Zelle图形界面问题

Question

我正在使用Zelle图形库，遇到了替换图形对象（在这个例子中是文本对象）的问题。

这是我的代码：

from Graphics import *

winName = "Window"
win = Window(winName,600,500)
win.setBackground(Color('silver'))


title = Text((300,20),"Zack's Flash Card Maker")
title.draw(win)

p1 = Rectangle((50, 100),(550,400))
p1.setFill(Color("black"))
p1.draw(win)




class FlashCard:
    def __init__(self):
        self.commands = {'addQuestion':self.addQuestion,'startGame':self.startGame}
        self.stack = []
        self.questions = {}
        self.questionAnswered = False
        self.questionsCorrect = 0
        self.questionsIncorrect = 0

    def addQuestion(self):
        question = ' '.join(self.stack)
        self.stack = []
        answer = input(question)
        self.questions[question] = answer

    def startGame(self):
        for question in self.questions:
            if(self.questionAnswered == False):
                answer=input(question)
                questionText = Text((300,150),question)
                questionText.setFill(Color("white"))
                questionText.draw(win)

                if(answer == self.questions[question]):
                    questionAnswer = Text((300,200),answer + " is correct!")
                    questionAnswer.setFill(Color("green"))
                    questionAnswer.draw(win)

                    self.questionsCorrect = self.questionsCorrect + 1


                    continue

                else:
                    questionAnswer = Text((300,200),answer + " is incorrect. Study this one.")
                    questionAnswer.setFill(Color("red"))
                    questionAnswer.draw(win)
                    self.questionsIncorrect = self.questionsIncorrect + 1

                    continue




    def interpret(self,expression):
        for token in expression.split():
            if token in self.commands:
                operator = self.commands[token]
                operator()
            else:
                self.stack.append(token)



i = FlashCard()
i.interpret('What is your dog\'s name? addQuestion')
i.interpret('What is your favorite thing to do? addQuestion')
i.interpret('startGame')

我正在制作一个迷你闪卡程序。它会读取底部的命令，并根据FlashCard类中的字典来执行这些命令。基本上，它是可以工作的：它能正确显示文本对象。但是，文本开始重叠，因为它会重新绘制。我试着把.draw函数放在不同的位置，但要么根本不显示，要么就重叠在一起。

有没有人有什么建议？我希望每次新的闪卡问题时，文本能够被替换。

谢谢！

Answer 1

你可以使用setText这个方法来改变文本内容。

例如：

string = Text(Point(1, 1), 'original string') 
sting.setText('new string')

Answer 2

如果你想让某个东西变得看不见，可以使用一个叫做 undraw() 的命令。我建议你把它放在 continue 语句之前。用法如下：

questionText.undraw()
questionAnswer.undraw()

另外，你也可以使用 del 命令来删除每个 questionText/questionAnswer 的实例，当你用完它们的时候。这样做可能更好，因为你实际上是在释放内存，而不是把数据存着却不去使用。