Python基础语法笔记 tkinter的简单使用

语法

物质

动态类型语言,不需要声明类型

数字

类型int float bool

操作 //整除 **幂

字符串

str1 = "Hello python"
str2 = "world"
print(str1 * 3)  # 重复输出
print(str1[1])  # 索引访问
print(str1 + " " + str2)  # 拼接
print(str1[2:4])  # 字符串切片
print(len(str1))  # 长度
#查找与替换
print(str1.find("python"))  # 查找
print(str1.replace("python", "c++"))  # 替换
print(str1.split(" "))  # 以关键字划分
print(str2.upper())  # 大小写lower/upper

数组类

列表和元组

list = [1, 2, 3, 4]  #列表
tuple = (1, 2, 3, 4) #元组
#列表内容可变,元组不可变

列表的操作

arr = ["apple", "banana", "cherry"]
#添加元素
arr.append("orange")  # 在末尾追加元素
arr.insert(1, "pear")  # 在第2个位置插入元素
print(arr)
#删除元素
arr.remove("banana")  # 删除指定元素
del arr[1]  # 删除指定位置的元素
print(arr)
#查找元素
print(arr.index("apple"))  # 查找指定元素的索引位置,没找到抛出异常
print("pear" in arr)  # 判断指定元素是否在数组中

集合

#集合内不允许重复元素
A = {1, 2, 3}
B = {2, 3, 4}
A & B #{2, 3}
A | B #{1, 2, 3, 4}
A - B #{1}
A ^ B #{1, 4}
A <= B #False
length = len(A);

字典

#就是键值对
person = {'name': 'John Doe', 'age': 30, 'gender': 'Male'}
print(person['name']) # John Doe

类与特殊方法

from filecmp import cmp


class Book:
    def __init__(self, title, author, pages):
        self.title = title
        self.author = author
        self.pages = pages

    def __str__(self):
        return f"{self.title} by {self.author}"

    def __repr__(self):  # representation
        return f"Book('{self.title}', '{self.author}', {self.pages})"

    def __len__(self):
        return self.pages

    def __add__(self, other):
        return self.pages + other.pages

    def __eq__(self, other):
        return (
            self.title == other.title
            and self.author == other.author
            and self.pages == other.pages
        )


book1 = Book("The Great Gatsby", "F. Scott Fitzgerald", 180)
book2 = Book("To Kill a Mockingbird", "Harper Lee", 198)

print(book1)
# Output: The Great Gatsby by F. Scott Fitzgerald

print(repr(book1))
# Output: Book('The Great Gatsby', 'F. Scott Fitzgerald', 180)

print(book1 + book2)
# Output: 378

print(book1 == book2)
# Output: False

print(book1 == Book("The Great Gatsby", "F. Scott Fitzgerald", 180))
# Output: True

运动

输入输出

输入

name = input("Please enter your name: ")
#输入
n = int(input())#默认输入尾string类型,可以格式化为int,float
print("Hello, " + name)
sets = set(input('|').split()[1:])#获取以|分割后的第二个至行尾的所有单词

nums = input().split()  # 将字符串分割成多个子串
arr = [float(x) for x in nums]  # 将每个子串转换成浮点数类型，得到一个浮点数列表

输出

# 普通输出
print("Hello, World!")
# python的每句print自动换行,不需要换行则加end
print("Hello, World!", end="")
print(" Welcome to Python.")
# 格式化输出
name = "John"
age = 30
## 三种格式化
print("My name is {} and I am {} years old.".format(name, age))
print(f"My name is {name} and I am {age} years old.") #Python 3.6引入
print("My name is %s and I am %d years old." % (name, age))
## 控制小数位数
value = 3.1415926
print("The value of pi is {:.2f}.".format(value))
##占位长度以及左右对齐
print("My name is {:10} and I am {:<10} years old.".format(name, age))
'''输出如下
Hello, World!
Hello, World! Welcome to Python.
My name is John and I am 30 years old.
My name is John and I am 30 years old.
My name is John and I am 30 years old.
The value of pi is 3.14.
My name is John       and I am 30         years old.
'''

逻辑

1. 比较运算,位运算,赋值运算
2. 逻辑运算：与（and）、或（or）和非（not）
3. 成员运算：在序列（字符串、列表、元组）中检查成员（in 和 not in）
4. 身份运算：检查对象是否是同一个（is 和 is not）

控制语句

for i in range(1, 11):
    if i == 5:
        continue
    print(i)
while True:
    user_input = input("请输入任意字符，输入'q'退出: ")
    if user_input == "q":
        break
    print("你输入的字符是: " + user_input)

