在 xcode 中以编程方式设置焦点并显示键盘?
问题描述：
这是我的编码，即在单击 UIButton 时以编程方式创建 UITextField.但要增强的是，我想在创建 UITextField 时将焦点(并显示键盘)设置为新的 UITextField.
Here is my coding that UITextField is programmatically created when click on UIButton. But to enhancement is I want to set focus (and show keyboard) to new UITextField when UITextField is being created.
UITextField * txtComp=[[UITextField alloc]initWithFrame:CGRectMake(20,y, 450, 50)];
txtComp.borderStyle=UITextBorderStyleNone;
txtComp.delegate = self;
txtComp.tag=i+1;
txtComp.section=index;
txtComp.placeholder = @"New UITextField";
[txtComp becomeFirstResponder];
以上编码的工作是创建新的 UITextField，但即使设置了 becomeFirstResponder，也根本无法将焦点设置在新的 UITextField 上.
Above coding work as creating new UITextField but cannot be set focus on new UITextField at all even though becomeFirstResponder is set.
答
-(IBAction)buttonClicked:(id)sender
{
UITextField * txtComp=[[UITextField alloc]initWithFrame:CGRectMake(20,20, 450, 50)];
txtComp.borderStyle=UITextBorderStyleRoundedRect;
txtComp.delegate = self;
txtComp.placeholder = @"New UITextField";
[txtComp becomeFirstResponder];
[self.view addSubview:txtComp];
[self.view bringSubviewToFront:txtComp];
}