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Get UITableView to scroll to the selected UITextField and Avoid Being Hidden by Keyboard

开发者 https://www.devze.com 2023-02-16 06:32 出处:网络
I have a UITextField in a table view on a UIViewController (not a UITableViewController). If the table view is on a UITableViewController, the table will automatically scroll to the textField being ed

I have a UITextField in a table view on a UIViewController (not a UITableViewController). If the table view is on a UITableViewController, the table will automatically scroll to the textField being edited to prevent it from being hidden by the keyboard. But on a UIViewController it does not.

I have tried for a couple of days reading through multiple ways to try to accomplish this and I cannot get it to work. The closest thing that actually scrolls is:

-(void) textFieldDidBeginEditing:(UITextField *)textField {

// SUPPOSEDLY Scroll to the current text field

CGRect textFieldRect = [textField frame];
[self.wordsTableView scrollRectToVisible:textFieldRect animated:YES];

}

However this only scrolls the table to the topmost row. What seems like an easy task has been a couple of days of frustration.

I am using the following to construct the tableView cells:

- (UITableViewCell *)tableView:(UITableView *)aTableView
    cellForRowAtIndexPath:(NSIndexPath *)indexPath {

NSString *identifier = [NSString stringWithFormat: @"%d:%d", [indexPath indexAtPosition: 0], [indexPath indexAtPosition:1]];

UITableViewCell *cell = [aTableView dequeueReusableCellWithIdentifier:identifier];

    if (cell == nil) {

        cell = [[[UITableViewCell alloc] 
        initWithStyle:UITableViewCellStyleDefault 
        reuseIdentifier:identifier] autorelease];

        cell.accessoryType = UITableViewCellAccessoryNone;

        UITextField *theTextField = [[UITextField alloc] initWithFrame:CGRectMake(180, 10, 130, 25)];

        theTextField.adjustsFontSizeToFitWidth = YES;
        theTextField.textColor = [UIColor redColor];
        theTextField.text = [textFieldArray objectAtIndex:indexPath.row];
        theTextField.keyboardType = UIKeyboardTypeDefault;
        theTextField.returnKeyType = UIReturnKeyDone;
        theTextField.font = [UIFont boldSystemFontOfSize:14];
        theTextField.backgroundColor = [UIColor whiteColor];
        theTextField.autocorrectionType = UITextAutocorrectionTypeNo;
        theTextField.autocapitalizationType开发者_StackOverflow = UITextAutocapitalizationTypeNone;
        theTextField.clearsOnBeginEditing = NO;
        theTextField.textAlignment = UITextAlignmentLeft;

        //theTextField.tag = 0;
        theTextField.tag=indexPath.row;

        theTextField.delegate = self;

        theTextField.clearButtonMode = UITextFieldViewModeWhileEditing;
        [theTextField setEnabled: YES];

        [cell addSubview:theTextField];

        [theTextField release];


}

return cell;
}

I suspect I can get the tableView to scroll properly if I can somehow pass the indexPath.row in the textFieldDidBeginEditing method?

Any help is appreciated.


In my app, I have successfully used a combination of contentInset and scrollToRowAtIndexPath like this:

When you want to display the keyboard, just add a contentInset at the bottom with your table with desired height:

tableView.contentInset =  UIEdgeInsetsMake(0, 0, height, 0);

Then, you can safely use

[tableView scrollToRowAtIndexPath:[NSIndexPath indexPathForRow:cell_index inSection:cell_section] animated:YES];

By adding the contentInset, even if you are focusing on the last cell the tableView will still be able to scroll. Just make sure that when you are dismissing the keyboard, you reset the contentInset.

EDIT:
If you have only one section (you can replace cell_section with 0) and the use the textView tag to inform the cell row.


Swift

@objc private func keyboardWillShow(_ notification: Notification) {
    guard let userinfo = notification.userInfo else {
        return
    }

    guard
        let duration = (userinfo[UIResponder.keyboardAnimationDurationUserInfoKey] as? NSNumber)?.doubleValue,
        let endFrame = (userinfo[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue,
        let curveOption = userinfo[UIResponder.keyboardAnimationCurveUserInfoKey] as? UInt else {
            return
    }
    
    UIView.animate(withDuration: duration, delay: 0, options: [.beginFromCurrentState, .init(rawValue: curveOption)], animations: {
        let edgeInsets = UIEdgeInsets(top: 0, left: 0, bottom: endFrame.height, right: 0)
        self.scrollView.contentInset = edgeInsets
        self.scrollView.scrollIndicatorInsets = edgeInsets
    })
}

