将叠加视图添加到Swift中的文本字段

Question

我正在尝试向Swift中的UITextField添加叠加视图（添加发送按钮等）。 UITextField的Apple API参考（以及Google上的其他任何地方）仅显示如何在Objective-C中执行此操作（如下所示）。任何人都可以告诉我如何在Swift中执行此操作，或指向我更新的API参考？提前谢谢！

UIButton* overlayButton = [UIButton buttonWithType:UIButtonTypeCustom];
[overlayButton setImage:[UIImage imageNamed:@"bookmark"] forState:UIControlStateNormal];
[overlayButton addTarget:self action:@selector(displayBookmarks:)
forControlEvents:UIControlEventTouchUpInside];
overlayButton = CGRectMake(0, 0, 28, 28);

// Assign the overlay button to a stored text field
self.textField.leftView = overlayButton;
self.textField.leftViewMode = UITextFieldViewModeAlways;

Answer 1

Swift翻译的代码将是

let overlayButton = UIButton(type: .custom)
overlayButton.setImage(UIImage(named: ""), for: .normal)
overlayButton.addTarget(self, action: #selector(displayBookmarks(_:)), for: .touchUpInside)
overlayButton = CGRectMake(0, 0, 28, 28);


// Assign the overlay button to a stored text field
self.textField.leftView = overlayButton;
self.textField.leftViewMode = UITextFieldViewModeAlways;

Answer 2

试试这个：

self.textField.addSubview（overlayButton）