在常规UIViewController上的UITableViewCell中将UITextField滚动到键盘上方

Question

我在StackOverflow上尝试了大部分示例.我也用过Apple.我似乎与他们有的问题是他们没有考虑UITextField在UITableView中.我已经做了很多次,但不是这样.我有一个带有UITextField的自定义UITableViewCell.

在我的UITableView(不是UITableViewController)上,我需要能够避免在UITableView下隐藏UITextField.

我现在有这个:

-(void)viewDidLoad
{
....
    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(keyboardWillShow:)
                                                 name:UIKeyboardWillShowNotification
                                               object:nil];

    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(keyboardWillHide:)
                                                 name:UIKeyboardWillHideNotification
                                               object:nil];

....
}

- (void)scrollToRectOfTextField {
    UITableViewCell *cell = (UITableViewCell*)[self.activeTextField superview];
    CGRect r = CGRectMake(self.activeTextField.frame.origin.x,
                          cell.frame.origin.y+self.activeTextField.frame.origin.y,
                          self.activeTextField.frame.size.width,
                          self.activeTextField.frame.size.height);
    [self.tableView scrollRectToVisible:r animated:YES];
}

- (void)keyboardDidShow:(NSNotification *)notification
{
    if (UI_USER_INTERFACE_IDIOM()== UIUserInterfaceIdiomPhone) {
        NSDictionary *userInfo = [notification userInfo];
        CGSize size = [[userInfo objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue].size;
        NSLog(@"TableView: %@", NSStringFromCGRect(self.tableView.frame));
        CGRect newTableViewFrame = CGRectMake(self.tableView.frame.origin.x,
                                              self.tableView.frame.origin.y,
                                              self.tableView.frame.size.width, self.tableView.frame.size.height - size.height);
        self.tableView.frame = newTableViewFrame;
        NSLog(@"New TableView: %@", NSStringFromCGRect(self.tableView.frame));


        self.tableView.contentSize = CGSizeMake(self.tableView.contentSize.width, self.tableView.contentSize.height-size.height);
    }
}


- (void)keyboardWillHide:(NSNotification *)notification
{
    NSDictionary *userInfo = [notification userInfo];
    CGSize size = [[userInfo objectForKey: UIKeyboardFrameEndUserInfoKey] CGRectValue].size;
    self.tableView.frame = CGRectMake(self.tableView.frame.origin.x,
                                      self.tableView.frame.origin.y,
                                      self.tableView.frame.size.width,
                                      self.tableView.frame.size.height + size.height);

    NSLog(@"%@", NSStringFromCGRect(self.tableView.frame));
}


-(void)textFieldDidBeginEditing
{
     [self scrollToRectOfTextField];
}

这似乎把一堆空白区域推到我的键盘上方.另请注意,我的UITextField上也有一个inputAccessoryView.

哦,我不能使用任何第三方课程.我喜欢TPKeyboardAvoidingScrollView,但我不能使用任何第三方.

Answer 1

我花了一整天的时间试图解决这个问题.我在这里发布了它,然后找到了一个博客链接和一个非常简单的解决方案.它看起来像这样:

-(BOOL)textFieldShouldBeginEditing:(UITextField *)textField {
    CGPoint pointInTable = [textField.superview convertPoint:textField.frame.origin toView:self.tableView];
    CGPoint contentOffset = self.tableView.contentOffset;

    contentOffset.y = (pointInTable.y - textField.inputAccessoryView.frame.size.height);

    NSLog(@"contentOffset is: %@", NSStringFromCGPoint(contentOffset));

    [self.tableView setContentOffset:contentOffset animated:YES];

    return YES;
}


-(BOOL)textFieldShouldEndEditing:(UITextField *)textField
{
    [textField resignFirstResponder];

    if ([textField.superview.superview isKindOfClass:[UITableViewCell class]])
    {
        UITableViewCell *cell = (UITableViewCell*)textField.superview.superview;
        NSIndexPath *indexPath = [self.tableView indexPathForCell:cell];

