# -*-mode: python; fill-column: 75; tab-width: 8; coding: iso-latin-1-unix -*-## $Id: Control.py 36560 2004-07-18 06:16:08Z tim_one $## 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 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 = Tix.StringVar()        demo_thrust = Tix.DoubleVar()        demo_num_engines = Tix.IntVar()        demo_maker.set('P&W')        demo_thrust.set(20000.0)        demo_num_engines.set(2)         top = Tix.Frame(w, bd=1, relief=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 = 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 = 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 = 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=Tix.TOP, anchor=Tix.W)        b.pack(side=Tix.TOP, anchor=Tix.W)        c.pack(side=Tix.TOP, anchor=Tix.W)         box = Tix.ButtonBox(w, orientation=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=Tix.BOTTOM, fill=Tix.X)        top.pack(side=Tix.TOP, fill=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 = Tix.Tk()    RunSample(root)