iPad - 以编程方式将文本设置为按钮

Question

我是这个iPad业务的新手，我正在基于XML文件的内容以编程方式在scrollview中创建一些按钮。我有这个代码：

float x = (SLIDER_ELEMENT_HEIGHT * i) + 20;
CGRect frame = CGRectMake(x, 0, SLIDER_ELEMENT_WIDTH, SLIDER_ELEMENT_HEIGHT);
UIButton *button = [[UIButton alloc] initWithFrame:frame];

UIColor *bgColor = [[UIColor alloc] initWithRed:1.0 green:1.0 blue:1.0 alpha:1.0];
button.backgroundColor = bgColor;

NSString *titleForButton = [NSString stringWithFormat: @"This is my title"];
[button setTitle:titleForButton forState:(UIControlStateNormal | UIControlStateApplication | UIControlStateHighlighted)];

UIColor *fgColor = [[UIColor alloc] initWithRed:0.5 green:0.5 blue:0.5 alpha:1.0];
[button setTitleColor:fgColor forState:(UIControlStateNormal | UIControlStateApplication | UIControlStateHighlighted)];

[button addTarget:self action:@selector(buttonMethod:) forControlEvents:(UIControlEvents)UIControlEventTouchDown];
[scrl_lastIssues addSubview:button];

现在，我追加的方法监听器工作正常，但按钮的文本从未出现......我做错了什么？

Answer 1

尝试更改行：

  [button setTitle:titleForButton forState:(UIControlStateNormal | UIControlStateApplication | UIControlStateHighlighted)];

至：

  [button setTitle:titleForButton forState:UIControlStateNormal];

forState参数不能按照您当前的预期工作，它的工作方式如下：

  [button setTitle:@"Normal" forState:UIControlStateNormal];
  [button setTitle:@"Highlighted" forState:UIControlStateHighlighted];

Answer 2

此外，如果您只设置UIControlStateNormal文本..它将是您通过按位OR分隔的所有控件状态的文本，我相信，这是您要搜索的功能。

Answer 3

[button setTitle:@"Return" forState:UIControlStateNormal];
    [button setTitleColor:[UIColor greenColor] forState:UIControlStateNormal];
    [button setBackgroundColor:[UIColor orangeColor]];

Answer 4

如果你想为所有州设置相同的标题，那么这样做：

[button setTitle:titleForButton forState:UIControlStateNormal];
[button setTitle:titleForButton forState:UIControlStateHighlighted];