Python tkinter中label控件动态改变值问题
作者:AshleyXM
这篇文章主要介绍了Python tkinter中label控件动态改变值问题,具有很好的参考价值,希望对大家有所帮助。如有错误或未考虑完全的地方,望不吝赐教
Python tkinter中label控件动态改变值
最近在用tkinter做大作业,因为是第一次接触tkinter,所以会遇到很多问题。
比如这次遇到如何动态改变label控件的显示值,翻看了很多博客,没有看到说的很全面的,但综合起来解决了自己的问题,这里将自己的经验写出来供初学者参考:
from tkinter import * str=StringVar() #StringVar是一个很强大的类,可以辅助控件动态改变值 warning = Label(root, textvariable=str, fg='red', font=('宋体', 10)) # 用于显示警告信息 warning.place(x=30, y=120, anchor='nw') str.set('验证失败!')
这里只是举个简单的例子,来表明动态显示Label控件的值的方法,掌握了这种方法就可以灵活运用到自己的项目中了!
Python tkinter下拉日历控件
自己捣鼓了一个python小程序可视化的集合,需要调用一个下拉日历控件进行日期时间的选择。先百度了一通,找到两篇文章写的很完善了,稍加改动就可以直接调用。
最大的问题是没有时-分-秒选择的功能,其中一位添加了这个功能。。。。。。但是。。。。。。竟然做起来收费的买卖
求人不如求己,既然主体代码都有了,那我们就自己来添加剩下的这点小功能。
import datetime import calendar datetime = calendar.datetime.datetime timedelta = calendar.datetime.timedelta class Calendar: def __init__(s, point = None): s.master = tk.Toplevel() s.master.withdraw() s.master.attributes('-topmost' ,True) fwday = calendar.SUNDAY year = datetime.now().year month = datetime.now().month locale = None sel_bg = '#ecffc4' sel_fg = '#05640e' s._date = datetime(year, month, 1) #每月第一日 s._selection = None #设置为未选中日期 s.G_Frame = ttk.Frame(s.master) s._cal = s.__get_calendar(locale, fwday) s.__setup_styles() # 创建自定义样式 s.__place_widgets() # pack/grid 小部件 s.__config_calendar() # 调整日历列和安装标记 # 配置画布和正确的绑定,以选择日期。 s.__setup_selection(sel_bg, sel_fg) # 存储项ID,用于稍后插入。 s._items = [s._calendar.insert('', 'end', values='') for _ in range(6)] # 在当前空日历中插入日期 s._update() s.G_Frame.pack(expand = 1, fill = 'both') s.master.overrideredirect(1) s.master.update_idletasks() width, height = s.master.winfo_reqwidth(), s.master.winfo_reqheight() s.height=height if point: x, y = point[0], point[1] else: x, y = (s.master.winfo_screenwidth() - width)/2, (s.master.winfo_screenheight() - height)/2 s.master.geometry('%dx%d+%d+%d' % (width, height, x, y)) #窗口位置居中 s.master.after(300, s._main_judge) s.master.deiconify() s.master.focus_set() s.master.wait_window() #这里应该使用wait_window挂起窗口,如果使用mainloop,可能会导致主程序很多错误 def __get_calendar(s, locale, fwday): if locale is None: return calendar.TextCalendar(fwday) else: return calendar.LocaleTextCalendar(fwday, locale) def __setitem__(s, item, value): if item in ('year', 'month'): raise AttributeError("attribute '%s' is not writeable" % item) elif item == 'selectbackground': s._canvas['background'] = value elif item == 'selectforeground': s._canvas.itemconfigure(s._canvas.text, item=value) else: s.G_Frame.__setitem__(s, item, value) def __getitem__(s, item): if item in ('year', 'month'): return getattr(s._date, item) elif item == 'selectbackground': return s._canvas['background'] elif item == 'selectforeground': return s._canvas.itemcget(s._canvas.text, 'fill') else: r = ttk.tclobjs_to_py({item: ttk.Frame.__getitem__(s, item)}) return r[item] def __setup_styles(s): # 自定义TTK风格 style = ttk.Style(s.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(s): # 标头框架及其小部件 Input_judgment_num = s.master.register(s.Input_judgment) # 需要将函数包装一下,必要的 hframe = ttk.Frame(s.G_Frame) gframe = ttk.Frame(s.G_Frame) bframe = ttk.Frame(s.G_Frame) xframe = ttk.Frame(s.G_Frame) hframe.pack(in_=s.G_Frame, side='top', pady=5, anchor='center') gframe.pack(in_=s.G_Frame, fill=tk.X, pady=5) bframe.pack(in_=s.G_Frame, pady=5) xframe.pack(in_=s.G_Frame, side='bottom', pady=5) lbtn = ttk.Button(hframe, style='L.TButton', command=s._prev_month) lbtn.grid(in_=hframe, column=0, row=0, padx=5) rbtn = ttk.Button(hframe, style='R.TButton', command=s._next_month) rbtn.grid(in_=hframe, column=5, row=0, padx=5) #年下拉框 s.CB_year = ttk.Combobox(hframe, width = 5, values = [str(year) for year in range(datetime.now().year, datetime.now().year-11,-1)], validate = 'key', validatecommand = (Input_judgment_num, '%P')) s.CB_year.current(0) s.CB_year.grid(in_=hframe, column=1, row=0) s.CB_year.bind('<KeyPress>', lambda event:s._update(event, True)) s.CB_year.bind("<<ComboboxSelected>>", s._update) tk.Label(hframe, text = '年', justify = 'left').grid(in_=hframe, column=2, row=0, padx=(0,5)) #月下拉框 s.CB_month = ttk.Combobox(hframe, width = 3, values = ['%02d' % month for month in range(1,13)], state = 'readonly') s.CB_month.current(datetime.now().month - 1) s.CB_month.grid(in_=hframe, column=3, row=0) s.CB_month.bind("<<ComboboxSelected>>", s._update) tk.Label(hframe, text = '月', justify = 'left').grid(in_=hframe, column=4, row=0) # 日历部件 s._calendar = ttk.Treeview(gframe, show='', selectmode='none', height=7) s._calendar.pack(expand=1, fill='both', side='bottom', padx=5) #时下拉框 s.CB_hour = ttk.Combobox(bframe, width = 3, values = ['%02d' % hour for hour in range(0,24)], validate = 'key', validatecommand = (Input_judgment_num, '%P')) s.CB_hour.current(0) s.CB_hour.grid(in_=bframe, column=0, row=0) s.CB_hour.bind('<KeyPress>', lambda event:s._update(event, True)) s.CB_hour.bind("<<ComboboxSelected>>", s._update) tk.Label(bframe, text = '时').grid( in_=bframe,column=1, row=0, padx=(0,5)) #分下拉框 s.CB_mins = ttk.Combobox(bframe, width = 3, values = ['%02d' % mins for mins in range(0,60)], validate = 'key', validatecommand = (Input_judgment_num, '%P')) s.CB_mins.current(0) s.CB_mins.grid(in_=bframe, column=2, row=0) s.CB_mins.bind('<KeyPress>', lambda event:s._update(event, True)) s.CB_mins.bind("<<ComboboxSelected>>", s._update) tk.Label(bframe, text = '分').grid(column=3, row=0) #秒下拉框 s.CB_seconds = ttk.Combobox(bframe, width = 3, values = ['%02d' % secds for secds in range(0,60)], validate = 'key', validatecommand = (Input_judgment_num, '%P')) s.CB_seconds.current(0) s.CB_seconds.grid(in_=bframe, column=4, row=0) s.CB_seconds.bind('<KeyPress>', lambda event:s._update(event, True)) s.CB_seconds.bind("<<ComboboxSelected>>", s._update) tk.Label(bframe, text = '秒',justify = 'left').grid(column=5, row=0) ttk.Button(xframe, text = "确 定", width = 6, command = lambda: s._exit(True)).grid(row = 1, column = 0, sticky = 'ns', padx = 20) ttk.Button(xframe, text = "取 消", width = 6, command = s._exit).grid(row = 1, column = 4, sticky = 'ne', padx = 20) tk.Frame(s.G_Frame, bg = '#565656').place(x = 0, y = 0, relx = 0, rely = 0, relwidth = 1, relheigh = 2/200) tk.Frame(s.G_Frame, bg = '#565656').place(x = 0, y = 0, relx = 0, rely = 198/200, relwidth = 1, relheigh = 2/200) tk.Frame(s.G_Frame, bg = '#565656').place(x = 0, y = 0, relx = 0, rely = 0, relwidth = 2/200, relheigh = 1) tk.Frame(s.G_Frame, bg = '#565656').place(x = 0, y = 0, relx = 198/200, rely = 0, relwidth = 2/200, relheigh = 1) def __config_calendar(s): # cols = s._cal.formatweekheader(3).split() cols = ['日','一','二','三','四','五','六'] s._calendar['columns'] = cols s._calendar.tag_configure('header', background='grey90') s._calendar.insert('', 'end', values=cols, tag='header') # 调整其列宽 font = tkFont.Font() maxwidth = max(font.measure(col) for col in cols) for col in cols: s._calendar.column(col, width=maxwidth, minwidth=maxwidth, anchor='center') def __setup_selection(s, sel_bg, sel_fg): def __canvas_forget(evt): canvas.place_forget() s._selection = None s._font = tkFont.Font() s._canvas = canvas = tk.Canvas(s._calendar, background=sel_bg, borderwidth=0, highlightthickness=0) canvas.text = canvas.create_text(0, 0, fill=sel_fg, anchor='w') canvas.bind('<Button-1>', __canvas_forget) s._calendar.bind('<Configure>', __canvas_forget) s._calendar.bind('<Button-1>', s._pressed) def _build_calendar(s): year, month = s._date.year, s._date.month header = s._cal.formatmonthname(year, month, 0) # 更新日历显示的日期 cal = s._cal.monthdayscalendar(year, month) for indx, item in enumerate(s._items): week = cal[indx] if indx < len(cal) else [] fmt_week = [('%02d' % day) if day else '' for day in week] s._calendar.item(item, values=fmt_week) def _show_select(s, text, bbox): x, y, width, height = bbox textw = s._font.measure(text) canvas = s._canvas canvas.configure(width = width, height = height) canvas.coords(canvas.text, (width - textw)/2, height / 2 - 1) canvas.itemconfigure(canvas.text, text=text) canvas.place(in_=s._calendar, x=x, y=y) def _pressed(s, evt = None, item = None, column = None, widget = None): """在日历的某个地方点击。""" if not item: 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 s._items: # 在工作日行中单击或仅在列外单击。 return item_values = widget.item(item)['values'] if not len(item_values): # 这个月的行是空的。 return text = item_values[int(column[1]) - 1] if not text: return bbox = widget.bbox(item, column) if not bbox: # 日历尚不可见 s.master.after(20, lambda : s._pressed(item = item, column = column, widget = widget)) return text = '%02d' % text #日 s._selection = (text, item, column) s._show_select(text, bbox) def _prev_month(s): """更新日历以显示前一个月。""" s._canvas.place_forget() s._selection = None s._date = s._date - timedelta(days=1) s._date = datetime(s._date.year, s._date.month, 1) s.CB_year.set(s._date.year) s.CB_month.set(s._date.month) s._update() def _next_month(s): """更新日历以显示下一个月。""" s._canvas.place_forget() s._selection = None year, month = s._date.year, s._date.month s._date = s._date + timedelta( days=calendar.monthrange(year, month)[1] + 1) s._date = datetime(s._date.year, s._date.month, 1) s.CB_year.set(s._date.year) s.CB_month.set(s._date.month) s._update() def _update(s, event = None, key = None): """刷新界面""" if key and event.keysym != 'Return': return year = int(s.CB_year.get()) month = int(s.CB_month.get()) hour = int(s.CB_hour.get()) mins = int(s.CB_mins.get()) seconds = int(s.CB_seconds.get()) if year == 0 or year > 9999: return s._canvas.place_forget() s._date = datetime(year, month, 1,hour,mins,seconds) s._build_calendar() # 重建日历 if year == datetime.now().year and month == datetime.now().month: day = datetime.now().day for _item, day_list in enumerate(s._cal.monthdayscalendar(year, month)): if day in day_list: item = 'I00' + str(_item + 2) column = '#' + str(day_list.index(day)+1) s.master.after(100, lambda :s._pressed(item = item, column = column, widget = s._calendar)) def _exit(s, confirm = False): if not confirm: s._selection = None s.master.destroy() def _main_judge(s): """判断窗口是否在最顶层""" try: if s.master.focus_displayof() == None or 'toplevel' not in str(s.master.focus_displayof()): s._exit() else: s.master.after(10, s._main_judge) except: s.master.after(10, s._main_judge) def selection(s): """返回表示当前选定日期的日期时间。""" if not s._selection: return None year, month = s._date.year, s._date.month hour=s._date.hour mins = s._date.minute seconds = s._date.second return str(datetime(year, month, int(s._selection[0]),hour,mins,seconds)) def Input_judgment(s, content): """输入判断""" if content.isdigit() or content == "": return True else: return False def getdate(type): #获取选择的日期 for date in [Calendar().selection()]: if date: if(type=='start'): #如果是开始按钮,就赋值给开始日期 start_date.set(date) print elif(type=='end'): end_date.set(date)
调用方法:
# tkinter .button 为例 bt1=tk.Button(frame,width=15,text='开始日期',command=lambda:getdate('start')) bt2=tk.Button(frame,width=15,text='结束日期',command=lambda:getdate('end'))
效果杠杠的,完工。
总结
以上为个人经验,希望能给大家一个参考,也希望大家多多支持脚本之家。