        [self.tableView scrollToRowAtIndexPath:indexPath atScrollPosition:UITableViewScrollPositionMiddle animated:TRUE];
    }

    return YES;
}

检查iOS 8

Answer 2

我尝试了@inturbidus为iOS8发布的链接,但不幸的是它对我不起作用.经过一番挖掘后,事实证明Apple确实在他们的网站上有示例代码,以便像在UITableViewController中那样自然地完成这项工作.这是Objective-C版本的Apple链接,我也在这里添加了swift版本.

来自Apple的Objective-C链接(滚动到清单5-1): https ://developer.apple.com/library/ios/documentation/StringsTextFonts/Conceptual/TextAndWebiPhoneOS/KeyboardManagement/KeyboardManagement.html

快速调整Objective-C版本

var activeField: UITextField?

func textFieldDidBeginEditing(textField: UITextField) {
    self.activeField = textField
}

func textFieldDidEndEditing(textField: UITextField) {
    self.activeField = nil
}

func registerForKeyboardNotifications() {
    NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyboardWasShown:", name: UIKeyboardDidShowNotification, object: nil)
    NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyboardWillBeHidden:", name: UIKeyboardWillHideNotification, object: nil)
}    

func keyboardWasShown(aNotification: NSNotification) {
    let info = aNotification.userInfo as! [String: AnyObject],
    kbSize = (info[UIKeyboardFrameBeginUserInfoKey] as! NSValue).CGRectValue().size,
    contentInsets = UIEdgeInsets(top: 0, left: 0, bottom: kbSize.height, right: 0)

    self.tableView.contentInset = contentInsets
    self.tableView.scrollIndicatorInsets = contentInsets

    // If active text field is hidden by keyboard, scroll it so it's visible
    // Your app might not need or want this behavior.
    var aRect = self.view.frame
    aRect.size.height -= kbSize.height

    if !CGRectContainsPoint(aRect, activeField!.frame.origin) {
        self.tableView.scrollRectToVisible(activeField!.frame, animated: true)
    }
}

func keyboardWillBeHidden(aNotification: NSNotification) {
    let contentInsets = UIEdgeInsetsZero
    self.tableView.contentInset = contentInsets
    self.tableView.scrollIndicatorInsets = contentInsets
}

Answer 3

我把马特和萨尔曼的答案混在了一起.这适用于tableView中的许多文本字段.斯威夫特3

基本上是得到了textInput触及的BOTTOM Y点.一旦我们有了,我检查键盘是否覆盖textInput,如果这样做,我会改变tableView的contentOffset

首先注册通知.在init中,如果是UIView,或者在viewDidLoad中,如果是UIViewController:

    NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow), name: NSNotification.Name.UIKeyboardWillShow, object: nil)
    NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillHide), name: NSNotification.Name.UIKeyboardWillHide, object: nil)

然后将触摸的文本字段设置为当前输入

var inputActive: UITextField!

func textViewShouldBeginEditing(_ textView: UITextView) -> Bool {
    inputActive = textInput
    return true
}

最后实现通知方法:

func keyboardWillShow(notification: NSNotification) {
    var userInfo = notification.userInfo!
    if let keyboardFrame = (userInfo[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue {
        // Get my height size
        let myheight = tableView.frame.height
        // Get the top Y point where the keyboard will finish on the view
        let keyboardEndPoint = myheight - keyboardFrame.height
        // Get the the bottom Y point of the textInput and transform it to the currentView coordinates.
        if let pointInTable = inputActive.superview?.convert(inputActive.frame.origin, to: tableView) {
            let textFieldBottomPoint = pointInTable.y + inputActive.frame.size.height + 20
            // Finally check if the keyboard will cover the textInput
            if keyboardEndPoint <= textFieldBottomPoint {
                tableView.contentOffset.y = textFieldBottomPoint - keyboardEndPoint
            } else {
                tableView.contentOffset.y = 0
            }
        }
    }
}

func keyboardWillHide(notification: NSNotification) {
    tableView.contentOffset.y = 0
}

很少有东西要补充.该填充是一些额外的距离,我在我的情况下加了20分.同样在我的情况下,UITableView被添加到UIViewController,但这也应该在UITableViewController中工作

希望这可以帮助!

