- (void)viewDidLoad

{

    [super viewDidLoad];

    UITextField *input=[[UITextField alloc] initWithFrame:CGRectMake(0, 100, 200, 100)];

    self.textfield=input;

    [input setText:@"hahah"];

    input.textAlignment=NSTextAlignmentCenter;

    input.contentVerticalAlignment=UIControlContentVerticalAlignmentCenter;

    input.contentHorizontalAlignment=UIControlContentHorizontalAlignmentCenter;

    input.backgroundColor = [[UIColor blackColor] colorWithAlphaComponent:0.5];

    input.textColor=[UIColor blueColor];

    input.keyboardAppearance=UIKeyboardAppearanceLight;

//    input.alpha=0;

    input.tintColor=[[UIColor redColor] colorWithAlphaComponent:0.5];

    [self.view addSubview:input];

}

UITextField 属性