cpython/Demo/tix/samples/Control.py

# -*-mode: python; fill-column: 75; tab-width: 8; coding: iso-latin-1-unix -*-
#
# $Id$
#
# Tix Demostration Program
#
# This sample program is structured in such a way so that it can be
# executed from the Tix demo program "tixwidgets.py": it must have a
# procedure called "RunSample". It should also have the "if" statment
# at the end of this file so that it can be run as a standalone
# program.

# This file demonstrates the use of the tixControl widget -- it is an
# entry widget with up/down arrow buttons. You can use the arrow buttons
# to adjust the value inside the entry widget.
#
# This example program uses three Control widgets. One lets you select
# integer values; one lets you select floating point values and the last
# one lets you select a few names.

import tkinter.tix

TCL_ALL_EVENTS          = 0

def RunSample (root):
    control = DemoControl(root)
    control.mainloop()
    control.destroy()

class DemoControl:
    def __init__(self, w):
        self.root = w
        self.exit = -1

        global demo_maker, demo_thrust, demo_num_engines

        demo_maker = tkinter.tix.StringVar()
        demo_thrust = tkinter.tix.DoubleVar()
        demo_num_engines = tkinter.tix.IntVar()
        demo_maker.set('P&W')
        demo_thrust.set(20000.0)
        demo_num_engines.set(2)

        top = tkinter.tix.Frame(w, bd=1, relief=tkinter.tix.RAISED)

        # $w.top.a allows only integer values
        #
        # [Hint] The -options switch sets the options of the subwidgets.
        # [Hint] We set the label.width subwidget option of the Controls to
        #        be 16 so that their labels appear to be aligned.
        #
        a = tkinter.tix.Control(top, label='Number of Engines: ', integer=1,
                        variable=demo_num_engines, min=1, max=4,
                        options='entry.width 10 label.width 20 label.anchor e')

        b = tkinter.tix.Control(top, label='Thrust: ', integer=0,
                        min='10000.0', max='60000.0', step=500,
                        variable=demo_thrust,
                        options='entry.width 10 label.width 20 label.anchor e')

        c = tkinter.tix.Control(top, label='Engine Maker: ', value='P&W',
                        variable=demo_maker,
                        options='entry.width 10 label.width 20 label.anchor e')

        # We can't define these in the init because the widget 'c' doesn't
        # exist yet and we need to reference it
        c['incrcmd'] = lambda w=c: adjust_maker(w, 1)
        c['decrcmd'] = lambda w=c: adjust_maker(w, -1)
        c['validatecmd'] = lambda w=c: validate_maker(w)

        a.pack(side=tkinter.tix.TOP, anchor=tkinter.tix.W)
        b.pack(side=tkinter.tix.TOP, anchor=tkinter.tix.W)
        c.pack(side=tkinter.tix.TOP, anchor=tkinter.tix.W)

        box = tkinter.tix.ButtonBox(w, orientation=tkinter.tix.HORIZONTAL)
        box.add('ok', text='Ok', underline=0, width=6,
                command=self.okcmd)
        box.add('cancel', text='Cancel', underline=0, width=6,
                command=self.quitcmd)
        box.pack(side=tkinter.tix.BOTTOM, fill=tkinter.tix.X)
        top.pack(side=tkinter.tix.TOP, fill=tkinter.tix.BOTH, expand=1)

    def okcmd (self):
        # tixDemo:Status "Selected %d of %s engines each of thrust %d", (demo_num_engines.get(), demo_maker.get(), demo_thrust.get())
        self.quitcmd()

    def quitcmd (self):
        self.exit = 0

    def mainloop(self):
        while self.exit < 0:
            self.root.tk.dooneevent(TCL_ALL_EVENTS)

    def destroy (self):
        self.root.destroy()

maker_list = ['P&W', 'GE', 'Rolls Royce']

def adjust_maker(w, inc):
    i = maker_list.index(demo_maker.get())
    i = i + inc
    if i >= len(maker_list):
        i = 0
    elif i < 0:
        i = len(maker_list) - 1

    # In Tcl/Tix we should return the string maker_list[i]. We can't
    # do that in Tkinter so we set the global variable. (This works).
    demo_maker.set(maker_list[i])

def validate_maker(w):
    try:
        i = maker_list.index(demo_maker.get())
    except ValueError:
        # Works here though. Why ? Beats me.
        return maker_list[0]
    # Works here though. Why ? Beats me.
    return maker_list[i]

if __name__ == '__main__':
    root = tkinter.tix.Tk()
    RunSample(root)