学习python的第四天

简易文本编辑器的实现：

import tkinter
import tkinter.colorchooser
import tkinter.messagebox
import tkinter.scrolledtext
import tkinter.simpledialog
import tkinter.filedialog

#创建应用程序窗口
app = tkinter.Tk()
app.title("My Notepad")
app["width"] = 800
app["height"] = 600

#标记当前内容是否发生过改变，是否需要保存
textChanged = tkinter.IntVar(app, value=0)

#当前文件名
filename = ""

#创建菜单
menu = tkinter.Menu(app)

#File子菜单
#tearoff=0表示该子菜单不可以独立
#tearoff=1时，子菜单顶端会有一个虚线
submenu = tkinter.Menu(menu, tearoff=0)


def Open():
    global filename
    #如果内容已改变，先保存
    if textChanged.get():
        yesno = tkinter.messagebox.askyesno(title="Save or not?", message="Do you want to save?")

        if yesno == tkinter.YES:
            Save()
    filename = tkinter.filedialog.askopenfilename(title="Open file", filetypes=[("Text files", "*.txt")])

    if filename:
        txtContent.delete(0.0, tkinter.END)
        with open(filename, "r") as fp:
            txtContent.insert(tkinter.INSERT, "".join(fp.readlines()))
        textChanged.set(0)

#创建Open菜单并绑定菜单时间处理函数
submenu.add_command(label="Open", command=Open)

def Save():
    global filename
    #如果是第一次保存新建文件，则打开“另存为”窗口
    if not filename:
        SaveAs()
    elif textChanged.get():
        with open(filename, "w") as fp:
            fp.write(txtContent.get(0.0, tkinter.END))
        textChanged.set(0)

#创建Save菜单并绑定菜单时间处理函数
submenu.add_command(label="Save", command=Save)


def SaveAs():
    global filename
    #打开“另存为”窗口
    newfilename = tkinter.filedialog.asksaveasfilename(title="Save As", initialdir=r"c:\\", initialfile="new.txt")

    #如果指定了文件名，则保存文件
    if newfilename:
        with open(newfilename, "w") as fp:
            fp.write(txtContent.get(0.0, tkinter.END))
        filename = newfilename
        textChanged.set(0)


submenu.add_command(label="Save as", command=SaveAs)

#添加分割线
submenu.add_separator()

def Close():
    global filename
    Save()
    txtContent.delete(0.0, tkinter.END)
    #置空文件名
    filename = ""


submenu.add_command(label="Close", command=Close)

#将子菜单关联到主菜单
menu.add_cascade(label="File", menu=submenu)

#Edit子菜单
submenu = tkinter.Menu(menu, tearoff=0)

#撤销最后一次操作
def Undo():
    txtContent["Undo"] = True
    try:
        txtContent.edit_undo()
    except Exception as e:
        pass

submenu.add_command(label="Undo", command=Undo)

def Redo():
    txtContent["Redo"] = True
    try:
        txtContent.edit_redo()
    except Exception as e:
        pass

submenu.add_command(label="Redo", command=Redo)

submenu.add_separator()

def Copy():
    txtContent.cilpboard_clear()
    txtContent.clipboard_append(txtContent.selection_get())

submenu.add_command(label="Copy", command=Copy)


def Cut():
    Copy()
    txtContent.delete(tkinter.SEL_FIRST, tkinter.SEL_LAST)

submenu.add_command(label="Cut", command=Cut)

def Paste():
    try:
        txtContent.insert(tkinter.SEL_FIRST, txtContent.clipboard_get())
        txtContent.delete(tkinter.SEL_FIRST, tkinter.SEL_LAST)
        return
    except Exception as e:
        pass
    txtContent.insert(tkinter.INSERT, txtContent.clipboard_get())

submenu.add_command(label="Paste", command=Paste)

submenu.add_separator()


def Search():
    textToSearch = tkinter.simpledialog.askstring(title="Search", prompt="What to search?")

    start = txtContent.search(textToSearch, 0.0, tkinter.END)

    if start:
        tkinter.messagebox.showinfo(title="Found", message="Ok")
    else:
        tkinter.messagebox.showinfo(title="Not found", message="Fail")

submenu.add_command(label="Search", command=Search)

menu.add_cascade(label="Edit", menu=submenu)

#Help菜单
submenu = tkinter.Menu(menu, tearoff=0)
def About():
    tkinter.messagebox.showinfo(title="About", message="writer: HighLights")

submenu.add_command(label="About", command=About)
menu.add_cascade(label="Help", menu=submenu)

#将创建的菜单关联到应用程序窗口
app.config(menu=menu)

#创建文本编辑组件
txtContent = tkinter.scrolledtext.ScrolledText(app, wrap=tkinter.WORD)
txtContent.pack(fill=tkinter.BOTH, expand=tkinter.YES)

def KeyPress(event):
    textChanged.set(1)

txtContent.bind("<KeyPress>", KeyPress)

app.mainloop()