Tkinter界面实操

常用opencv-python进行图像处理，有时需要图形用户界面，写个Demo以备不时之需。

Tkinter

1. 导入库

由于 Tkinter 是内置到 python 的安装包中、只要安装好 Python 之后就能 import Tkinter。

 import tkinter 

2. 窗口

root=Tk()                   #生成主窗口
root.geometry(‘250x250’)    #改变窗体大小（‘宽x高’），注意是x不是*
root.geometry(’+450+450’)   #改变窗体位置（‘+横坐标+纵坐标’）
root.title(‘标题名’)         #修改框体的名字
root.mainloop()             #显示主窗口
root.resizable(0, 0)        #将窗口大小设置为不可变
root.resizable(False, False)#将窗口大小设置为不可变

3. 组件

常用的组件有Label，Button，Checkbutton，Radiobutton，Frame，Entry，Listbox，Scrollbar等。

config用来配置tkinter中控件和字体的样式，比如颜色、大小等。给Button的command属性赋值可以指定按钮按下时执行函数中的代码的功能。比如：

import tkinter as tk

def btnHelloClicked():
    labelHello.config(text="Hello Tkinter!")

root = tk.Tk()
root.title("Button Test")
labelHello = tk.Label(root, text="Press the button...", height=5, width=20, fg="blue")
labelHello.pack()
btn = tk.Button(root, text="Hello", command=btnHelloClicked)
btn.pack()
root.mainloop()

4. 布局

管理组件的布局可以使用pack、grid 和 place，其中：

• pack 是按添加顺序排列组件
• grid 是按行/列形式排列组件
• place 则允许程序员指定组件的大小和位置

图片查看器

 代码：

import glob
import tkinter as tk
from tkinter import filedialog
import numpy as np
from PIL import Image, ImageTk
import cv2
from algorithm import tem, detect

window = tk.Tk()
window.geometry("500x500")

path_frame = tk.Frame(window)
path_frame.pack()
filename_var = tk.StringVar()
txt_Path = tk.Entry(path_frame, width=40, textvariable=filename_var)
txt_Path.pack(side=tk.LEFT)

btn_ChoosePic = tk.Button(path_frame, text="单张读图")
btn_ChooseDir = tk.Button(path_frame, text="批量读图")
btn_detect = tk.Button(path_frame, text="识别")
btn_ChoosePic.pack(side=tk.LEFT)
btn_ChooseDir.pack(side=tk.LEFT)
btn_detect.pack(side=tk.LEFT)

pic_label = tk.Label(window, width=400, height=400)
pic_label.pack()

button_frame = tk.Frame(window)
button_frame.pack()
number_var = tk.StringVar()
number_var.set("0 of 0")
index_label = tk.Label(button_frame, textvariable=number_var, bd=1, relief=tk.SUNKEN, anchor=tk.CENTER)
index_label.pack(fill=tk.X)
btn_PrePic = tk.Button(button_frame, text="上一张")
btn_NextPic = tk.Button(button_frame, text="下一张")
btn_PrePic.pack(side=tk.LEFT, anchor=tk.CENTER)
btn_NextPic.pack(side=tk.RIGHT, anchor=tk.CENTER)

index = 0

"""
将图片显示在控件上
"""
def ShowPic():
    global file, filename_var
    picture = Image.open(file)
    filename_var.set(file)
    w, h = picture.size
    picture = resize(w, h, 400, 400, picture)
    picture = ImageTk.PhotoImage(picture)
    pic_label.configure(image=picture, width=400, height=400)
    window.mainloop()


"""
对pil_image对象进行缩放，让它在一个矩形框内，还能保持比例
"""
def resize(w, h, w_box, h_box, pil_image):
    f1 = 1.0 * w_box / w 
    f2 = 1.0 * h_box / h
    factor = min([f1, f2])
    width = int(w * factor)
    height = int(h * factor)
    return pil_image.resize((width, height), Image.ANTIALIAS)


def ChoosePic():
    global file
    file = filedialog.askopenfilename()
    number_var.set("1 of 1")
    ShowPic()


def ChooseDir():
    global files, file
    directory = filedialog.askdirectory()
    files = glob.glob(directory + "/*.jpg")
    file = files[0]
    number_var.set("1 of {}".format(len(files)))
    ShowPic()


def ChangePic(next_no):
    global index, file
    index += next_no
    if index > len(files) - 1:
        index = len(files) - 1
    if index < 0:
        index = 0
    file = files[index]
    number_var.set("{} of {}".format(index + 1, len(files)))
    ShowPic()


def Detect():
    img = cv2.imread(file)
    #  图像处理（略）
    picture = Image.fromarray(cv2.cvtColor(dst, cv2.COLOR_BGR2RGB))
    w, h = picture.size
    w, h = picture.size
    picture = resize(w, h, 400, 400, picture)
    picture = ImageTk.PhotoImage(picture)
    pic_label.configure(image=picture, width=400, height=400)
    window.mainloop()

# 按钮绑定事件
btn_ChoosePic.config(command=ChoosePic)
btn_ChooseDir.config(command=ChooseDir)
btn_detect.config(command=Detect)
btn_PrePic.config(command=lambda: ChangePic(-1))
btn_NextPic.config(command=lambda: ChangePic(1))
window.mainloop()