Answer 4

感谢@Salman的链接.
请注意,Apple示例在普通视图中用于scrollview.
在表视图中,您必须将activeField的Point和Rect转换为表的坐标,因此我更改了函数keyboardWasShown中的一些行:

func keyboardWasShown(aNotification: NSNotification) {
        let info = aNotification.userInfo as! [String: AnyObject],
        kbSize = (info[UIKeyboardFrameBeginUserInfoKey] as! NSValue).CGRectValue().size,
        contentInsets = UIEdgeInsets(top: 0, left: 0, bottom: kbSize.height, right: 0)

        self.tableBasket.contentInset = contentInsets
        self.tableBasket.scrollIndicatorInsets = contentInsets

        var aRect = self.view.frame
        aRect.size.height -= kbSize.height

        let pointInTable = activeField!.superview!.convertPoint(activeField!.frame.origin, toView: tableView)
        let rectInTable = activeField!.superview!.convertRect(activeField!.frame, toView: tableView)

        if !CGRectContainsPoint(aRect, pointInTable) {
            self.tableView.scrollRectToVisible(rectInTable, animated: true)
        }
}

如果您的视图有tabBarController,请记住重置具有tabBar高度而不是UIEdgeInsetsZero的contentInsets(如果没有,您的最后一行可能隐藏在tabBar下):

func keyboardWillBeHidden(aNotification: NSNotification) {
        //UIEdgeInsetsZero is used in view without tabBar
        //let contentInsets = UIEdgeInsetsZero
        let tabBarHeight = self.tabBarController!.tabBar.frame.height
        let contentInsets = UIEdgeInsets(top: 0, left: 0, bottom: tabBarHeight, right: 0)
        self.tableView.contentInset = contentInsets
        self.tableView.scrollIndicatorInsets = contentInsets
    }
}

Answer 5

我的解决方案（适用于 Xcode 8.3.3、Swift 3、iOS 10.3.1）：

class MyTableViewController: UITableViewController {

    override func viewWillAppear(_ animated: Bool) {
        NotificationCenter.default.addObserver(self, selector: #selector(actionKeyboardDidShow(with:)), name: .UIKeyboardDidShow, object: nil)
        NotificationCenter.default.addObserver(self, selector: #selector(actionKeyboardWillHide(with:)), name: .UIKeyboardWillHide, object: nil)
    }

    override func viewDidDisappear(_ animated: Bool) {
        NotificationCenter.default.removeObserver(self, name: .UIKeyboardDidShow, object: nil)
        NotificationCenter.default.removeObserver(self, name: .UIKeyboardWillHide, object: nil)
    }

    @objc private func actionKeyboardDidShow(with notification: Notification) {
        guard let userInfo = notification.userInfo as? [String: AnyObject],
            let keyboardFrame = (userInfo[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue
            else { return }

        var contentInset = self.tableView.contentInset
        contentInset.bottom += keyboardFrame.height

        self.tableView.contentInset = contentInset
        self.tableView.scrollIndicatorInsets = contentInset
    }

    @objc private func actionKeyboardWillHide(with notification: Notification) {
        guard let userInfo = notification.userInfo as? [String: AnyObject],
            let keyboardFrame = (userInfo[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue
            else { return }

        var contentInset = self.tableView.contentInset
        contentInset.bottom -= keyboardFrame.height

        self.tableView.contentInset = contentInset
        self.tableView.scrollIndicatorInsets = contentInset
    }

}