使用iOS SDK:

我有一个带UITextFields的UIView,可以启动键盘。我需要它能够:

启动键盘后,允许滚动UIScrollView的内容以查看其他文本字段自动“跳转”(通过向上滚动)或缩短

我知道我需要一个UIScrollView。我已经尝试将UIView的类更改为UIScrollView,但仍然无法上下滚动文本框。

我需要UIView和UIScrollView吗?一个在另一个里面吗?

要自动滚动到活动文本字段,需要执行哪些操作?

理想情况下,尽可能多的组件设置将在Interface Builder中完成。我只想编写需要的代码。

注意:我使用的UIView(或UIScrollView)是由一个选项卡(UITabBar)启动的,它需要正常工作。


我正在添加滚动条,只为键盘出现时使用。尽管不需要它,但我觉得它提供了一个更好的界面,例如,用户可以滚动和更改文本框。

当键盘上下移动时,我可以改变UIScrollView的框架大小。我只是在使用:

-(void)textFieldDidBeginEditing:(UITextField *)textField {
    //Keyboard becomes visible
    scrollView.frame = CGRectMake(scrollView.frame.origin.x,
                                  scrollView.frame.origin.y,
    scrollView.frame.size.width,
    scrollView.frame.size.height - 215 + 50);   // Resize
}

-(void)textFieldDidEndEditing:(UITextField *)textField {
    // Keyboard will hide
    scrollView.frame = CGRectMake(scrollView.frame.origin.x,
                                  scrollView.frame.origin.y,
                                  scrollView.frame.size.width,
                                  scrollView.frame.size.height + 215 - 50); // Resize
}

然而,这不会自动“向上移动”或将可见区域中的下部文本字段居中,这是我真正想要的。


当前回答

@用户271753

要恢复原始视图,请添加:

-(BOOL)textFieldShouldReturn:(UITextField *)textField{
   [textField resignFirstResponder];
   [self setViewMovedUp:NO];
   return YES;
}

其他回答

有很多答案可以告诉我们这个方法。我采取了相同的方法,但实施效果不佳。

这是基本想法。我修改了keyboardWasShown方法。

{
// Obtain keyboard Info
NSDictionary* info = [notification userInfo];
CGRect keyboardRect = [[info objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue];
keyboardRect = [self.view convertRect:keyboardRect fromView:nil];

// Obtain ScrollView Info w.r.t. top View
CGRect scrollViewRect = [self.view convertRect:self.scrollView.frame fromView:nil];

// Depending upon your screen Ui, Scroll View's bottom edge might be at some offset from screen's bottom
// Calculate the exact offset
int scrollViewBottomOffset = self.view.frame.size.height - (scrollViewRect.origin.y + scrollViewRect.size.height);
int heightToBeAdjusted = keyboardRect.size.height - scrollViewBottomOffset;


// We may also need to consider the Insets if already present with ScrollView. Let's keep it simple for now
// But we should store these, so that we can restore the Insets when Keyboard is gone
// origInsets = self.scrollView.contentInset;

// Set the new Insets for ScrollView
UIEdgeInsets contentInsets = UIEdgeInsetsMake(0.0, 0.0, heightToBeAdjusted, 0.0);
self.scrollView.contentInset = contentInsets;
self.scrollView.scrollIndicatorInsets = contentInsets;

// Visible frame (not overlapped by Keyboard)
CGRect visibleFrame = self.view.frame;
visibleFrame.size.height -= keyboardRect.size.height;

// Get the Rect for Textfield w.r.t self.view
CGRect activeFieldFrame = self.activeField.frame;
activeFieldFrame = [self.view convertRect:activeFieldFrame fromView:self.scrollView];

// Check if the TextField is Visible or not
if (!CGRectContainsRect(visibleFrame, activeFieldFrame) ) {
    // Scroll to make it visible but for scrolling use the activeField frame w.r.t. to scroll View
    [self.scrollView scrollRectToVisible:self.activeField.frame animated:YES];
}

}

并添加此方法来初始化activeField

- (IBAction)textFieldDidBeginEditing:(UITextField *)sender
{
self.activeField = sender;
}

根据文档,从iOS 3.0开始,当有文本字段的在线编辑时,UITableViewController类会自动调整其表视图的大小并重新定位。我认为将文本字段放在UITableViewCell中是不够的,正如一些人所指出的那样。

从文档中:

表视图控制器支持表视图行的内联编辑;例如,如果行在编辑模式下嵌入了文本字段滚动虚拟键盘上方正在编辑的行显示。

这是使用Swift的解决方案。

import UIKit

class ExampleViewController: UIViewController, UITextFieldDelegate {

    @IBOutlet var scrollView: UIScrollView!

    @IBOutlet var textField1: UITextField!
    @IBOutlet var textField2: UITextField!
    @IBOutlet var textField3: UITextField!
    @IBOutlet var textField4: UITextField!
    @IBOutlet var textField5: UITextField!

    var activeTextField: UITextField!

