Question

这是我的按钮创建功能。

  -(void)buttonCreate {
  //oneBtn5 Button
  oneBtn5 = [UIButton buttonWithType:UIButtonTypeCustom];
  oneBtn5.frame = CGRectMake(316, 389, 51, 21);
  oneBtn5.tag = 5;
  [oneBtn5 setTitle:@"" forState:UIControlStateNormal];
  [oneBtn5 addTarget:self action:@selector(oneButton:) forControlEvents:UIControlEventTouchDown];
  [oneBtn5 setImage:[UIImage imageNamed:@"1c.png"] forState:UIControlStateNormal];
  [self.view addSubview:oneBtn5];
}

我将使用viewonload（），

显示按钮

- (void)viewDidLoad {
   [super viewDidLoad];
   [self buttonCreate];
 }

这是我的重启功能，如果我点击重启，新按钮就会创建。

- (void)RestartAction {
    [self buttonCreate];
  }

我的问题是当我点击重启时如何删除重复按钮。它有办法解决这个问题。

Answer 1

只需从其超级视图中删除按钮：

-(void)buttonCreate {
    if (oneBtn5.superView) {
        [oneBtn5 removeFromSuperview];
    }
   ....
}

Answer 2

-(void)buttonCreate {
  //oneBtn5 Button
  if (oneBtn5 != null)
      [oneBtn5 removeFromSuperview];

  oneBtn5 = [UIButton buttonWithType:UIButtonTypeCustom];
  oneBtn5.frame = CGRectMake(316, 389, 51, 21);
  oneBtn5.tag = 5;
  [oneBtn5 setTitle:@"" forState:UIControlStateNormal];
  [oneBtn5 addTarget:self action:@selector(oneButton:) forControlEvents:UIControlEventTouchDown];
  [oneBtn5 setImage:[UIImage imageNamed:@"1c.png"] forState:UIControlStateNormal];
  [self.view addSubview:oneBtn5];
}

Answer 3

你可以在buttonCreate中执行此操作

if(oneBtn5==nil)
{
     oneBtn5 = [UIButton buttonWith....];
     [self.view addsubview: oneBtn5;
}

按钮仅插入并添加一次

Answer 4

将此用作：

-(void)buttonCreate {
    if ([self.view.subviews containsObject:oneBtn5]) {
            [oneBtn5 removeFromSuperview];
        }
   // YOUR CODE HERE
}

Answer 5

如果是属性，就像人们告诉你的那样，检查它是否存在。

if(!self.oneBtn5){
     //instance of button
     self.oneBtn5 = [UIButton buttonWith....];
     [self.view addsubview: self.oneBtn5];

}else{
     //change stuff you need like text or frame

}

问题是您正在创建按钮的新实例，而不是重复使用前一个按钮。

Answer 6

-(void)buttonCreate {
  //oneBtn5 Button
  if (oneBtn5 ){
      [oneBtn5 removeFromSuperview];
       oneBtn5=nil;   // release the memory
      }

  oneBtn5 = [UIButton buttonWithType:UIButtonTypeCustom];
  oneBtn5.frame = CGRectMake(316, 389, 51, 21);
  oneBtn5.tag = 5;
  [oneBtn5 setTitle:@"" forState:UIControlStateNormal];
  [oneBtn5 addTarget:self action:@selector(oneButton:) forControlEvents:UIControlEventTouchDown];
  [oneBtn5 setImage:[UIImage imageNamed:@"1c.png"] forState:UIControlStateNormal];
  [self.view addSubview:oneBtn5];
}

您必须在oneBtn = nil之后写[oneBtn5 removeFromSuperview]以释放先前创建的按钮的内存。当[oneBtn5 removeFromSuperview];从超级视图中删除按钮但不释放内存。您必须通过将其设置为nil来释放内存。

如何删除重复按钮

6 个答案: