iOS 15 的新 ConfigurationUpdateHandler 用于 Objective-C 中的 UIButton 的示例

Question

我想试用 iOS15 中提供的新 UIButtonConfigurationUpdateHandler 来创建切换按钮。有很多非常好的示例使用 Swift（like this one by Sarunw，但我的大部分代码库是 Objective-C。有人可以提供有关如何为我动态配置按钮的示例代码吗？谢谢！

Answer 1

也许这会让你上路...

#import <UIKit/UIKit.h>

@interface BtnCfgViewController : UIViewController
{
    BOOL bIsOn;
}
@end

@implementation BtnCfgViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    
    bIsOn = NO;
    
    if (@available(iOS 15.0, *)) {
        
        UIAction *tapAction = [UIAction actionWithHandler:^(UIAction* action){
            self->bIsOn = !self->bIsOn;
        }];
        
        UIButtonConfiguration *cfg = [UIButtonConfiguration plainButtonConfiguration];
        
        UIButton *myButton = [UIButton buttonWithConfiguration:cfg
                                                 primaryAction:tapAction];
        
        myButton.configurationUpdateHandler = ^(UIButton *btn) {
            UIButtonConfiguration *cfg = btn.configuration;
            NSString *s = [NSString stringWithFormat:@"Toggle: %@", self->bIsOn ? @"☑︎" : @"☐"];
            cfg.title = s;
            btn.configuration = cfg;
        };
        
        myButton.translatesAutoresizingMaskIntoConstraints = NO;
        [self.view addSubview:myButton];
        
        UILayoutGuide *g = [self.view safeAreaLayoutGuide];
        
        [NSLayoutConstraint activateConstraints:@[
            
            [myButton.topAnchor constraintEqualToAnchor:g.topAnchor constant:20.0],
            [myButton.widthAnchor constraintEqualToConstant:200.0],
            [myButton.heightAnchor constraintEqualToConstant:60.0],
            [myButton.centerXAnchor constraintEqualToAnchor:g.centerXAnchor],
            
        ]];
        
    }
    
}

iOS 15 的新 ConfigurationUpdateHandler 用于 Objective-C 中的 UIButton 的示例

Example for using iOS 15's new ConfigurationUpdateHandler for a UIButton in Objective-C

objective-c

uibutton

ios