[英]iOS UITextField resignFirstResponder on viewWillDisappear
我有两个简单屏幕的应用程序。 第一个屏幕始终打开第二个屏幕的相同实例。 第二个屏幕有一个text field
和一个手动隐藏keyboard
的button
。
viewWillDisappear
上的resignFirstResponder
无法正常工作。
情况1:
案例2:
码:
@implementation MainViewController
-(void) viewDidLoad {
[super viewDidLoad];
UIStoryboard *sb = [UIStoryboardWithName:@"Main" bundle:nil];
self.searchView = (SearchViewController*) [sb instantiateViewControllerWithIdentifier:@"searchView"];
}
- (IBAction)openSearchButtonClicked:(id)sender{
[self.navigationController pushViewController:self.searchView animated:YES];
}
@end
@implementation SearchViewController
- (void)viewWillDisappear:(BOOL)animated{
assert(self.searchTextField != nil);
[self.searchTextField resignFirstResponder];
[super viewWillDisappear:animated];
}
- (IBAction)hideKeyboardButtonClicked:(id)sender{
[self.searchTextField resignFirstResponder];
}
@end
我通过解决方法解决了这个问题。 重新打开searchView后,我检查了textFieldDidBeginEditing的堆栈跟踪。 不知怎的,UIKit决定在文本字段上调用becomeFirstResponder。
我的解决方案是:在视图控制器出现之前,不允许文本字段成为第一响应者。 但是,iOS 10.2上仍会出现闪烁的白屏。
- (void)viewDidAppear:(BOOL)animated{
[super viewDidAppear:animated];
self.allowToBecomeFirstResponser = YES;
}
- (BOOL)textFieldShouldBeginEditing:(UITextField *)textField{
return self.allowToBecomeFirstResponser ;
}
- (void)viewWillDisappear:(BOOL)animated{
self.allowToBecomeFirstResponser = NO;
[super viewWillDisappear:animated];
}
0 ??? 0x000000011d54d91c 0x0 + 4787067164,
1 DEMO 0x000000010c24d880 main + 0,
2 UIKit 0x000000010d60a227 -[UITextField _becomeFirstResponder] + 481,
3 UIKit 0x000000010d04d28d -[UIResponder becomeFirstResponder] + 324,
4 UIKit 0x000000010cf42e03 -[UIView(Hierarchy) becomeFirstResponder] + 99,
5 UIKit 0x000000010d609ad7 -[UITextField becomeFirstResponder] + 51,
6 UIKit 0x000000010cf42e3b -[UIView(Hierarchy) deferredBecomeFirstResponder] + 49,
7 UIKit 0x000000010cf43144 __45-[UIView(Hierarchy) _postMovedFromSuperview:]_block_invoke + 175,
8 UIKit 0x000000010cf43086 -[UIView(Hierarchy) _postMovedFromSuperview:] + 437,
9 UIKit 0x000000010cf4cf4b -[UIView(Internal) _addSubview:positioned:relativeTo:] + 1604,
10 UIKit 0x000000010cecf392 -[_UIParallaxDimmingView didMoveToWindow] + 123,
11 UIKit 0x000000010cf4a9a0 -[UIView(Internal) _didMoveFromWindow:toWindow:] + 1482,
12 UIKit 0x000000010cf4a68e -[UIView(Internal) _didMoveFromWindow:toWindow:] + 696,
13 UIKit 0x000000010cf43112 __45-[UIView(Hierarchy) _postMovedFromSuperview:]_block_invoke + 125,
14 UIKit 0x000000010cf43086 -[UIView(Hierarchy) _postMovedFromSuperview:] + 437,
15 UIKit 0x000000010cf4cf4b -[UIView(Internal) _addSubview:positioned:relativeTo:] + 1604,
16 UIKit 0x000000010cecbc38 __53-[_UINavigationParallaxTransition animateTransition:]_block_invoke + 2101,
17 UIKit 0x000000010cf475ce +[UIView(Animation) performWithoutAnimation:] + 65,
18 UIKit 0x000000010cecb072 -[_UINavigationParallaxTransition animateTransition:] + 1225,
19 UIKit 0x000000010d01fe6c -[UINavigationController _startCustomTransition:] + 3038,
20 UIKit 0x000000010d02b3fe -[UINavigationController _startDeferredTransitionIfNeeded:] + 386,
21 UIKit 0x000000010d02bf47 -[UINavigationController __viewWillLayoutSubviews] + 43,
22 UIKit 0x000000010d171509 -[UILayoutContainerView layoutSubviews] + 202,
-(BOOL) textFieldShouldReturn: (UITextField *) textField
{
[textField resignFirstResponder];
return YES;
}
但是你需要将UITextFieldDelegate
添加到你的SearchViewController中-(BOOL) textFieldShouldReturn:
在那里工作。
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.