收藏查看收藏按钮按下迅速

Question

我有一个收藏视图，它需要存储哪个按钮被按下。这就好比一个测验，他们有选项A，B，C，D的问题是，它会与此代码选择项：

extension QuestionCell { 
func configure(with model: Question) { 
    factLabel.text = model.fact 
    questionLabel.text = model.question 
    revenueLabel.text = model.revenue 
    let views = answersStack.arrangedSubviews 
    for view in views { 
     view.removeFromSuperview() 
    } 
    for (id, answer) in model.answers { 
     print(index) 
     let answerLabel = UILabel() 
     answerLabel.text = answer 

     answersStack.addArrangedSubview(answerLabel) 

     let answerButton = UIButton() 
     answerButton.tag = index 
     let imageNormal = UIImage(named: "circle_empty") 
     answerButton.setImage(imageNormal, for: .normal) 
     let imageSelected = UIImage(named: "circle_filled") 
     answerButton.setImage(imageSelected, for: .selected) 
     answerButton.setTitleColor(.black, for: .normal) 
     answerButton.addTarget(self, action: #selector(answerPressed(_:)), for: .touchUpInside) 
     answersStack.addArrangedSubview(answerButton) 

    } 
} 

不过，如果你刷几次，然后回来这个问题的形象会再次变成白色。我该如何解决这个问题。我还附上了屏幕的外观。

This is how it looks like

〜感谢

Answer 1

你可以一个答案类这样的解决这个问题。如果你是新的班，我要指出，你不会想写内其他的类定义的代码（如您的ViewController类）。

class Answer{ 
    var wasSelected = false 
    var text : String 

    init(text : String) { 
     self.text = text 
    } 

} 
class ButtonWithAnswer : UIButton{ 
    var answer : Answer? 
} 

但现在你model.answers会这个样子，并将于[String : Answer]类型：

model.answers = ["id1" : Answer(text : "answer 1"), "id2" : Answer(text: "answer 2"), "id3":Answer(text: "answer 3")] 

的想法是，而不是有model.answers包含字符串，它们包含我们由被叫应答，可保持文本的轨道新的自定义类型对于答案（这是一个名为String类型的文本的属性）以及它是否是s当选（这是一个名为wasSelected的属性Bool）。您的for循环现在看起来像这样：

for (id, answer) in model.answers { 
    let answerLabel = UILabel() 
    answerLabel.text = answer.text //this comes from our new class definition 

    answersStack.addArrangedSubview(answerLabel) 
    //Change this to our new custom button subclass 
    let answerButton = ButtonWithAnswer() 
    //this line straight up won't work since you got rid of index 
    //answerButton.tag = index 

    //use this instead 
    answerButton.answer = answer 
    let imageNormal = UIImage(named: "circle_empty") 
    answerButton.setImage(imageNormal, for: .normal) 
    let imageSelected = UIImage(named: "circle_filled") 
    answerButton.setImage(imageSelected, for: .selected) 

    //make it so that any answers that were previously selected are now selected when the view reloads 
    answerButton.isSelected = answer.wasSelected 


    answerButton.setTitleColor(.black, for: .normal) 
    answerButton.addTarget(self, action: #selector(answerPressed(_:)), for: .touchUpInside) 
    answersStack.addArrangedSubview(answerButton) 


} 

这里有一个最后一部分。当我们点击与该答案相对应的按钮时，我们需要确保我们的答案被选中。所以在回答我们应该做这样的事情。

func answerPressed(_ sender : UIButton){ 
    let answerForButton = (sender as! ButtonWithAnswer).answer! 
    answerForButton.wasSelected = true 


} 

这应该关于掩盖它。如果这看起来像是一个全新的东西，那么在你潜入之前，你应该在Swift中查找关于Swift中的类，对象和init方法的教程，或者亲自向程序员请求帮助。但我尽可能地解释了这一点，而没有真正亲自到场给你一个完整的演练。