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UITableViewCell with UITextView height in iOS 7?

First of all, it is very important to note, that there is a big difference between UITextView and UILabel when it comes to how text is rendered. Not only does UITextView have insets on all borders, but also the text layout inside it is slightly different.

Therefore, sizeWithFont: is a bad way to go for UITextViews.

Instead UITextView itself has a function called sizeThatFits: which will return the smallest size needed to display all contents of the UITextView inside a bounding box, that you can specify.

The following will work equally for both iOS 7 and older versions and as of right now does not include any methods, that are deprecated.


Simple Solution

- (CGFloat)textViewHeightForAttributedText: (NSAttributedString*)text andWidth: (CGFloat)width {
    UITextView *calculationView = [[UITextView alloc] init];
    [calculationView setAttributedText:text];
    CGSize size = [calculationView sizeThatFits:CGSizeMake(width, FLT_MAX)];
    return size.height;
}

This function will take a NSAttributedString and the desired width as a CGFloat and return the height needed


Detailed Solution

Since I have recently done something similar, I thought I would also share some solutions to the connected Issues I encountered. I hope it will help somebody.

This is far more in depth and will cover the following:

  • Of course: setting the height of a UITableViewCell based on the size needed to display the full contents of a contained UITextView
  • Respond to text changes (and animate the height changes of the row)
  • Keeping the cursor inside the visible area and keeping first responder on the UITextView when resizing the UITableViewCell while editing

If you are working with a static table view or you only have a known number of UITextViews, you can potentially make step 2 much simpler.

1. First, overwrite the heightForRowAtIndexPath:

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath {
    // check here, if it is one of the cells, that needs to be resized
    // to the size of the contained UITextView
    if (  )             
        return [self textViewHeightForRowAtIndexPath:indexPath];
    else
    // return your normal height here:
            return 100.0;           
}

2. Define the function that calculated the needed height:

Add an NSMutableDictionary (in this example called textViews) as an instance variable to your UITableViewController subclass.

Use this dictionary to store references to the individual UITextViews like so:

(and yes, indexPaths are valid keys for dictionaries)

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *CellIdentifier = @"Cell";
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];
    
    // Do you cell configuring ...

    [textViews setObject:cell.textView forKey:indexPath];
    [cell.textView setDelegate: self]; // Needed for step 3

    return cell;
}

This function will now calculate the actual height:

- (CGFloat)textViewHeightForRowAtIndexPath: (NSIndexPath*)indexPath {
    UITextView *calculationView = [textViews objectForKey: indexPath];
    CGFloat textViewWidth = calculationView.frame.size.width;
    if (!calculationView.attributedText) {
        // This will be needed on load, when the text view is not inited yet
        
        calculationView = [[UITextView alloc] init];
        calculationView.attributedText = // get the text from your datasource add attributes and insert here
        textViewWidth = 290.0; // Insert the width of your UITextViews or include calculations to set it accordingly
    }
    CGSize size = [calculationView sizeThatFits:CGSizeMake(textViewWidth, FLT_MAX)];
    return size.height;
}

3. Enable Resizing while Editing

For the next two functions, it is important, that the delegate of the UITextViews is set to your UITableViewController. If you need something else as the delegate, you can work around it by making the relevant calls from there or using the appropriate NSNotificationCenter hooks.

- (void)textViewDidChange:(UITextView *)textView {

    [self.tableView beginUpdates]; // This will cause an animated update of
    [self.tableView endUpdates];   // the height of your UITableViewCell

    // If the UITextView is not automatically resized (e.g. through autolayout 
    // constraints), resize it here

    [self scrollToCursorForTextView:textView]; // OPTIONAL: Follow cursor
}

4. Follow cursor while Editing

- (void)textViewDidBeginEditing:(UITextView *)textView {
    [self scrollToCursorForTextView:textView];
}

This will make the UITableView scroll to the position of the cursor, if it is not inside the visible Rect of the UITableView:

- (void)scrollToCursorForTextView: (UITextView*)textView {
    
    CGRect cursorRect = [textView caretRectForPosition:textView.selectedTextRange.start];
    
    cursorRect = [self.tableView convertRect:cursorRect fromView:textView];
    
    if (![self rectVisible:cursorRect]) {
        cursorRect.size.height += 8; // To add some space underneath the cursor
        [self.tableView scrollRectToVisible:cursorRect animated:YES];
    }
}

5. Adjust visible rect, by setting insets

While editing, parts of your UITableView may be covered by the Keyboard. If the tableviews insets are not adjusted, scrollToCursorForTextView: will not be able to scroll to your cursor, if it is at the bottom of the tableview.

