:                                    #Date is Empty
            return

        bbox = widget.bbox(item, column)
        if not bbox:                                    #Calendar is not Visible Yet
            return

        #Update & Then Show Selection
        text = '%02d' % text
        self._selection = (text, item, column)
        self._show_selection(text, bbox)

    def _prev_month(self):
        """Updated calendar to show the previous month."""
        self._canvas.place_forget()

        self._date = self._date - self.timedelta(days=1)
        self._date = self.datetime(self._date.year, self._date.month, 1)
        #Reconstruct Calendar
        self._build_calendar()

    def _next_month(self):
        """Update calendar to show the next month."""
        self._canvas.place_forget()

        year, month = self._date.year, self._date.month
        self._date = self._date + self.timedelta(
            days=calendar.monthrange(year, month)[1] + 1)
        self._date = self.datetime(self._date.year, self._date.month, 1)

        self._build_calendar() 

    #Properties
    #-----------------------------------------------------

    @property
    def selection(self):
        """Return a datetime representing the current selected date."""
        if not self._selection:
            return None

        year, month = self._date.year, self._date.month
        return self.datetime(year, month, int(self._selection[0]))

#----------------------------------

EDIT 2:

How can I change the relief of the Treeview?

Answer 1

I found that the Tkinter Font object has a metrics() method, that gives its height as "linespace". That allows the row height to be scaled dynamically:

try:
    from tkinter.font import Font
    from tkinter.ttk import Style, Treeview
    from tkinter import *         
except:
    from tkFont import Font
    from ttk import Style, Treeview
    from Tkinter import *

font=Font(family='Arial', size=20)
font.metrics()
#output: {'ascent': 31, 'descent': 7, 'linespace': 38, 'fixed': 0}

With that, you can get the font height with:

font.metrics()['linespace']
#output: 38

Then use it to set the rowheight in your Treeview widget:

fontheight=font.metrics()['linespace']

style=Style()
style.configure('Calendar.Treeview', font=font, rowheight=fontheight)   

tree=Treeview(style='Calendar.Treeview')

Changing the font object parameters comfortably updates the Treeview widget, but the rowheight doesn't get updated, and needs to be redone. So for example, scaling the font size with a keyboard shortcut may look like this:

def scaleup(event):
    font['size']+=1
    style.configure('Calendar.Treeview', rowheight=font.metrics()['linespace'])

def scaledown(event):
    font['size']-=1
    style.configure('Calendar.Treeview', rowheight=font.metrics()['linespace'])

tree.bind('<Control-equal>', scaleup)
tree.bind('<Control-minus>', scaledown)

I actually wanted to do the same with Control-MouseWheel, but didn't figure out the behavior yet (Would be glad to hear how that works).

Hope this comes handy.