@objc private func keyboardWillHide(_ notification: Notification) {
    guard let userinfo = notification.userInfo else {
        return
    }

    guard
        let duration = (userinfo[UIResponder.keyboardAnimationDurationUserInfoKey] as? NSNumber)?.doubleValue,
        let curveOption = userinfo[UIResponder.keyboardAnimationCurveUserInfoKey] as? UInt else {
            return
    }
    
    UIView.animate(withDuration: duration, delay: 0, options: [.beginFromCurrentState, .init(rawValue: curveOption)], animations: {
        let edgeInsets = UIEdgeInsets.zero
        self.scrollView.contentInset = edgeInsets
        self.scrollView.scrollIndicatorInsets = edgeInsets
    })
}


override func viewDidLoad() {
    super.viewDidLoad()
    
    // ...

    subscribeToKeyboardNotifications()
}

deinit {
    unsubscribeFromKeyboardNotifications()
}

private func subscribeToKeyboardNotifications() {
    NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow), name: UIWindow.keyboardWillShowNotification, object: nil)
    NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillHide), name: UIWindow.keyboardWillHideNotification, object: nil)
}

private func unsubscribeFromKeyboardNotifications() {
    NotificationCenter.default.removeObserver(self, name: UIWindow.keyboardWillShowNotification, object: nil)
    NotificationCenter.default.removeObserver(self, name: UIWindow.keyboardWillHideNotification, object: nil)
}

Objective C

- (void)keyboardWillShow:(NSNotification *)sender
{
    CGFloat height = [[sender.userInfo objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue].size.height;
    NSTimeInterval duration = [[sender.userInfo objectForKey:UIKeyboardAnimationDurationUserInfoKey] doubleValue];
    UIViewAnimationOptions curveOption = [[sender.userInfo objectForKey:UIKeyboardAnimationCurveUserInfoKey] unsignedIntegerValue] << 16;
    
    [UIView animateWithDuration:duration delay:0 options:UIViewAnimationOptionBeginFromCurrentState|curveOption animations:^{
        UIEdgeInsets edgeInsets = UIEdgeInsetsMake(0, 0, height, 0);
        tableView.contentInset = edgeInsets;
        tableView.scrollIndicatorInsets = edgeInsets;
    } completion:nil];
}

- (void)keyboardWillHide:(NSNotification *)sender
{
    NSTimeInterval duration = [[sender.userInfo objectForKey:UIKeyboardAnimationDurationUserInfoKey] doubleValue];
    UIViewAnimationOptions curveOption = [[sender.userInfo objectForKey:UIKeyboardAnimationCurveUserInfoKey] unsignedIntegerValue] << 16;

    [UIView animateWithDuration:duration delay:0 options:UIViewAnimationOptionBeginFromCurrentState|curveOption animations:^{
        UIEdgeInsets edgeInsets = UIEdgeInsetsZero;
        tableView.contentInset = edgeInsets;
        tableView.scrollIndicatorInsets = edgeInsets;
    } completion:nil];
}

And in - (void)viewDidLoad

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

Then

- (void)dealloc
{
    [[NSNotificationCenter defaultCenter] removeObserver:self];
}


This is a tweak to FunkyKat's answer (big thank you FunkyKat!). It would probably be beneficial to not hardcode UIEdgeInsetsZero for future iOS compatibility.

Instead, I ask for the current inset value and tweak the bottom value as needed.

- (void)keyboardWillShow:(NSNotification *)sender {
    CGSize kbSize = [[[sender userInfo] objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue].size;
    NSTimeInterval duration = [[[sender userInfo] objectForKey:UIKeyboardAnimationDurationUserInfoKey] doubleValue];

    CGFloat height = UIDeviceOrientationIsPortrait([[UIDevice currentDevice] orientation]) ? kbSize.height : kbSize.width;
    if (isIOS8()) height = kbSize.height;

    [UIView animateWithDuration:duration animations:^{
        UIEdgeInsets edgeInsets = [[self tableView] contentInset];
        edgeInsets.bottom = height;
        [[self tableView] setContentInset:edgeInsets];
        edgeInsets = [[self tableView] scrollIndicatorInsets];
        edgeInsets.bottom = height;
        [[self tableView] setScrollIndicatorInsets:edgeInsets];
    }];
}

- (void)keyboardWillHide:(NSNotification *)sender {
    NSTimeInterval duration = [[[sender userInfo] objectForKey:UIKeyboardAnimationDurationUserInfoKey] doubleValue];

    [UIView animateWithDuration:duration animations:^{
        UIEdgeInsets edgeInsets = [[self tableView] contentInset];
        edgeInsets.bottom = 0;
        [[self tableView] setContentInset:edgeInsets];
        edgeInsets = [[self tableView] scrollIndicatorInsets];
        edgeInsets.bottom = 0;
        [[self tableView] setScrollIndicatorInsets:edgeInsets];
    }];
}