单条件 类似于 c语言中的? :

x = 10
y = 20
max_value = x if x > y else y
print(max_value) # 输出结果为20

函数

#定义计算平方的函数
def square(x):
    result = x * x
    return result

列表推导式

square_list = [x**2 for x in range(1, 11)]
print(square_list)
#输出如下[1, 4, 9, 16, 25, 36, 49, 64, 81, 100]

#统计数组中的重复数字个数
len(set([x for x in nums if x != 0]))

#每个单词的第一个数字
words = ["apple", "banana", "cherry", "dragonfruit", "elderberry", "fig"]
first_letters = {word[0] for word in words}
print(first_letters)
#输出如下{'c', 'b', 'a', 'e', 'd', 'f'}

应用

打包

先安装pip install pyinstaller

然后pyinstaller --onefile -w D:\code\scripts\py\learn.py

打包并包含库文件,并隐藏命令行窗口

虚拟环境

使用虚拟环境打包可以让可执行文件更小

使用python3.6以上自带的venv,在vscode的PS终端中执行以下命令

#创建虚拟环境
python -m venv test_env
#激活环境
.\test_env\Scripts\Activate.ps1#执行不了就先Set-ExecutionPolicy RemoteSigned
#然后安装包
pip list#查看
pip install pandas#安装
#退出环境
deactivate

Tkinter

界面

基于tkinter,需要先安装库pip install ttkbootstrap tkinter

布局

三种布局方式:
pack相对用户来说不需要做过多操作就可以自动元素排列，适合于整体布局
grid布局相对来说有板有眼，适合那种规规矩矩的布局
place布局适合那种对细节要求严丝合缝的场合

pack

widgets.pack(pack_options) 这个是函数原型，pack_options有三个常用属性，分别是expand ，fill，side这三个属性

expand 是否扩展，当它设置为true的时候，它会沾满父组件的空间，当然，这是在其它同级元素布局剩下之后的空间。
fill 是填充的意思，它可以指定填充的方向，比如我们想要一个button或者label占满一行，我们可以就可以设置fill = tk.X （其中tk是tkiner的简写，import tkinter as tk）
side是一侧的意思，比如我们要让两个button并排显示可以一个设置side=tk.LEFT，一个设置为tk.RIGHT
pdx,pdy是用来设置距离左右上下的位置的，有了他们，我们就可以灵活设置组件的布局了

示例

import tkinter as tk
root = tk.Tk()
root.title(u"pack布局演示")
tk.Button(root, text="side:top").pack(side='top')
tk.Button(root, text="side:bottom").pack(side='bottom')
tk.Button(root, text="side:left").pack(side='left')
tk.Button(root, text="side:right").pack(side='right')
root.mainloop()

grid

grid有4个可选参数，分别是row,rowspan,column,columnspan，sticky

row指的是排在第一行
rowspan指的是占有多少行
column指的是排在第几列
columnspan指的是占有几列
sticky粘性，指的就是对齐固定方式，有nswe4个方位，分别是上北下南左西右东（n=nouth,s=south,e=east,w=west）

示例

import tkinter as tk
root = tk.Tk()
root.title(u"grid布局演示")
for row in range(3):
    for col in range(4):
        text_ = "row=%d, col=%d" % (row, col)
        tk.Button(root, text=text_).grid(row=row, column=col)
root.mainloop()

place

坐标布局使用place进行元素的位置放置，它有x,y两参数，可以用来指定距离父组件的左上角的横坐标距离和纵坐标距离。

实战

一个利用tkinter实现逐差法,和作散点图

另外还有更换背景功能

import tkinter as tk
from ttkbootstrap import Style
from tkinter import messagebox
from PIL import Image, ImageTk
import matplotlib.pyplot as plt
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg
import os


data = []


def background(window):
    def resize_image():
        new_width = window.winfo_width()
        new_height = window.winfo_height()
        resized_image = original_image.resize((new_width, new_height))
        new_photo = ImageTk.PhotoImage(resized_image)
        background_label.config(image=new_photo)
        background_label.image = new_photo

    current_path = os.path.realpath(__file__)
    current_directory = os.path.dirname(current_path)
    jpg_path = os.path.join(current_directory, "background.jpg")
    original_image = Image.open(jpg_path)
    photo = ImageTk.PhotoImage(original_image)

