视图向上移动时如何滚动文本字段？

Question

我在注册屏幕上有文本字段，所以当键盘出现时我向上移动视图。现在我想在视图向上移动时滚动文本字段。

向上移动视图的代码：

         CGRect rect = self.view.frame;
         rect.origin.y += 220;
         rect.size.height -= 220;
         self.view.frame = rect;

这是雇佣兵

我在顶部有UIScrollView，然后在UIScrollView 下我有UIView 我称之为contentView。在contentView 上我添加了一些文本字段。所以我的父视图向上移动了，但我当我查看时，我无法上下滚动文本字段。我为滚动设置了以下值。

    self.cvHeight.constant=500;
    self.scrollView.contentSize=CGSizeMake(500, 500);

这里cvHeight 是contentView 的高度约束出口，scrollView 是UIScrollView 的出口

编辑： 当我没有向上移动 self.view 的父视图时，我可以滚动浏览，但是如果我向上移动父视图，那么我的文本字段不会向下滚动，它们只是向上移动。

Answer 1

当您使用 UIScrollView 时，这将是最适合您的。使用TPKeyboardAvoidingScrollView

如何使用？ 很简单

要与 UITableViewController 类一起使用，请将 TPKeyboardAvoidingTableView.m 和 TPKeyboardAvoidingTableView.h 放入您的项目中，并将您的 UITableView 设置为 xib 中的 TPKeyboardAvoidingTableView。如果您没有在控制器中使用 xib，我知道没有简单的方法使其 UITableView 成为自定义类：阻力最小的路径是为其创建 xib。

对于非 UITableViewControllers，将 TPKeyboardAvoidingScrollView.m 和 TPKeyboardAvoidingScrollView.h 源文件拖放到项目中，将 UIScrollView 弹出到视图控制器的 xib 中，将滚动视图的类设置为 TPKeyboardAvoidingScrollView，然后将所有控件放在该滚动视图中。您也可以通过编程方式创建它，而无需使用 xib - 只需使用 TPKeyboardAvoidingScrollView 作为您的顶级视图。

Answer 2

- (void)keyboardWillShow:(NSNotification*)notification
{
    CGSize keyboardSize = [[[notification userInfo] objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;
    UIEdgeInsets contentInsets = UIEdgeInsetsMake(0.0,0.0,keyboardSize.height, 0.0);

    self.scrollViewPost.contentInset = contentInsets;
    self.scrollViewPost.scrollIndicatorInsets = contentInsets;

    CGRect rect = self.scrollViewPost.frame;
    rect.size.height = keyboardSize.height+_scrollViewPost.frame.size.height+84;


    if (!CGRectContainsPoint(rect, self.txtPost.frame.origin))
    {
        CGPoint scrollPoint = CGPointMake(0.0, 264+Table_Y);
        [self.scrollViewPost setContentOffset:scrollPoint animated:NO];
        self.viewPutPost.frame=CGRectMake(0, _viewPutPost.frame.origin.y-254, 320, 30);


    }
}

- (void)keyboardWillHide:(NSNotification *)notification
{
    UIEdgeInsets contentInsets = UIEdgeInsetsZero;
    self.scrollViewPost.contentInset = contentInsets;
    self.scrollViewPost.scrollIndicatorInsets = contentInsets;

    self.viewPutPost.frame=CGRectMake(0,537 , 320, 30);

}

Answer 3

ViewController.h

#import <UIKit/UIKit.h>
@interface SignUp : UIViewController <UIScrollViewDelegate>
{

}
@property (nonatomic, assign) UITextField *activeTextField;

ViewController.m

@implementation SignUp
@synthesize activeTextField;

- (void)viewDidLoad
{


    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWasShown:) name:UIKeyboardDidShowNotification object:nil];

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

    [super viewDidLoad];
    // Do any additional setup after loading the view from its nib.
}

#pragma mark - Textfield

- (void)keyboardWasShown:(NSNotification *)notification
{

    // Step 1: Get the size of the keyboard.
    CGSize keyboardSize = [[[notification userInfo] objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;


    // Step 2: Adjust the bottom content inset of your scroll view by the keyboard height.
    UIEdgeInsets contentInsets = UIEdgeInsetsMake(0.0, 0.0, keyboardSize.height, 0.0);

    _scrl.contentInset = contentInsets;
    _scrl.scrollIndicatorInsets = contentInsets;


    // Step 3: Scroll the target text field into view.
    CGRect aRect = self.view.frame;
    aRect.size.height -= keyboardSize.height;
    if (!CGRectContainsPoint(aRect, self.activeTextField.frame.origin) )
    {
        CGPoint scrollPoint = CGPointMake(0.0, self.activeTextField.frame.origin.y - (keyboardSize.height));
        [_scrl setContentOffset:scrollPoint animated:YES];
    }
}
- (void) keyboardWillHide:(NSNotification *)notification {

    UIEdgeInsets contentInsets = UIEdgeInsetsZero;
    _scrl.contentInset = contentInsets;
    _scrl.scrollIndicatorInsets = contentInsets;
}
- (void)textFieldDidEndEditing:(UITextField *)textField
{
    self.activeTextField = nil;
}

- (void)textFieldDidBeginEditing:(UITextField *)textField
{
    self.activeTextField = textField;


}

- (BOOL)textFieldShouldReturn:(UITextField *)textField;              // called when 'return' key pressed. return NO to ignore.
{
    if(textField == _txt_name)
    {
        [_txt_email becomeFirstResponder];
        return NO;
    }
    else if(textField == _txt_email)
    {
        [_txt_pwd becomeFirstResponder];
        return NO;
    }
    else if(textField == _txt_pwd)
    {
        [_txt_repwd becomeFirstResponder];
        return YES;
    }
    else if (textField == _txt_repwd)
    {
        [textField resignFirstResponder];
        return YES;
    }
    else
    {
        return YES;
    }
}

Answer 4

您不必向上移动整个视图。

相反，根据需要更改滚动视图的 contentOffset 属性，并在键盘启动时相应地增加 scrollView.contentSize。 当键盘向下时，将 scrollView.contentOffset 设置为 CGPointZero 和 scrollView.contentSize

键盘启动时：

CGFloat yOffset = ;             //Set According to the textField
self.scrollView.contentOffset = CGPointMake(0,-yOffset);

//Increase content size to enable scrolling till the end.
CGFloat contentHeight =  self.crollView.contentSize.height + keyboardHeight;

self.scrollView.contentSize = CGSizeMake(kScreenWidth, contentHeight);     

当键盘关闭时：

self.scrollView.contentOffset = CGPointMake(0,0);

//Increase content size to enable scrolling till the end.
CGFloat contentHeight =  self.crollView.contentSize.height - keyboardHeight;

self.crollView.contentSize = CGSizeMake(kScreenWidth, contentHeight);     

增加内容大小将使您能够在键盘向上时滚动滚动视图直到底部。