- (void)keyboardWillShow:(NSNotification*)aNotification {
    NSDictionary* info = [aNotification userInfo];
    CGSize kbSize = [[info objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;
    
    UIEdgeInsets contentInsets = UIEdgeInsetsMake(self.tableView.contentInset.top, 0.0, kbSize.height, 0.0);
    self.tableView.contentInset = contentInsets;
    self.tableView.scrollIndicatorInsets = contentInsets;
}

- (void)keyboardWillHide:(NSNotification*)aNotification {
    [UIView beginAnimations:nil context:nil];
    [UIView setAnimationDuration:0.35];
    UIEdgeInsets contentInsets = UIEdgeInsetsMake(self.tableView.contentInset.top, 0.0, 0.0, 0.0);
    self.tableView.contentInset = contentInsets;
    self.tableView.scrollIndicatorInsets = contentInsets;
    [UIView commitAnimations];
}

And last part:

Inside your view did load, sign up for the Notifications for Keyboard changes through NSNotificationCenter:

- (void)viewDidLoad
{
    [super viewDidLoad];

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

Please don't get mad at me, for making this answer so long. While not all of it is needed to answer the question, I believe that there are other people who these directly related issues will be helpful to.


UPDATE:

As Dave Haupert pointed out, I forgot to include the rectVisible function:

- (BOOL)rectVisible: (CGRect)rect {
    CGRect visibleRect;
    visibleRect.origin = self.tableView.contentOffset;
    visibleRect.origin.y += self.tableView.contentInset.top;
    visibleRect.size = self.tableView.bounds.size;
    visibleRect.size.height -= self.tableView.contentInset.top + self.tableView.contentInset.bottom;
    
    return CGRectContainsRect(visibleRect, rect);
}

Also I noticed, that scrollToCursorForTextView: still included a direct reference to one of the TextFields in my project. If you have a problem with bodyTextView not being found, check the updated version of the function.


There is a new function to replace sizeWithFont, which is boundingRectWithSize.

I added the following function to my project, which makes use of the new function on iOS7 and the old one on iOS lower than 7. It has basically the same syntax as sizeWithFont:

    -(CGSize)text:(NSString*)text sizeWithFont:(UIFont*)font constrainedToSize:(CGSize)size{
        if(IOS_NEWER_OR_EQUAL_TO_7){
            NSDictionary *attributesDictionary = [NSDictionary dictionaryWithObjectsAndKeys:
                                              font, NSFontAttributeName,
                                              nil];

            CGRect frame = [text boundingRectWithSize:size
                                              options:(NSStringDrawingUsesLineFragmentOrigin | NSStringDrawingUsesFontLeading)
                                           attributes:attributesDictionary
                                              context:nil];

            return frame.size;
        }else{
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wdeprecated-declarations"
            return [text sizeWithFont:font constrainedToSize:size];
#pragma clang diagnostic pop
        }
    }

You can add that IOS_NEWER_OR_EQUAL_TO_7 on your prefix.pch file in your project as:

#define IOS_NEWER_OR_EQUAL_TO_7 ( [ [ [ UIDevice currentDevice ] systemVersion ] floatValue ] >= 7.0 )

If you're using UITableViewAutomaticDimension I have a really simple (iOS 8 only) solution. In my case it's a static table view, but i guess you could adapt this for dynamic prototypes...

I have a constraint outlet for the text-view's height and I have implemented the following methods like this:

// Outlets

@property (weak, nonatomic) IBOutlet UITextView *textView;
@property (weak, nonatomic) IBOutlet NSLayoutConstraint *textViewHeight;


// Implementation

#pragma mark - Private Methods

- (void)updateTextViewHeight {
    self.textViewHeight.constant = self.textView.contentSize.height + self.textView.contentInset.top + self.textView.contentInset.bottom;
}

#pragma mark - View Controller Overrides

- (void)viewDidLoad {
    [super viewDidLoad];
    [self updateTextViewHeight];
}

#pragma mark - TableView Delegate & Datasource

- (CGFloat)tableView:(UITableView *)tableView estimatedHeightForRowAtIndexPath:(NSIndexPath *)indexPath {
    return 80;
}

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath {
    return UITableViewAutomaticDimension;
}

#pragma mark - TextViewDelegate

- (void)textViewDidChange:(UITextView *)textView {
    [self.tableView beginUpdates];
    [self updateTextViewHeight];
    [self.tableView endUpdates];
}

But remember: the text view must be scrollable, and you must setup your constraints such that they work for automatic dimension:

  • setup all the view in the cell in relation to each other, with fixed heights (including the text view height, which you will change programatically)
  • the top most view has the top spacing and the bottom most view has the bottom spacing to the super view;

The most basic cell example is:

  • no other views in the cell except the textview
  • 0 margins around all sides of the text view and a predefined height constraint for the text view.