    // MARK: - View
    override func viewDidLoad() {
        super.viewDidLoad()
        self.textField1.delegate = self
        self.textField2.delegate = self
        self.textField3.delegate = self
        self.textField4.delegate = self
        self.textField5.delegate = self
    }

    override func viewWillAppear(animated: Bool) {
        super.viewWillAppear(animated)
        self.registerForKeyboardNotifications()
    }

    override func viewWillDisappear(animated: Bool) {
        super.viewWillDisappear(animated)
        self.unregisterFromKeyboardNotifications()
    }

    // MARK: - Keyboard

    // Call this method somewhere in your view controller setup code.
    func registerForKeyboardNotifications() {
        let center:  NSNotificationCenter = NSNotificationCenter.defaultCenter()
        center.addObserver(self, selector: "keyboardWasShown:", name: UIKeyboardDidShowNotification, object: nil)
        center.addObserver(self, selector: "keyboardWillBeHidden:", name: UIKeyboardWillHideNotification, object: nil)
    }

    func unregisterFromKeyboardNotifications () {
        let center:  NSNotificationCenter = NSNotificationCenter.defaultCenter()
        center.removeObserver(self, name: UIKeyboardDidShowNotification, object: nil)
        center.removeObserver(self, name: UIKeyboardWillHideNotification, object: nil)
    }

    // Called when the UIKeyboardDidShowNotification is sent.
    func keyboardWasShown (notification: NSNotification) {
        let info : NSDictionary = notification.userInfo!
        let kbSize = (info.objectForKey(UIKeyboardFrameBeginUserInfoKey)?.CGRectValue() as CGRect!).size

        let contentInsets: UIEdgeInsets = UIEdgeInsetsMake(0.0, 0.0, kbSize.height, 0.0);
        scrollView.contentInset = contentInsets;
        scrollView.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, self.activeTextField.frame.origin) ) {
            self.scrollView.scrollRectToVisible(self.activeTextField.frame, animated: true)
        }
    }

    // Called when the UIKeyboardWillHideNotification is sent
    func keyboardWillBeHidden (notification: NSNotification) {
        let contentInsets = UIEdgeInsetsZero;
        scrollView.contentInset = contentInsets;
        scrollView.scrollIndicatorInsets = contentInsets;
    }

    // MARK: -  Text Field

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

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

}

在iOS中,向上移动键盘并收回应用程序中的文本字段有点令人困惑,需要实现一些相同的方法。此外,您还需要向textfield委派并处理它。它的代码将在存在文本字段的每个类中重复。

我更喜欢使用这个Github控件。

IQ键盘

在哪儿我们不需要做任何事情。——只需将拖放控件拖到项目中并构建。--它将为您的应用程序提供所有功能。

谢谢

也许这会有用。

在这里,我找到了处理键盘的最简单的解决方案。

您只需复制粘贴到示例代码下面,然后更改文本字段或任何要向上移动的视图。

步骤-1

只需在控制器中复制粘贴以下两种方法

- (void)registerForKeyboardNotifications
{
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWasShown:)
                                                 name:UIKeyboardDidShowNotification object:nil];
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillBeHidden:)
                                                 name:UIKeyboardWillHideNotification object:nil];
}

- (void)deregisterFromKeyboardNotifications
{
    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardDidHideNotification object:nil];
    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillHideNotification object:nil];
}

步骤-2

在视图中注册和注销键盘通知WillAppear和viewWillDisappear方法。

- (void)viewWillAppear:(BOOL)animated
{
    [super viewWillAppear:animated];
    [self registerForKeyboardNotifications];
}

- (void)viewWillDisappear:(BOOL)animated
{
    [self deregisterFromKeyboardNotifications];
    [super viewWillDisappear:animated];
}

步骤-3

灵魂部分来了,只要替换你的文本字段,然后改变高度你想向上移动多少。

- (void)keyboardWasShown:(NSNotification *)notification
{
    NSDictionary* info = [notification userInfo];
    CGSize currentKeyboardSize = [[info objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;

    //you need replace your textfield instance here
    CGPoint textFieldOrigin = self.tokenForPlaceField.frame.origin;
    CGFloat textFieldHeight = self.tokenForPlaceField.frame.size.height;

    CGRect visibleRect = self.view.frame;
    visibleRect.size.height -= currentKeyboardSize.height;

    if (!CGRectContainsPoint(visibleRect, textFieldOrigin))
    {
        //you can add yor desired height how much you want move keypad up, by replacing "textFieldHeight" below

        CGPoint scrollPoint = CGPointMake(0.0, textFieldOrigin.y - visibleRect.size.height  + textFieldHeight); //replace textFieldHeight to currentKeyboardSize.height, if you want to move up with more height
        [self.scrollView setContentOffset:scrollPoint animated:YES];
    }
}

- (void)keyboardWillBeHidden:(NSNotification *)notification
{
    [self.scrollView setContentOffset:CGPointZero animated:YES];
}

参考:好吧,请感谢这位分享了这个漂亮的代码片段、干净的解决方案的人。

希望这对外面的人会很有帮助。