For the sake of anyone else running into this issue, I'm posting the necessary methods here:

- (UITableViewCell *)tableView:(UITableView *)aTableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {

    NSString *identifier = [NSString stringWithFormat: @"%d:%d", [indexPath indexAtPosition: 0], [indexPath indexAtPosition:1]];

    UITableViewCell *cell = [aTableView dequeueReusableCellWithIdentifier:identifier];

    if (cell == nil) {

        cell = [[[UITableViewCell alloc]  initWithStyle:UITableViewCellStyleDefault reuseIdentifier:identifier] autorelease];

        UITextField *theTextField = [[UITextField alloc] initWithFrame:CGRectMake(180, 10, 130, 25)];

        theTextField.keyboardType = UIKeyboardTypeDefault;
        theTextField.returnKeyType = UIReturnKeyDone;
        theTextField.clearsOnBeginEditing = NO;
        theTextField.textAlignment = UITextAlignmentLeft;

        // (The tag by indexPath.row is the critical part to identifying the appropriate
        // row in textFieldDidBeginEditing and textFieldShouldEndEditing below:)

        theTextField.tag=indexPath.row;

        theTextField.delegate = self;

        theTextField.clearButtonMode = UITextFieldViewModeWhileEditing;
        [theTextField setEnabled: YES];

        [cell addSubview:theTextField];

        [theTextField release];

    }

    return cell;
}

-(void) textFieldDidBeginEditing:(UITextField *)textField {

    int z = textField.tag;                                              

    if (z > 4) {

        // Only deal with the table row if the row index is 5 
        // or greater since the first five rows are already 
        // visible above the keyboard   

        // resize the UITableView to fit above the keyboard

        self.wordsTableView.frame = CGRectMake(0.0,44.0,320.0,200.0);       

        // adjust the contentInset

        wordsTableView.contentInset = UIEdgeInsetsMake(0, 0, 0, 10);        

        // Scroll to the current text field

        [wordsTableView scrollToRowAtIndexPath:[NSIndexPath indexPathForRow:z inSection:0] atScrollPosition:UITableViewScrollPositionBottom animated:YES];

    }
}


- (BOOL)textFieldShouldEndEditing:(UITextField *)textField {

    // Determine which row is being edited

    int z = textField.tag;  

    if (z > 4) {

        // resize the UITableView to the original size

        self.wordsTableView.frame = CGRectMake(0.0,44.0,320.0,416.0);       

        // Undo the contentInset
        wordsTableView.contentInset = UIEdgeInsetsMake(0, 0, 0, 0);         

    }

    return YES;

}

- (BOOL)textFieldShouldReturn:(UITextField *)textField {

    // Dismisses the keyboard when the "Done" button is clicked

    [textField resignFirstResponder];

    return YES;                                 

}


I needed a simple solution so for me helped:

func textFieldShouldBeginEditing(_ textField: UITextField) -> Bool {
        let pointInTable = textField.superview!.convert(textField.frame.origin, to: tableView)
        var tableVContentOffset = tableView.contentOffset
        tableVContentOffset.y = pointInTable.y
        if let accessoryView = textField.inputAccessoryView {
            tableVContentOffset.y -= accessoryView.frame.size.height
        }
        tableView.setContentOffset(tableVContentOffset, animated: true)
        return true;
    }

Get UITableView to scroll to the selected UITextField and Avoid Being Hidden by Keyboard


Try my coding, this will help for ypu

tabelview.contentInset =  UIEdgeInsetsMake(0, 0, 210, 0);
[tableview scrollToRowAtIndexPath:[NSIndexPath indexPathForRow:your_indexnumber inSection:Your_section]
                 atScrollPosition:UITableViewScrollPositionMiddle animated:NO];


Apple has an official post explaining how to do this naturally as they do in the UITableViewController. My Stackoverflow answer has this explained along with a swift version.

https://stackoverflow.com/a/31869898/1032179


You need to resize the tableView itself so that it does not go under the keyboard.

-(void) textFieldDidBeginEditing:(UITextField *)textField {

// SUPPOSEDLY Scroll to the current text field
self.worldsTableView.frame = CGRectMake(//make the tableView smaller; to only be in the area above the keyboard);
CGRect textFieldRect = [textField frame];
[self.wordsTableView scrollRectToVisible:textFieldRect animated:YES];

}

Alternatively, you can use a keyboard notification; this works slightly better because you have more information, and is more consistent in terms of knowing when the keyboard is coming up:

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

And then implement:

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

}
- (void)keyboardWillHide:(NSNotification *)notification {

}


My code. Maybe someone will be useful: Custom textField cell in tableView

.m

    @property (nonatomic, strong) UITextField *currentCellTextField;

