iOS开发之一些实用小知识点总结
时间：2021-04-06 10:01:24|栏目：iOS代码|点击： 次
话不多说，直接进主题
一、防止UIButton，cell等重复点击
主要是快速点击button或者cell，所对应的action或者逻辑会走多次，例如：点击button或者cell调用拨打电话的方法，会弹出拨打电话框好多次；这个对用户不太友好；问了下哥们儿，他给了个宏，目前算是解决这个问题；代码如下：
// 防止多次调用
#define kPreventRepeatClickTime(_seconds_) \
static BOOL shouldPrevent; \
if (shouldPrevent) return; \
shouldPrevent = YES; \
dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)((_seconds_) * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{ \
shouldPrevent = NO; \
}); \
总的思路是设置一个bool变量，记录一下，延时更改下变量的值；使用：在所需要的button或者cell的action前调用即可：
kPreventRepeatClickTime(0.5);
二、获取当前视图最顶层的ViewController
获取当前视图最顶层的ViewController
+ (UIViewController *)currentViewController {
UIWindow * window = [[UIApplication sharedApplication] keyWindow];
if (window.windowLevel != UIWindowLevelNormal){
NSArray *windows = [[UIApplication sharedApplication] windows];
for(UIWindow * tmpWin in windows){
if (tmpWin.windowLevel == UIWindowLevelNormal){
window = tmpWin;
break;
}
}
}
UIViewController *currentVC = window.rootViewController;
while (currentVC.presentedViewController) {
currentVC = currentVC.presentedViewController;
}
if ([currentVC isKindOfClass:[UITabBarController class]]) {
currentVC = [(UITabBarController *)currentVC selectedViewController];
}
if ([currentVC isKindOfClass:[UINavigationController class]]) {
currentVC = [(UINavigationController *)currentVC topViewController];
}
return currentVC;
}
三、代码截图相关
截取指定的View：
/// 截屏
- (void)actionForScreenShotWith:(UIView *)aimView savePhoto:(BOOL)savePhoto {
if (!aimView) return;
UIGraphicsBeginImageContextWithOptions(aimView.bounds.size, NO, 0.0f);
[aimView.layer renderInContext: UIGraphicsGetCurrentContext()];
UIImage* viewImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
if (savePhoto) {
/// 保存到本地相册
UIImageWriteToSavedPhotosAlbum(viewImage, self, @selector(image:didFinishSavingWithError:contextInfo:), NULL);
}
}
保存图片的回调处理
- (void)image:(UIImage*)image didFinishSavingWithError:(NSError*)error contextInfo:(void*)contextInfo{
if (error) {
NSLog(@"保存失败，请重试");
} else {
NSLog(@"保存成功");
}
}
总结