Tim Bodeit's answer is great. I used the code of Simple Solution to correctly get the height of the text view, and use that height in heightForRowAtIndexPath. But I don't use the rest of the answer to resize the text view. Instead, I write code to change the frame of text view in cellForRowAtIndexPath.

Everything is working in iOS 6 and below, but in iOS 7 the text in text view cannot be fully shown even though the frame of text view is indeed resized. (I'm not using Auto Layout). It should be the reason that in iOS 7 there's TextKit and the position of the text is controlled by NSTextContainer in UITextView. So in my case I need to add a line to set the someTextView in order to make it work correctly in iOS 7.

    if (SYSTEM_VERSION_GREATER_THAN_OR_EQUAL_TO(@"7.0")) {
        someTextView.textContainer.heightTracksTextView = YES;
    }

As the documentation said, what that property does is:

Controls whether the receiver adjusts the height of its bounding rectangle when its text view is resized. Default value: NO.

If leave it with the default value, after resize the frame of someTextView, the size of the textContainer is not changed, leading to the result that the text can only be displayed in the area before resizing.

And maybe it is needed to set the scrollEnabled = NO in case there's more than one textContainer, so that the text will reflow from one textContainer to the another.


Here is one more solution that aims at simplicity and quick prototyping:

Setup:

  1. Table with prototype cells.
  2. Each cell contains dynamic sized UITextView w/ other contents.
  3. Prototype cells are associated with TableCell.h.
  4. UITableView is associated with TableViewController.h.

Solution:

(1) Add to TableViewController.m:

 // This is the method that determines the height of each cell.  
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath 
{
    // I am using a helper method here to get the text at a given cell.
    NSString *text = [self getTextAtIndex:indexPath];

    // Getting the height needed by the dynamic text view.
    CGSize size = [self frameForText:text sizeWithFont:nil constrainedToSize:CGSizeMake(300.f, CGFLOAT_MAX)];

    // Return the size of the current row.
    // 80 is the minimum height! Update accordingly - or else, cells are going to be too thin.
    return size.height + 80; 
}

// Think of this as some utility function that given text, calculates how much 
// space would be needed to fit that text.
- (CGSize)frameForText:(NSString *)text sizeWithFont:(UIFont *)font constrainedToSize:(CGSize)size
{
    NSDictionary *attributesDictionary = [NSDictionary dictionaryWithObjectsAndKeys:
                                          font, NSFontAttributeName,
                                          nil];
    CGRect frame = [text boundingRectWithSize:size
                                      options:(NSStringDrawingUsesLineFragmentOrigin | NSStringDrawingUsesFontLeading)
                                   attributes:attributesDictionary
                                      context:nil];

    // This contains both height and width, but we really care about height.
    return frame.size;
}

// Think of this as a source for the text to be rendered in the text view. 
// I used a dictionary to map indexPath to some dynamically fetched text.
- (NSString *) getTextAtIndex: (NSIndexPath *) indexPath
{
    return @"This is stubbed text - update it to return the text of the text view.";
}

(2) Add to TableCell.m:

// This method will be called when the cell is initialized from the storyboard
// prototype. 
- (void)awakeFromNib
{
    // Assuming TextView here is the text view in the cell. 
    TextView.scrollEnabled = YES;
}

Explanation:

So what's happening here is this: each text view is bound to the height of the table cells by vertical and horizontal constraints - that means when the table cell height increases, the text view increases its size as well. I used a modified version of @manecosta's code to calculate the required height of a text view to fit the given text in a cell. So that means given a text with X number of characters, frameForText: will return a size which will have a property size.height that matches the text view's required height.

Now, all that remains is the update the cell's height to match the required text view's height. And this is achieved at heightForRowAtIndexPath:. As noted in the comments, since size.height is only the height for the text view and not the entire cell, there should be some offset added to it. In the case of the example, this value was 80.


One approach if you're using autolayout is to let the autolayout engine calculate the size for you. This isn't the most efficient approach but it is pretty convenient (and arguably the most accurate). It becomes more convenient as the complexity of the cell layout grows - e.g. suddenly you have two or more textviews/fields in the cell.

I answered a similar question with a complete sample for sizing tableview cells using auto layout, here:

How to resize superview to fit all subviews with autolayout?