当键盘出现在 iOS 中时启用滚动内容
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【中文标题】当键盘出现在 iOS 中时启用滚动内容【英文标题】:Enable scrolling content when keyboard appears in iOS 【发布时间】:2015-09-25 06:11:33 【问题描述】:我在 iPhone 上有一个应用程序,它在 viewcontroller 中有很多内容。一般主要内容是形式。我的问题是我放了键盘,想输入一些值来形成字段,大部分内容是不可见的。我想在键盘出现时滚动这个内容。我怎样才能做到这一点? 我的视图没有滚动视图,但我尝试这样做但它不起作用。
到目前为止,我发现的所有提示都涉及如何放置使用过的文本框,但这不是我的假设。
【问题讨论】:
***.com/questions/1126726/… 的可能重复项 在主视图上添加滚动视图? 【参考方案1】:这就是我所做的,当键盘像这样上下升降时,我改变了顶部约束-
在viewDidLoad
调用这个方法-
[self observeKeyboard];
#pragma mark- Keyboard Listen Methods
- (void)observeKeyboard
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillShow:) name:UIKeyboardWillChangeFrameNotification object:nil];
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillHide:) name:UIKeyboardWillHideNotification object:nil];
- (void)keyboardWillShow:(NSNotification *)notification
NSDictionary *info = [notification userInfo];
NSValue *kbFrame = [info objectForKey:UIKeyboardFrameEndUserInfoKey];
NSTimeInterval animationDuration = [[info objectForKey:UIKeyboardAnimationDurationUserInfoKey] doubleValue];
CGRect keyboardFrame = [kbFrame CGRectValue];
CGFloat height = keyboardFrame.size.height;
self.COnstraintTopViewVertical.constant=(value of constant)-height;
[UIView animateWithDuration:animationDuration animations:^
[self.view layoutIfNeeded];
];
- (void)keyboardWillHide:(NSNotification *)notification
NSDictionary *info = [notification userInfo];
NSTimeInterval animationDuration = [[info objectForKey:UIKeyboardAnimationDurationUserInfoKey] doubleValue];
self.ConstraintTopViewVertical.constant=reset value;
[UIView animateWithDuration:animationDuration animations:^
[self.view layoutIfNeeded];
];
【讨论】:
【参考方案2】:您可以使用以下代码在键盘出现时以编程方式更改视图中的位置:
func keyboardWasShown(notification: NSNotification)
UIView.animateWithDuration(0.3, animations: () -> Void in
self.setContentOffset(CGPoint(x: setXOffsetHere, y: setYOffsetHere), animated: true)
)
此代码将在键盘出现后将视图转换到您在 .setContentOffset 调用中指定的坐标。您仍然需要获取坐标,但通常从情节提要中获取坐标非常简单。
【讨论】:
【参考方案3】:-
将所有视图放在滚动视图中
设置从滚动视图底部到超级视图底部的自动布局约束
在viewWillAppear
[[NSNotificationCenter defaultCenter] addObserver:self
selector:@selector(keyboardWillChangeFrame:)
name:UIKeyboardWillChangeFrameNotification object:nil];
处理知识库通知
- (void)keyboardWillChangeFrame:(NSNotification*)aNotification
CGRect kbFrame = [aNotification.userInfo[UIKeyboardFrameEndUserInfoKey] CGRectValue];
CGRect kbWindowIntersectionFrame = CGRectIntersection(self.view.window.bounds, kbFrame);
[UIView animateWithDuration:[aNotification.userInfo[UIKeyboardAnimationDurationUserInfoKey] doubleValue] animations:^
self.scrollVBottomConstraint.constant = kbWindowIntersectionFrame.size.height;
[self.view layoutIfNeeded];
];
【讨论】:
【参考方案4】:what i got from your question is: you are using textfield on UIView which is not on the scrollview, now you have to scroll the UIView when keyboard appears. just do following stuff.
-Give the tag to your textfield.
-suppose tag you have given is 4545646
-do not forgot to assign delegate to your textfield (it will execute below delegate method when you start to edit)
- (void)textFieldDidBeginEditing:(UITextField *)textField
if (textField.tag == 4545646)
UIView *contanerView = [self.view viewWithTag:5556466];
[UIView animateWithDuration:0.5 animations:^
contanerView.frame = CGRectMake(self.view.frame.origin.x+1, -85, self.view.frame.size.width, self.view.frame.size.height-9);
];
Change the frame as per your requirement.
and
- (void)textFieldDidEndEditing:(UITextField *)textField
if (textField.tag == 4545646)
[textField resignFirstResponder];
UIView *contanerView = [self.view viewWithTag:5556466];
[UIView animateWithDuration:0.5 animations:^
contanerView.frame = CGRectMake(self.view.frame.origin.x+1, self.view.frame.origin.y, self.view.frame.size.width, self.view.frame.size.height);
];
【讨论】:
contanerView 是设置文本字段的视图【参考方案5】:在 viewDidAppear 添加以下通知
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyBoardShown:) name:UIKeyboardWillShowNotification object:nil];
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyBoardDismiss:) name:UIKeyboardWillHideNotification object:nil];
在keyBoardShown方法中获取键盘高度
- (void)keyBoardShown:(NSNotification*)notification
if(self.view.frame.origin.y>=0)
NSDictionary* keyboardInfo = [notification userInfo];
NSValue* keyboardFrameBegin = [keyboardInfo valueForKey:UIKeyboardFrameBeginUserInfoKey];
CGRect keyboardFrameBeginRect = [keyboardFrameBegin CGRectValue];
// NSLog(@"hihi : %f",keyboardFrameBeginRect.size.height);
keyBoardHeight = keyboardFrameBeginRect.size.height-yDeault+50;
if (keyBoardHeight>0)
[UIView beginAnimations:nil context:nil];
[UIView setAnimationDuration:0.5];
[UIView setAnimationCurve:UIViewAnimationCurveEaseOut];
self.view.frame = CGRectMake(self.view.frame.origin.x, (self.view.frame.origin.y-keyBoardHeight), self.view.frame.size.width, self.view.frame.size.height);
[UIView commitAnimations];
在 keyBoardDismiss 中将主视图 y 坐标回退到之前的值
-(void)keyBoardDismiss:(NSNotification*)notification
if(self.view.frame.origin.y<0)
[UIView beginAnimations:nil context:nil];
[UIView setAnimationDuration:0.5];
[UIView setAnimationCurve:UIViewAnimationCurveEaseOut];
self.view.frame = CGRectMake(self.view.frame.origin.x, (self.view.frame.origin.y+keyBoardHeight), self.view.frame.size.width, self.view.frame.size.height);
[UIView commitAnimations];
这里 yDeault 是文本域的 y 坐标值
yDeault= screenHeight-textField.frame.origin.y+textField.frame.size.height;
一旦显示键盘,主视图将向上移动,一旦键盘关闭,主视图将移回原始位置
【讨论】:
【参考方案6】:好的。我做了这个。我只需要添加滚动视图,但在我的应用程序中可能我必须重建我的所有视图。
【讨论】:
【参考方案7】:无需添加滚动视图。您可以直接执行此操作。您可以更改self.view.frame
而无需滚动视图。
【讨论】:
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