Question

我正在以编程方式创建按钮，然后我想添加功能，当按下/按下它们时，除非再次点击，否则它们会保持高亮显示。我现在正在做的是创建按钮，然后尝试添加IBAction。但是，问题是我在方法中创建了按钮，然后我不确定如何在IBAction中引用该按钮。这是我的代码：

UIButton* testButn = [UIButton buttonWithType:UIButtonTypeCustom];
  [testButn setFrame:CGRectMake(0, 135, 40, 38)];
  [testButn setImage:[UIImage imageNamed:@"test_butn_un.png"] forState:UIControlStateNormal];
  [testButn setImage:[UIImage imageNamed:@"test_butn_pressed.png"]   forState:UIControlStateHighlighted];
[testButn addTarget:self action:@selector(staypressed:) forControlEvents:UIControlEventTouchUpInside];
[self.contentview addSubview:testButn

-(IBAction)staypressed:(id)sender{

//Not sure what to do here, since this method doesn't recognize testButn, How do I reference testButn

Answer 1

发件人是testButn。您应该将stayPressed的参数类型从（id）更改为（UIButton *）

除非动作方法连接到几个不同类的对象，否则最好用您正在使用的任何对象类替换id。如果你在IB中挂钩，这可能很有用，因为它不会让你把它挂钩到错误的对象上。

它无效的事实不是因为它无法识别您的按钮。你的方法是错的。我认为您需要将一个动作连接到触地，并可能将所选状态设置为YES。在按钮定义中，您需要为所选状态设置imageForState :.你现在这样做的方式，直到修饰才会调用该方法。

这样的事情：

- (void)viewDidLoad
{
    [super viewDidLoad];
    UIButton* testButn = [UIButton buttonWithType:UIButtonTypeCustom];
    [testButn setFrame:CGRectMake(0, 135, 40, 38)];
    [testButn setImage:[UIImage imageNamed:@"New_PICT0019.jpg"] forState:UIControlStateNormal];
    [testButn setImage:[UIImage imageNamed:@"New_PICT0002.jpg"]   forState:UIControlStateSelected];
    [testButn addTarget:self action:@selector(stayPressed:) forControlEvents:UIControlEventTouchDown];
    [self.view addSubview:testButn];
}

-(void)stayPressed:(UIButton *) sender {
    if (sender.selected == YES) {
        sender.selected = NO;
    }else{
        sender.selected = YES;
    }
}

Answer 2

您需要将发件人转发给UIButton。

- (IBAction)staypressed:(id)sender
{
    UIButton *theButton = (UIButton*)sender;

    //do something to theButton
}

Answer 3

UIButton* testButn = [UIButton buttonWithType:UIButtonTypeCustom];
  [testButn setFrame:CGRectMake(0, 135, 40, 38)];
  [testButn setImage:[UIImage imageNamed:@"test_butn_un.png"] forState:UIControlStateNormal];
  [testButn setImage:[UIImage imageNamed:@"test_butn_pressed.png"]   forState:UIControlStateHighlighted];
  [testButn addTarget:self action:@selector(staypressed:) forControlEvents:UIControlEventTouchUpInside];
  testButn.tag = 1;
  [self.contentview addSubview:testButn

-(IBAction)staypressed:(id)sender
 {
     if ([sender tag]==1)
     {
         somecodes...
     }
 }

IBAction＆amp;按钮以编程方式

3 个答案: