How to calculate TextView height base on text

Question

I am using the code below for calculate the height of text, then set this height for UILabel and UITextView

CGSize targetSize = CGSizeMake(300, CGFLOAT_MAX);
NSString *message = @"The Internet connection appears to be offline.";

NSStringDrawingContext *context = [[NSStringDrawingContext alloc] init];
CGSize boundingBox = [message boundingRectWithSize:targetSize
                                              options:NSStringDrawingUsesLineFragmentOrigin
                                           attributes:@{NSFontAttributeName:FontOpenSanWithSize(14)}
                                              context:context].size;

CGSize size = CGSizeMake(ceil(boundingBox.width), ceil(boundingBox.height));
// it will return size:width = 299 and size height 20
// => if I use this height and set for UILabel, it can display full content
// => if I use this height and set for UITextView, it can not display full content

It's work perfect for UILabel but for UITextView sometime it calculate wrong.
I think the problem happened because the padding (left, right) of UITextView is bigger than UILabel.
So how can I calculate the correct size of text for display in UITextView. Any help or suggestion would be great appreciated.

Like the description image below
With the same size (300), same font, same text but the UITextView display in 2 lines, but UILabel in 1 lines. And my code for calculate height return 20, it not enough for display in 2 lines, so the UITextViewcan not display full content

The reason why I need to calculate the height of UITextView base on text because my UITextView is in a popup. And the popup height will depend on the TextView height

you can bind textview height constant and then use it to update height i guess — Anjali Bhimani, Sep 01 '16 at 10:07
Just visit here http://stackoverflow.com/questions/31678779/how-to-dynamically-change-the-textview-height-and-cell-height-according-to-the-t — Sailendra, Sep 01 '16 at 10:09
Possible duplicate of [How do I size a UITextView to its content?](http://stackoverflow.com/questions/50467/how-do-i-size-a-uitextview-to-its-content) — Sanoj Kashyap, Sep 01 '16 at 10:20
check this http://stackoverflow.com/questions/50467/how-do-i-size-a-uitextview-to-its-content — Sanoj Kashyap, Sep 01 '16 at 10:20

score 12 · Answer 1 · answered Sep 01 '16 at 12:34

There are two things you can try:

Set textView.textContainerInset = UIEdgeInsetsZero
Set textView.textContainer.lineFragmentPadding = 0

With these operations you can get rid of all the padding in the textView and when its width matches with the label's one the heights are also the same.

Here's a sample code you can place in an empty viewController and test it yourself:

- (void)viewDidAppear:(BOOL)animated {
    [super viewDidAppear:animated];

    NSString *text = @"The internet connection appears to be offline.";
    CGFloat width = 100.f;

    UITextView *textView = [[UITextView alloc] initWithFrame:CGRectMake(20, 20, width, 300)];
    textView.font = [UIFont fontWithName:@"AvenirNext-Regular" size:12.f];
    textView.text = text;
    [self.view addSubview:textView];

    UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(20 + width, 20, width, 300)];
    label.numberOfLines = 0;
    label.font = [UIFont fontWithName:@"AvenirNext-Regular" size:12.f];
    label.text = text;
    [self.view addSubview:label];

    // Getting rid of textView's padding
    textView.textContainerInset = UIEdgeInsetsZero;
    textView.textContainer.lineFragmentPadding = 0;

    // Setting height of textView to its contentSize.height
    CGRect textViewFrame = textView.frame;
    textViewFrame.size = textView.contentSize;
    textView.frame = textViewFrame;

    // Setting height of label accorting to it contents and width
    CGRect labelFrame = label.frame;
    labelFrame.size = [label sizeThatFits:CGSizeMake(width, HUGE_VALF)];
    labelFrame.size.width = width;
    label.frame = labelFrame;

    NSLog(@"Label bounds: %@", NSStringFromCGRect(label.bounds));
    NSLog(@"TextView bounds: %@", NSStringFromCGRect(textView.bounds));

    // Visualizing final effect with borders
    textView.layer.borderColor = [UIColor redColor].CGColor;
    textView.layer.borderWidth = 1.f;
    label.layer.borderColor = [UIColor greenColor].CGColor;
    label.layer.borderWidth = 1.f;
}

Console output:

2016-09-01 14:29:06.118 stack39268477[943:243243] Label bounds: {{0, 0}, {100, 66}}
2016-09-01 14:29:06.119 stack39268477[943:243243] TextView bounds: {{0, 0}, {100, 66}}

score 11 · Answer 2 · edited Sep 01 '16 at 10:25

11

You don't need to calculate Height of UITextview based on text.

