UIButton *share = [UIButton buttonWithType:UIButtonTypeCustom];
// 普通状态显示的图片(selected=NO)
UIImage *shareNormal = [UIImage imageNamed:@"XXX.png"];
[share setBackgroundImage:shareNormal forState:UIControlStateNormal];
// 选中状态显示的图片(selected=YES)
[share setBackgroundImage:[UIImage imageNamed:@"XXX.png"] forState:UIControlStateSelected];
share.center = CGPointMake(start.center.x, start.center.y - 50);
share.bounds = (CGRect){CGPointZero, shareNormal.size};
[share addTarget:self action:@selector(share:) forControlEvents:UIControlEventTouchUpInside];
// 代表按钮变为UIControlStateDisabled状态
// share.enabled = NO;
// 设置选中
share.selected = YES;
// 按钮在高亮的时候不需要变灰色
share.adjustsImageWhenHighlighted = NO;
[imageView addSubview:share];
#pragma mark 点击事件
- (void)share:(UIButton *)btn
{
btn.selected = !btn.selected;
}