    background_label = tk.Label(window, image=photo)
    background_label.place(x=0, y=0, relwidth=1, relheight=1)  # 设置Label的相对大小，使其铺满整个窗口

    window.bind("<Configure>", lambda event: resize_image())


def create_input(window, text, data_var):
    data_frame = tk.Frame(window)
    data_label = tk.Label(data_frame, text=text, font=("Arial", 16), width=15)
    data_label.pack(side=tk.LEFT)
    data_entry = tk.Entry(data_frame, textvariable=data_var)
    data_entry.pack(side=tk.LEFT)
    # return data_frame
    data_frame.pack()


def create_window(text, command):
    tk.Button(
        root, text=text, font=("Arial", 30), width=10, height=2, command=command
    ).pack(pady=10)


def full_window(window):
    w = window.winfo_screenwidth()
    h = window.winfo_screenheight()
    window.geometry("%dx%d" % (w, h))


def create_button(window, text, command):
    tk.Button(
        window, text=text, font=("Arial", 16), width=12, height=1, command=command
    ).pack(pady=10)


def create_table(num, table_frame):
    try:
        global data
        data.clear()

        rows = (num + 9) // 10
        cols = min(num, 10)
        for i in range(rows):
            row = []
            if i == rows - 1 and num % 10 != 0:
                cols = num % 10
            for j in range(cols):
                entry = tk.Entry(table_frame, width=6)
                entry.grid(row=i, column=j)
                row.append(entry)
            data.append(row)

    except ValueError:
        messagebox.showerror("错误", "请输入有效的数据个数！")


def center_window(root, width, height):
    screenwidth = root.winfo_screenwidth()  # 获取显示屏宽度
    screenheight = root.winfo_screenheight()  # 获取显示屏高度
    size = "%dx%d+%d+%d" % (
        width,
        height,
        (screenwidth - width) / 2,
        (screenheight - height) / 2,
    )  # 设置窗口居中参数
    root.geometry(size)


def sub_window_style(window):
    # window.title()
    center_window(window, 800, 600)
    background(window)


def diff():
    def calc():
        try:
            global data
            nums = [float(entry.get()) for row in data for entry in row]
            n2 = len(nums)
            n = n2 // 2
            print(n)
            result = sum([nums[i + n] - nums[i] for i in range(n)]) / (n * n)
            result_text.insert(tk.END, f"逐差法结果为：{result}\n")
        except ValueError:
            messagebox.showerror("错误", "表格中存在非数字的输入！")

    window = tk.Toplevel(root)
    sub_window_style(window)

    data_N = tk.IntVar()
    create_input(window, "数据个数：", data_N)

    table_frame = tk.Frame(window)
    create_button(
        window, text="生成表格", command=lambda: create_table(data_N.get(), table_frame)
    )

    table_frame.pack()
    create_button(window, text="计算", command=calc)

    result_text = tk.Text(window, height=30, width=45)
    result_text.pack()




def plot():
    def gen_table(num, table_frame):
        global data
        data.clear()

        rows = 2
        cols = num

        for i in range(rows):
            row = []
            for j in range(cols):
                entry = tk.Entry(table_frame, width=6)
                entry.grid(row=i, column=j)
                row.append(entry)
            data.append(row)

    def calc():
        try:
            global data
            x = [float(entry.get()) for entry in data[0]]
            y = [float(entry.get()) for entry in data[1]]

            # 生成折线图
            plt.figure(figsize=(6, 4))
            plt.plot(x, y, marker="o", label="Data")
            plt.xlabel("X")
            plt.ylabel("Y")
            # plt.title("折线图")
            plt.legend()

            # 在tkinter窗口中显示折线图
            canvas = FigureCanvasTkAgg(plt.gcf(), master=window)
            canvas_widget = canvas.get_tk_widget()
            canvas_widget.pack(side=tk.BOTTOM, fill=tk.BOTH, expand=True)

        except ValueError:
            messagebox.showerror("错误", "表格中存在非数字的输入！")

    window = tk.Toplevel(root)
    sub_window_style(window)

    # 创建输入
    data_N = tk.IntVar()
    create_input(window, "数据个数: ", data_N)

    table_frame = tk.Frame(window)

    create_button(window, "生成表格", lambda: gen_table(data_N.get(), table_frame))

    table_frame.pack()
    create_button(window, "生成折线图", lambda: calc())



style = Style(theme="darkly")
root = style.master
root.title("主窗口")
full_window(root)

background(root)

create_window("逐差法", lambda: diff())
create_window("作图", lambda: plot())
root.mainloop()