输入附件视图（工具栏）

在键盘上方添加附件视图。这通常用于添加下一个/上一个按钮，或其他按钮，如完成/提交（特别是对于没有内置返回键的数字/电话/小数点键盘类型）。

迅速

let textField = UITextField() // initialized however

let toolbar = UIToolbar(frame: CGRect(x: 0, y: 0, width: view.frame.size.width, height: 0)

let flexibleSpace = UIBarButtonItem(barButtonSystemItem: .FlexibleSpace, target: nil, action: nil)

let doneButton = UIBarButtonItem(barButtonSystemItem: .Done, target: self, action: Selector("done"))

let items = [flexibleSpace, doneButton]  // pushes done button to right side

toolbar.setItems(items, animated: false) // or toolbar.items = ...
toolbar.sizeToFit()

textField.inputAccessoryView = toolbar

Objective-C

UITextField *textField = [[UITextField alloc] init];

UIToolbar *toolbar = [[UIToolbar alloc] initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, 0)];

UIBarButtonItem *flexibleSpace = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:nil action:nil];
UIBarButtonItem *doneButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemDone target:self action:@selector(done)];
NSArray *items = @[
                   flexibleSpace,
                   doneButton
                   ];

[toolbar setItems:items];
[toolbar sizeToFit];

textField.inputAccessoryView = toolbar;