Xcode 测验也有同样的问题

我有一个类似测验的应用程序。它经常显示所有的问题。我怎样才能让他们只出现一次，这样在最后一个问题之后，就会弹出一条消息

func nextText(){
        let randomNumber = Int(arc4random_uniform(4))
        var textLabel = "" as NSString
        switch (randomNumber){
        case 1:
            textLabel = "Question1."
            break
        case 2:
            textLabel = "Question2."
            break
        case 3:
            textLabel = "Question3."
            break
        case 4:
            textLabel = "Question4."
            break
        default:
            textLabel = "Question 5"
        }
        self.textLabel.text = textLabel as? String
    }
}

---

只需在箱子里换一种方式：

func nextText(){
        let randomNumber = Int(arc4random_uniform(4))
        var textLabel = "" as NSString
        switch (randomNumber){
        case 1:
            textLabel = "Question1."
            self.textLabel.text = textLabel as? String
            break
        case 2:
            textLabel = "Question2."
            self.textLabel.text = textLabel as? String
            break
        case 3:
            textLabel = "Question3."
            self.textLabel.text = textLabel as? String
            break
        case 4:
            textLabel = "Question4."
            self.textLabel.text = textLabel as? String
            break
        default:
            textLabel = "Question 5"
            self.textLabel.text = textLabel as? String
        }
    }

---

也许您可以将问题存储为一个数组。然后创建了一系列新的混合问题。然后运行数组，将问题呈现给用户。在数组中找到最后一个问题后，可以显示弹出消息。下面是一个例子：

1。从

3.列举你的问题：

let questions = ["Question1", "Question2", "Question3", "Question4"]
let shuffledQuestions = questions.shuffled()

var questionIndex = 0

for question in shuffledQuestions {
    //  Present the question to the user
    self.textLabel.text = question
    questionIndex++
}

---

4.用户完成最后一个问题后，弹出窗口。例如，当

questionIndex==shuffledQuestions.count

定义一个可变数组时。将随机数添加到数组中。检查数组中是否存在随机数。如果其存在，则复制一个随机数

这是你在目标c中的问题：

//Defining an array
@property NSMutableArray *asked;


-(void) nextText{
//This will generate a random number between 1 and 5.
int randomNumber = arc4random() % 5+1;

NSString * textLabel =nil;

//This will check all questions are asked
if ([asked count] ==5) {
    self.myLabel.text = @"All questions completed";
    return;
}

//This will check is random number asked
if ([asked containsObject:[NSString stringWithFormat:@"%i",randomNumber]]) {
    return;
}

//This will add random number to asked questions and will ask the question of random number
else{
    [asked addObject:[NSString stringWithFormat:@"%i",randomNumber]];
    switch (randomNumber){
        case 1:
            textLabel = @"Question1.";
            break;
        case 2:
            textLabel = @"Question2.";
            break;
        case 3:
            textLabel = @"Question3.";
            break;
        case 4:
            textLabel = @"Question4.";
            break;
        case 5:
            textLabel = @"Question5.";
            break;
    }
    self.myLabel.text = textLabel;
  }
}

//If you want more than limited question, create and fill question array 
//After you can ask like this. Change else part with this
else{
    [asked addObject:[NSString stringWithFormat:@"%i",randomNumber]];
    self.myLabel.text = [questions objectAtIndex:randomNumber];
    }

---

你为什么不把问题放在一个数组中，每次你展示一个问题时就从中弹出？所以你可以这样做：

var questions = ["Question1", "Question2", "Question3", "Question4", "Question5"]

for var i = questions.count; i > 0; {
    let randomNumber = Int(arc4random_uniform(UInt32(--i)))
    let textLabel = questions[randomNumber] as String
    println(textLabel)
    questions.removeAtIndex(randomNumber)
}

if questions.count == 0 {
    println("should show the popup")
}

---

您所做的只是更改设置

textlab.text

，此代码的结果与问题中的代码完全相同。@ABakerSmith我收到了所有不同的结果。但我认为问题要求不要重复这些问题。除非我误解了。这种方法的问题是，当你向数组中添加更多的数字时，选择一个尚未选择的数字的概率会降低。当只有五个问题时，这不是什么大问题。但是如果有更多的问题，这可能会花费相当长的时间来创建问题的顺序。如果您不想只问5个问题，您可以为问题创建更多的数组。并将开关部分置于回路中。例如：//这将向询问的问题添加随机数，并询问随机数的问题{[asked addObject:[NSString stringWithFormat:@“%i”，randomNumber]]；self.myLabel.text=[questions objectAtIndex:randomNumber]；}

var questions = ["Question1", "Question2", "Question3", "Question4", "Question5"]

for var i = questions.count; i > 0; {
    let randomNumber = Int(arc4random_uniform(UInt32(--i)))
    let textLabel = questions[randomNumber] as String
    println(textLabel)
    questions.removeAtIndex(randomNumber)
}

if questions.count == 0 {
    println("should show the popup")
}