Question

我想在按下指定方法时传递一个uibutton的标记，但是当我尝试这个时，我会收到一条错误消息。请帮忙。代码：

   UIButton *deleteButton  = [[UIButton alloc]initWithFrame:CGRectMake(230, dateLabel.frame.origin.y, 70, 27)];
    [deleteButton addTarget:self action:@selector(deleteButtonPressed:i) forControlEvents:UIControlEventTouchDown];
    [deleteButton setBackgroundImage:[UIImage imageNamed:@"delete.jpg"] forState:UIControlStateNormal];
    [deleteButton setTag:i];

然后

    -(void)deleteButtonPressed:(int)tag
{
    NSLog(@"Button Pressed");
    NSLog(@"%i", tag);


}

Answer 1

事件处理程序不会自行传递标记，它们会传递整个按钮：

UIButton *deleteButton  = [[UIButton alloc]initWithFrame:CGRectMake(230, dateLabel.frame.origin.y, 70, 27)];
[deleteButton addTarget:self action:@selector(deleteButtonPressed:) forControlEvents:UIControlEventTouchDown];
[deleteButton setBackgroundImage:[UIImage imageNamed:@"delete.jpg"] forState:UIControlStateNormal];
[deleteButton setTag:i];

现在你可以从传入的按钮中获取标签，如下所示：

-(void)deleteButtonPressed:(UIButton*)button {
    NSLog(@"Button Pressed, tag=%i", button.tag);
}

Answer 2

您无法在@selector中传递参数。那应该是@selector（deleteButtonPressed :)。

然后在动作方法中：

    -(void)deleteButtonPressed:(UIButton *) sender
{
    NSLog(@"Button Pressed");
    NSLog(@"%d", sender.tag);


}

如何在印刷机上传递uibutton的标签

2 个答案: