Python：deadloop之非模态交互界面（模态循环）（哨兵循环）

deadloop之非模态交互界面（模态循环）（哨兵循环）

通过无限循环，条件退出，实现多模态的交互界面

主要功能1：通过键盘按键g\w\r\b进行界面颜色改变，按q退出

主要功能2：点击界面某处生成输入框，回车使输入框内的文字固定在界面

当等待一个特殊的键入时可用，（以return为例）

while win.getkey() != 'Return':
    pass

下面用到的graphics 图像模块

#我的菜鸡简略版本

from graphics import *

win = GraphWin('Click and Type', 500, 500)

while True:
    keyout = win.checkKey()
    if keyout == 'q':
        break
    elif keyout == 'r':
        win.setBackground('pink')
    elif keyout == 'w':
        win.setBackground('white')
    elif keyout == 'b':
        win.setBackground('lightblue')
    elif keyout == 'g':
        win.setBackground('lightgray')

    pt = win.checkMouse()

    if pt:
        entry = Entry(pt, 5)
        entry.draw(win)

        while True:
            key = win.checkKey()
            if key == 'Return':
                break
            elif key:print(key)

        entry.undraw()
        text = entry.getText()
        Text(pt, text).draw(win)

# 教材版本（不同功能函数定义调用）
# event_loop2.py --- color-changing window
from graphics import *

def handleKey(k, win):
    if k == 'r':
        win.setBackground('pink')
    elif k == 'w':
        win.setBackground('white')
    elif k == 'g':
        win.setBackground('lightgray')
    elif k == 'b':
        win.setBackground('lightblue')

def handleClick(pt, win):
    #  create an Entry for user to type in
    entry = Entry(pt, 10)
    entry.draw(win)

    # Go modal: loop until user types <Enter> key
    while True:
        key = win.getKey()
        if key == 'Return': break
        else:print(key)

    # undraw the entry and create and draw Text.
    entry.undraw()
    typed = entry.getText()
    Text(pt, typed).draw(win)

    # clear (ignore) ang mouse click that occurred during text entry
    win.checkMouse()

def main():
    win = GraphWin('Click and Type', 500, 500)

    # Event loop: handle presses and mouse clicks until the user
    #   press the 'q' key.
    while True:
        key = win.checkKey()
        if key == 'q':  # loop exit
            break

        if key:
            handleKey(key, win)

        pt = win.checkMouse()
        if pt:
            handleClick(pt, win)

    win.close()

main()

运行效果：