iOS 键盘上方添加自定义按钮

UIToolbarkeyboardDoneButtonView = [[UIToolbar alloc]init];
// keyboardDoneButtonView.frame=CGRectMake(0, 0, , <#CGFloat height#>)
[keyboardDoneButtonView sizeToFit];
UIBarButtonItemdoneButton1 = [[UIBarButtonItem alloc] initWithTitle:@""

                                                                                             style:UIBarButtonItemStyleBordered target:self
                              
                                                                                            action:@selector(doneClicked:)];
[doneButton1 setWidth:[UIScreen mainScreen].bounds.size.width-50];
UIBarButtonItem*doneButton2 = [[UIBarButtonItem alloc] initWithTitle:@"Done"
                              
                                                                                             style:UIBarButtonItemStyleBordered target:self
                              
                                                                                            action:@selector(doneClicked:)];
[doneButton2 setWidth:50];
[keyboardDoneButtonView setItems:[NSArray arrayWithObjects:doneButton1,doneButton2,nil]];

self.textField.inputAccessoryView = keyboardDoneButtonView;