我有一个包含十几个不同视图控制器的项目。全部使用相同的代码来设置导航栏的背景,如下所示:
CGRect frame = CGRectMake(0, 0, [self.title sizeWithFont:[UIFont fontWithName:@"HelveticaNeue" size:28]].width, 44);
UILabel *titleLabel = [[UILabel alloc] initWithFrame:frame];
titleLabel.text = @"Categories";
titleLabel.font = [UIFont fontWithName:@"HelveticaNeue" size:22];
titleLabel.backgroundColor = UIColorFromRGBWithAlpha(0x84A537, 0.5);
titleLabel.textAlignment = NSTextAlignmentCenter;
self.navigationItem.titleView = titleLabel;
self.navigationController.navigationBar.tintColor = UIColorFromRGBWithAlpha(0x84A537, 0.5);
self.navigationItem.titleView.backgroundColor = [UIColor clearColor];
self.navigationController.view.backgroundColor = UIColorFromRGBWithAlpha(0x84A537, 0.1);
除了标题文本为灰色背景的 CollectionView 之外,它们都可以正常工作。我复制并粘贴了其他 VC 的代码。我不知道我在做什么来造成这种情况。我像这样设置颜色十六进制值:
//RGB color macro
#define UIColorFromRGB(rgbValue) [UIColor \
colorWithRed:((float)((rgbValue & 0xFF0000) >> 16))/255.0 \
green:((float)((rgbValue & 0xFF00) >> 8))/255.0 \
blue:((float)(rgbValue & 0xFF))/255.0 alpha:1.0]
//RGB color macro with alpha
#define UIColorFromRGBWithAlpha(rgbValue,a) [UIColor \
colorWithRed:((float)((rgbValue & 0xFF0000) >> 16))/255.0 \
green:((float)((rgbValue & 0xFF00) >> 8))/255.0 \
blue:((float)(rgbValue & 0xFF))/255.0 alpha:a]