       CustomCell * cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier2];
            if (cell == nil) {
                NSArray * nib = [[NSBundle mainBundle] loadNibNamed:@"CustomCell" owner:self options:nil];
                cell = (CustomCell *)[nib objectAtIndex:0];
                cell.textfield.delegate = self;
            }
      - (void) textFieldDidBeginEditing:(UITextField *)textField
 {
  self.currentCellTextField = textField;

  CGPoint pnt = [self.organisationTableView convertPoint:textField.bounds.origin fromView:textField];
  NSIndexPath* path = [self.organisationTableView indexPathForRowAtPoint:pnt];

if (path.section >= 2) {
    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationDuration:0.3];
    self.organisationTableView.contentInset = UIEdgeInsetsMake(0, 0, kOFFSET_FOR_KEYBOARD, 0);
    CGPoint siize = self.organisationTableView.contentOffset;
    siize.y =(pnt.y-170);
    self.organisationTableView.contentOffset = CGPointMake(0, siize.y);
    [UIView commitAnimations];
    }
 }

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

CGPoint pnt = [self.organisationTableView convertPoint:textField.bounds.origin fromView:textField];
NSIndexPath* path = [self.organisationTableView indexPathForRowAtPoint:pnt];

 if (path.section >= 2) {
    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationDuration:0.3];
    self.organisationTableView.contentInset = UIEdgeInsetsZero;
    self.organisationTableView.contentOffset = CGPointMake(0, self.organisationTableView.contentOffset.y);
    [UIView commitAnimations];
      }

 return YES;
   }


In my case my UITableview was inside another UIView and that UIvie was in the main UIScrollview. So I used more general solution for those kind of problems. I simply found the Y coordinate of my cell in the specific UIScrollView and then scrolled to correct point:

-(void)textFieldDidBeginEditing:(UITextField *)textField{
float kbHeight = 216;//Hard Coded and will not support lanscape mode
UITableViewCell *cell = (UITableViewCell *)[textField superview];
float scrollToHeight = [self FindCordinate:cell];
[(UIScrollView *)self.view setContentOffset:CGPointMake(0, scrollToHeight - kbHeight + cell.frame.size.height) animated:YES];
}

-(float)FindCordinate:(UIView *)cell{
float Ycordinate = 0.0;
while ([cell superview] != self.view) {
    Ycordinate += cell.frame.origin.y;
    cell = [cell superview];
}
Ycordinate += cell.frame.origin.y;
return Ycordinate;
}


Another simple solution is adding an additional space for the footer of the last table section:

- (float)tableView:(UITableView *)tableView heightForFooterInSection:(NSInteger)section {
    if (section == lastSection) {
        return keyboard height;
    }
    return 0;
}

We can add our icon into this area as well. :)


You can try adding a UITableViewController to the UIViewController instead of just a table view. This way you can call UITableViewController's viewWillAppear and everything will appear to work.

Example:

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


I have add a little feature to @FunkyKat and @bmauter answers (great answer by the way, it should be the one accepted)

The regular Table View edge insets is preserved, before/after the keyboard apparition.

- (void)keyboardWillShow:(NSNotification *)sender
{
    CGSize kbSize = [[[sender userInfo] objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue].size;
    NSTimeInterval duration = [[[sender userInfo] objectForKey:UIKeyboardAnimationDurationUserInfoKey] doubleValue];

    CGFloat height = UIDeviceOrientationIsPortrait([[UIDevice currentDevice] orientation]) ? kbSize.width : kbSize.height;

    [UIView animateWithDuration:duration animations:^{
        UIEdgeInsets edgeInsets = self.tableView.contentInset;
        edgeInsets.bottom += height;
        self.tableView.contentInset = edgeInsets;
        edgeInsets = self.tableView.scrollIndicatorInsets;
        edgeInsets.bottom += height;
        self.tableView.scrollIndicatorInsets = edgeInsets;
    }];
}

- (void)keyboardWillHide:(NSNotification *)sender
{
    CGSize kbSize = [[[sender userInfo] objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue].size;
    NSTimeInterval duration = [[[sender userInfo] objectForKey:UIKeyboardAnimationDurationUserInfoKey] doubleValue];

    CGFloat height = UIDeviceOrientationIsPortrait([[UIDevice currentDevice] orientation]) ? kbSize.width : kbSize.height;

    [UIView animateWithDuration:duration animations:^{
        UIEdgeInsets edgeInsets = self.tableView.contentInset;
        edgeInsets.bottom -= height;
        self.tableView.contentInset = edgeInsets;
        edgeInsets = self.tableView.scrollIndicatorInsets;
        edgeInsets.bottom -= height;
        self.tableView.scrollIndicatorInsets = edgeInsets;
    }];
}
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