iOS 13 适配

1、UIViewController切换方式modalPresentationStyle

iOS13默认UIModalPresentationAutomatic模式，不符合我们的需求。改回之前的模式要用UIModalPresentationFullScreen。

vc.modalPresentationStyle = UIModalPresentationFullScreen;

但是，问题来了，项目里vc太多，而且因为接入了多家SDK，viewController并没有一个相同父VC，全局改太费劲了。

解决方案：

在appDelegate中实现了ViewController的分类，改变了modalPresentationStyle的值完美解决。

@implementation UIViewController(modalPresentationStyle)
 
- (UIModalPresentationStyle)modalPresentationStyle{
 
    return UIModalPresentationFullScreen;
 
}
@end

 

 2、"NSGenericException" - reason: "Access to UITextField's _placeholderLabel ivar is prohibited. This is an application bug"

设置TextFiled的默认文字颜色在iOS13 Crash。

[textfield setValue:[UIColor whiteColor] forKeyPath:@"_placeholderLabel.textColor"];
 查了一下，帖子挺多的，解决方案：

Ivar ivar =  class_getInstanceVariable([UITextField class], "_placeholderLabel");
UILabel *placeholderLabel = object_getIvar(textField, ivar);
placeholderLabel.textColor = [UIColor whiteColor];
记得加头文件

#import  

 

3、去除TabBar黑线

iOS13 新增api  UITabBarAppearance

if (@available(iOS 13.0, *)) {//去除iOS13的TabBarg黑线

        UITabBarAppearance* tabbarAppearance =self.tabBar.standardAppearance;

        tabbarAppearance.backgroundImage = [self imageWithColor:[UIColor clearColor] size:self.tabBar.size];

        tabbarAppearance.shadowImage = [self imageWithColor:[UIColor clearColor] size:self.tabBar.size];

        self.tabBar.standardAppearance = tabbarAppearance;

    } else {

        self.tabBar.backgroundImage = [self imageWithColor:[UIColor clearColor] size:self.tabBar.size];

        self.tabBar.shadowImage = [self imageWithColor:[UIColor clearColor] size:self.tabBar.size];

    }

注： [self imageWithColor:[UIColor clearColor] size:self.tabBar.size]; 为根据控件size生成的纯色图片，代码如下

#pragma mark - 给出颜色值，制作纯色图片

- (UIImage *)imageWithColor:(UIColor *)color size:(CGSize)size {

    if (!color || size.width <=0 || size.height <=0) return nil;

    CGRect rect = CGRectMake(0.0f, 0.0f, size.width, size.height);

    UIGraphicsBeginImageContextWithOptions(rect.size,NO, 0);

    CGContextRef context =UIGraphicsGetCurrentContext();

    CGContextSetFillColorWithColor(context, color.CGColor);

    CGContextFillRect(context, rect);

    UIImage *image =UIGraphicsGetImageFromCurrentImageContext();

    UIGraphicsEndImageContext();

    return image;

}