tkinter实现带背景图片的登录窗口
实现功能：打开系统登录窗口，输入用户名密码，点击登录后跳转到程序主界面，用户名密码在程序代码里，注意运行时需要自己准备一张背景图片back.png。
主要代码：
self.backCanvas = Canvas(self.frame,width=self.WIDTH,height=self.HEIGHT)
self.backPhoto = ImageTk.PhotoImage(Image.open("back.png").resize((self.WIDTH,self.HEIGHT), Image.Resampling.NEAREST))
self.backCanvas.create_image(self.WIDTH//2,self.HEIGHT//2,image=self.backPhoto)
self.backCanvas.pack()#grid(row=0,column=0,rowspan=3,columnspan=2)思路为先在登录窗口生成一个画布，然后生成背景图片，将图片铺满画布填充，最后将画布载入。
完整代码如下：
# _*_ coding:utf-8 _*_
"""
@ 功能 : 登录窗口跳转
@ author : sxy
@ create date : 2022/12/06
"""
from tkinter import *
from PIL import Image,ImageTk
# -------------------------------------------------------------------------
#程序登录界面
class LoginFrame(object):
def __init__(self, master=None):
self.root = master
self.root.title("XXXX软件登录")
#self.root.geometry('400x250+500+500')
self.WIDTH = 680
self.HEIGHT = 450
self.frame = Frame(self.root)
self.frame.pack()
# Place GUI on the center of screen
self.ws = self.root.winfo_screenwidth()
self.hs = self.root.winfo_screenheight()
x = (self.ws / 2) - (self.WIDTH / 2)
y = (self.hs / 2) - (self.HEIGHT / 2)-10
self.root.geometry('%dx%d+%d+%d' % (self.WIDTH, self.HEIGHT, x, y))
self.backCanvas = Canvas(self.frame,width=self.WIDTH,height=self.HEIGHT)
self.backPhoto = ImageTk.PhotoImage(Image.open("back.png").resize((self.WIDTH,self.HEIGHT),
Image.Resampling.NEAREST))
self.backCanvas.create_image(self.WIDTH//2,self.HEIGHT//2,image=self.backPhoto)
self.backCanvas.pack()#grid(row=0,column=0,rowspan=3,columnspan=2)
self.lableFrameName=Label(self.frame,text='XXXX软件—系统登录',
font=('微软雅黑', 20))
self.lableFrameName.place(x=200,y=30)
self.labelUserName=Label(self.frame,text='用户名：',font=('微软雅黑', 11))
self.labelUserName.place(x=290,y=140,anchor='e')#grid(row=0,column=0,pady=20)
self.varUserName=StringVar(self.frame,value='')
self.entryUserName=Entry(self.frame,font=('微软雅黑', 12),width=15,textvariable=self.varUserName)
self.entryUserName.place(x=300,y=140,anchor='w')#grid(row=0,column=1,pady=20)
self.entryUserName.focus_set() #获得焦点
self.labelPwd=Label(self.frame,text='密码：',font=('微软雅黑', 11))
#justify=RIGHT,anchor='w',width=80)
self.labelPwd.place(x=290,y=180,anchor='e')#grid(column=0,row=1,pady=10)
self.varPwd=StringVar(self.frame,value='')
self.entryPwd=Entry(self.frame,show='*',font=('微软雅黑', 11),width=15,textvariable=self.varPwd)
self.entryPwd.place(x=300,y=180,anchor='w')#grid(column=1,row=1,pady=10)
self.buttonOk=Button(self.frame,text='登录',font=('微软雅黑', 12),width=8,
command=self.login)
self.buttonOk.place(x=210,y=240)#grid(row=2,column=0,padx=20,pady=20)
self.buttonCancel=Button(self.frame,text='删除',font=('微软雅黑', 12),width=8,
command=self.cancel)
self.buttonCancel.place(x=350,y=240)#grid(row=2,column=1,padx=10,pady=20)
#---------------------------------------------------------------
#登录函数
def login(self):
name=self.entryUserName.get()
pwd=self.entryPwd.get()
if name=='admin' and pwd=='123456':
self.frame.destroy()
#加载主窗口
MainFrame(self.root)
else:
messagebox.showerror('警告',message='用户名或密码错误')
#---------------------------------------------------------------
#取消函数
def cancel(self):
varUserName.set('')
varPwd.set('')
# ----------------------------------------------------------------------
#程序主界面
class MainFrame():
def __init__(self,master=None):
self.root=master
self.root.title('XXXX数据分析软件')
self.WIDTH=1000
self.HEIGHT=760
# Place GUI on the center of screen
self.ws = self.root.winfo_screenwidth()
self.hs = self.root.winfo_screenheight()
x = int((self.ws / 2) - (self.WIDTH / 2))
y = int((self.hs / 2) - (self.HEIGHT / 2))
self.root.geometry('{0:d}x{1:d}+{2:d}+{3:d}'.format(self.WIDTH, self.HEIGHT, x, y))
self.root.resizable(False,False)
Label(self.root, text=' 这是项目主界面窗口',font=('微软雅黑', 16))\
.pack()
#---------------------------------------------------------------------------------------------
if __name__ == "__main__":
root = Tk()
app = LoginFrame(root)
root.mainloop()