Question

我有一个按钮，按下后会打开一个新视图。

override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
let secondViewController:ContasView = segue.
destinationViewController as! ContasView

我不希望在标签值不为零之前启用它。我通常将这种按钮看作灰色文本按钮。那么，有两个问题： 1.如何禁用这种情况？ 2.一旦禁用，如何变成灰色文本按钮？

Answer 1

开始聆听：

textField1.addTarget(self, action: "textFieldDidChange:", forControlEvents: UIControlEvents.EditingChanged)
textField2.addTarget(self, action: "textFieldDidChange:", forControlEvents: UIControlEvents.EditingChanged)
textField3.addTarget(self, action: "textFieldDidChange:", forControlEvents: UIControlEvents.EditingChanged)

检查值：

func textFieldDidChange(textField: UITextField) {
    button.enabled = !textField1.text.isEmpty && !textField2.text.isEmpty && !textField3.text.isEmpty

Answer 2

var button = UIButton(frame: CGRect(x: 0, y: 0, width: 100, height: 100))
    button.userInteractionEnabled = false
    button.setTitle("ButtonTextHere", forState: .Normal)
    button.setTitleColor(UIColor.grayColor(), forState: .Normal)
    view.addSubview(button)

代码中的某处，只要标签发生变化，您就可以

button.userInteractionEnabled = true
button.setTitleColor(UIColor.blueColor(), forState: .Normal)

禁用按钮并将其变为灰色

2 个答案: