objective-c - 如何删除或隐藏子图层？

Question

-(IBAction)displayinfo:(id)sender
{
    sublayer = [CALayer layer];

    if (appear == NO)
    {
        appear = YES;
        sublayer.contents=(id)[UIImage imageNamed:@"infoPalette.png"].CGImage;
        sublayer.frame= CGRectMake(300,200,350,250);
        [self.view.layer addSublayer:sublayer];
    }
    else
    {
        [sublayer removeFromSuperlayer];
    }
}

这允许图层出现，但我无法在单击同一按钮时将其删除或隐藏。

Answer 1

用这个替换你现有的代码

-(IBAction)displayinfo:(id)sender
{

    if ( appear == NO)
    {
         sublayer = [CALayer layer];
         appear = YES;
         sublayer.contents=(id)[UIImage imageNamed:@"infoPalette.png"].CGImage;
         sublayer.frame= CGRectMake(300,200,350,250);
         [self.view.layer addSublayer:sublayer];
    }
    else
    {
        [sublayer removeFromSuperlayer];
    }
}