UIAlertController 自定义字体、大小、颜色 [英] UIAlertController custom font, size, color
问题描述
我正在使用新的 UIAlertController 来显示警报.我有这个代码:
I am using new UIAlertController for showing alerts. I have this code:
// nil titles break alert interface on iOS 8.0, so we'll be using empty strings
UIAlertController *alert = [UIAlertController alertControllerWithTitle: title == nil ? @"": title message: message preferredStyle: UIAlertControllerStyleAlert];
UIAlertAction *defaultAction = [UIAlertAction actionWithTitle: cancelButtonTitle style: UIAlertActionStyleCancel handler: nil];
[alert addAction: defaultAction];
UIViewController *rootViewController = [UIApplication sharedApplication].keyWindow.rootViewController;
[rootViewController presentViewController:alert animated:YES completion:nil];
现在我想更改标题和消息的字体、颜色、大小等.这样做的最佳方法是什么?
Now I want to change title and message font, color, size and so. What's best way to do this?
我应该插入整个代码.我为 UIView 创建了类别,我可以为 iOS 版本显示正确的警报.
I should insert whole code. I created category for UIView that I could show right alert for iOS version.
@implementation UIView (AlertCompatibility)
+( void )showSimpleAlertWithTitle:( NSString * )title
message:( NSString * )message
cancelButtonTitle:( NSString * )cancelButtonTitle
{
float iOSVersion = [[UIDevice currentDevice].systemVersion floatValue];
if (iOSVersion < 8.0f)
{
UIAlertView *alert = [[UIAlertView alloc] initWithTitle: title
message: message
delegate: nil
cancelButtonTitle: cancelButtonTitle
otherButtonTitles: nil];
[alert show];
}
else
{
// nil titles break alert interface on iOS 8.0, so we'll be using empty strings
UIAlertController *alert = [UIAlertController alertControllerWithTitle: title == nil ? @"": title
message: message
preferredStyle: UIAlertControllerStyleAlert];
UIAlertAction *defaultAction = [UIAlertAction actionWithTitle: cancelButtonTitle
style: UIAlertActionStyleCancel
handler: nil];
[alert addAction: defaultAction];
UIViewController *rootViewController = [UIApplication sharedApplication].keyWindow.rootViewController;
[rootViewController presentViewController:alert animated:YES completion:nil];
}
}
推荐答案
不确定这是否违反私有 API/属性,但在 ios8 上使用 KVC 对我有用
Not sure if this is against private APIs/properties but using KVC works for me on ios8
UIAlertController *alertVC = [UIAlertController alertControllerWithTitle:@"Dont care what goes here, since we're about to change below" message:@"" preferredStyle:UIAlertControllerStyleActionSheet];
NSMutableAttributedString *hogan = [[NSMutableAttributedString alloc] initWithString:@"Presenting the great... Hulk Hogan!"];
[hogan addAttribute:NSFontAttributeName
value:[UIFont systemFontOfSize:50.0]
range:NSMakeRange(24, 11)];
[alertVC setValue:hogan forKey:@"attributedTitle"];
UIAlertAction *button = [UIAlertAction actionWithTitle:@"Label text"
style:UIAlertActionStyleDefault
handler:^(UIAlertAction *action){
//add code to make something happen once tapped
}];
UIImage *accessoryImage = [UIImage imageNamed:@"someImage"];
[button setValue:accessoryImage forKey:@"image"];
作为记录,也可以使用这些私有 API 更改警报操作的字体.同样,它可能会让你的应用被拒绝,我还没有尝试提交这样的代码.
For the record, it is possible to change alert action's font as well, using those private APIs. Again, it may get you app rejected, I have not yet tried to submit such code.
let alert = UIAlertController(title: nil, message: nil, preferredStyle: .ActionSheet)
let action = UIAlertAction(title: "Some title", style: .Default, handler: nil)
let attributedText = NSMutableAttributedString(string: "Some title")
let range = NSRange(location: 0, length: attributedText.length)
attributedText.addAttribute(NSKernAttributeName, value: 1.5, range: range)
attributedText.addAttribute(NSFontAttributeName, value: UIFont(name: "ProximaNova-Semibold", size: 20.0)!, range: range)
alert.addAction(action)
presentViewController(alert, animated: true, completion: nil)
// this has to be set after presenting the alert, otherwise the internal property __representer is nil
guard let label = action.valueForKey("__representer")?.valueForKey("label") as? UILabel else { return }
label.attributedText = attributedText
对于 XCode 10 及更高版本中的 Swift 4.2,最后两行现在是:
For Swift 4.2 in XCode 10 and up the last 2 lines are now:
guard let label = (action!.value(forKey: "__representer")as? NSObject)?.value(forKey: "label") as? UILabel else { return }
label.attributedText = attributedText
这篇关于UIAlertController 自定义字体、大小、颜色的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!