Just change frame and set height like this:

textview.size.height = textview.contentSize.height;

This is easy solution. I hope this helps you.

edited Sep 01 '16 at 10:25

Marco Santarossa

4,058
1
29
49

answered Sep 01 '16 at 10:18

Nimisha Ranipa

8,304
2
14
29

my case is different so I can not use this way. please check my update – Linh Sep 01 '16 at 10:27

score 6 · Answer 3 · answered Nov 26 '17 at 09:04

This calculates the size of any string, whether or not you put them in a text view.

let frame = NSString(string: yourText).boundingRect(
    with: CGSize(width: yourDesiredWidth, height: .infinity),
    options: [.usesFontLeading, .usesLineFragmentOrigin],
    attributes: [.font : yourFont],
    context: nil)

let height = frame.size.height

score 4 · Answer 4 · answered Mar 12 '18 at 17:26

Most of the answers here are hints into the right direction :-)

So, just to sum it all up...

UITextView uses a NSTextContainer (inside a private API _UITextContainerView) to do the real layout work. This NSTextContainer(View) may have insets to the surrounding UITextView, which are set by UITextView's textContainerInset property. The defaults for this insets seem to be:

top: 8
left: 0
bottom: 8
right: 0

The NSTextContainer itself may have additional left and right insets for the text itself. These insets are set in NSTextContainer's lineFragmentPadding property.

The default for this is 5.0.

As a result, when calculating the optimum frame size for a UITextView based on the boundingRect for some text inside that UITextView, we have to take all these insets into account:

CGSize reservedSpace = CGSizeMake((textView.textContainerInset.left + (2.0 * textView.textContainer.lineFragmentPadding) + textView.textContainerInset.right),
                                  (textView.textContainerInset.top + textView.textContainerInset.bottom));
CGSize targetSize = CGSizeMake((300.0 - reservedSpace.width), CGFLOAT_MAX);
NSString* message = @"The Internet connection appears to be offline.";

NSStringDrawingContext* context = [[NSStringDrawingContext alloc] init];
CGSize boundingBox = [message boundingRectWithSize:targetSize
                                              options:NSStringDrawingUsesLineFragmentOrigin
                                           attributes:@{NSFontAttributeName:FontOpenSanWithSize(14)}
                                              context:context].size;

CGSize size = CGSizeMake(ceil(boundingBox.width),
                         (ceil(boundingBox.height) + reservedSpace.height));

Good luck :-)

score 3 · Answer 5 · answered May 04 '20 at 21:09

Swift 5

A classic hack I've used to do this is create a function that takes the String as a parameter. Within the function it generates a label with the width required, infinite number of lines, and a height of "too much". Then apply sizeToFit() on the label and return the height of the frame.

func calculatedHeight(for text: String, width: CGFloat) -> CGFloat {
    let label = UILabel(frame: CGRect(x: 0, y: 0, width: width,
                                      height: .greatestFiniteMagnitude))
    label.numberOfLines = 0
    label.text = text
    label.sizeToFit()
    return label.frame.height
}

The returned height can be applied to a UITextField height anchor. Though I do recommend calculating the width dynamically based on screen size, but that's up to you.

score -1 · Answer 6 · answered Dec 20 '17 at 07:53

self.textView.textContainerInset = UIEdgeInsets.zero self.textView.textContainer.lineFragmentPadding = 0

In storyboard or xib mark textview height >=0.

If you are using text view with table view. Calculate cell height according to content, textview will adjust it's space.

How to calculate TextView height base on text

6 Answers6

Linked