Question

如果这是一件简单的事情我很抱歉，我仍然是客观C的新手。我有一个按钮，我试图改变每次按下它的图像和文本，但我的问题是，它一直在经历每一次，直到IBAction结束。我需要做什么，每次点击按钮只做1“if”？谢谢

-(IBAction)Button1:(UIButton *)sender {
if (button1TapCount == 0) {
    button1TapCount = 1;
    textString = (@"Button 1 Pressed");
    button1ImageName  = (@"test.png");
    [self buttonschange];
}
if (button1TapCount == 1) {
    button1TapCount = 2;
    textString = (@"Button 1 Pressed twice");
    button1ImageName  = (@"test1.png");
    [self buttonschange];
}
if (button1TapCount == 2) {
    button1TapCount = 3;
    textString = (@"Button 1 Pressed third time");
    button1ImageName  = (@"test2.png");
    [self buttonschange];
}
}

Answer 1

这是因为您没有使用else并且您正在更改每个button1TapCount语句中的if，以便 next { {1}}将其解析为真。

使用：

if

Answer 2

在第一个如果您将button1TapCount设置为1，那么第二个if也是如此。我认为你需要的是其他如果：

-(IBAction)Button1:(UIButton *)sender {
    if (button1TapCount == 0) {
        button1TapCount = 1;
        textString = (@"Button 1 Pressed");
        button1ImageName  = (@"test.png");
        [self buttonschange];
    }
    else if (button1TapCount == 1) {
        button1TapCount = 2;
        textString = (@"Button 1 Pressed twice");
        button1ImageName  = (@"test1.png");
        [self buttonschange];
    }
    else if (button1TapCount == 2) {
        button1TapCount = 3;
        textString = (@"Button 1 Pressed third time");
        button1ImageName  = (@"test2.png");
        [self buttonschange];
    }
}

Answer 3

使用 if-else 或返回或切换

-(IBAction)Button1:(UIButton *)sender {
if (button1TapCount == 0) {
    button1TapCount = 1;
    textString = (@"Button 1 Pressed");
    button1ImageName  = (@"test.png");
    [self buttonschange];
return;
}
if (button1TapCount == 1) {
    button1TapCount = 2;
    textString = (@"Button 1 Pressed twice");
    button1ImageName  = (@"test1.png");
    [self buttonschange];
return;
}
if (button1TapCount == 2) {
    button1TapCount = 3;
    textString = (@"Button 1 Pressed third time");
    button1ImageName  = (@"test2.png");
    [self buttonschange];
return;

}
}

按钮按1按钮按下所有if语句 - 目标C

3 个答案: