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How to lose margin/padding in UITextView

I have a UITextView in my iOS application, which displays a large amount of text.

I am then paging this text by using the offset margin parameter of the UITextView.

My problem is that the padding of the UITextView is confusing my calculations as it seems to be different depending on the font size and typeface that I use.

Is it possible to remove the padding surrounding the content of the UITextView?

Note that this QA is almost ten years old! With 100,000+ views, since it's one of the stupidest problems in iOS. Just FTR I put in the current, 2017, reasonably simple / usual / accepted solution below as an answer.
I still get updates on this, having written a hardcoded workaround in 2009 when IOS 3.0 had just been released. I just edited the answer to clearly state that it is years out of date and to ignore the accepted status.
Amazingly, well over ten years now (200,000 views of this QA!) and Apple still have not fixed the combination of plain bugs, soft bugs, and bizarre behavior in UITextView. It is really one of the weirdest things in all of mobile computing development!

P
Peter Mortensen

For iOS 7.0, I've found that the contentInset trick no longer works. This is the code I used to get rid of the margin/padding in iOS 7.

This brings the left edge of the text to the left edge of the container:

textView.textContainer.lineFragmentPadding = 0

This causes the top of the text to align with the top of the container:

textView.textContainerInset = .zero

Both lines are needed to completely remove the margin/padding.


This is working for me for two lines, but by the time I get to 5 lines, the text is getting cut off.
Note that the second line can also be written as: self.descriptionTextView.textContainerInset = UIEdgeInsetsZero;
Setting lineFragmentPadding to 0 is the magic I was looking for. I have no idea why Apple makes it so hard to line up UITextView content with other controls.
This is the correct answer. Scrolling horizontally doesn't happen with this solution.
lineFragmentPadding is not intended to modify margins. From the docs Line fragment padding is not designed to express text margins. Instead, you should use insets on your text view, adjust the paragraph margin attributes, or change the position of the text view within its superview.
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Peter Mortensen

Up-to-date for 2021

It is one of the silliest bugs in iOS.

The class given here, UITextViewFixed , is used widely, and is usually the most reasonable solution overall.

Here is the class:

@IBDesignable class UITextViewFixed: UITextView {
    override func layoutSubviews() {
        super.layoutSubviews()
        setup()
    }
    func setup() {
        textContainerInset = UIEdgeInsets.zero
        textContainer.lineFragmentPadding = 0
    }
}

Don't forget to turn off scrollEnabled in the Inspector!

The solution works properly in storyboard The solution works properly at runtime

That's it, you're done.

In general, that should be all you need in most cases.

Even if you are changing the height of the text view on the fly, UITextViewFixed usually does all you need.

(A common example of changing the height on the fly, is changing it as the user types.)

Here is the broken UITextView from Apple...

https://i.stack.imgur.com/4s7P6.png

Here is UITextViewFixed:

https://i.stack.imgur.com/MS5V4.png

Note that of course you must...

...turn off scrollEnabled in the Inspector!

(Turning on scrollEnabled means "make this view expand as much as possible vertically by expanding the bottom margin as much as possible.")

Some further issues

(1) In some very unusual cases dynamically changing heights, Apple does a bizarre thing: they add extra space at the bottom.

No, really! This would have to be one of the most infuriating things in iOS.

If you encounter the problem, here is a "quick fix" which usually helps:

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

        // this is not ideal, but sometimes this "quick fix"
        // will solve the "extra space at the bottom" insanity:
        var b = bounds
        let h = sizeThatFits(CGSize(
           width: bounds.size.width,
           height: CGFloat.greatestFiniteMagnitude)
       ).height
       b.size.height = h
       bounds = b
 ...

(2) In rare cases, to fix yet another subtle mess-up by Apple, you have to add:

override func setContentOffset(_ contentOffset: CGPoint, animated: Bool) {
    super.setContentOffset(contentOffset, animated: false) // sic
}

(3) Arguably, we should be adding:

contentInset = UIEdgeInsets.zero

just after .lineFragmentPadding = 0 in UITextViewFixed.

However ... believe or not ... that just doesn't work in current iOS! (Checked 2021.) It may be necessary to add that line in the future.

The fact that UITextView is broken in iOS is one of the weirdest things in all of mobile computing. Ten year anniversary of this question and it's still not fixed!

Finally, here's a somewhat similar tip for TextField: Set the maximum character length of a UITextField in Swift

Completely random tip: how to add the "..." on the end

Often you are using a UITextView "like a UILabel". So you want it to truncate text using an ellipsis, "..."

If so, add:

 textContainer.lineBreakMode = .byTruncatingTail

Handy tip if you want zero height, when, there's no text at all

Often you use a text view to only display text. So, you use lines "0" to mean the text view will automatically change height depending on how many lines of text.

That's great. But if there is no text at all, then unfortunately you get the same height as if there is one line of text!!!! The text view never "goes away".

https://i.stack.imgur.com/rPM5y.png

If you want it to "go away", just add this

override var intrinsicContentSize: CGSize {
    var i = super.intrinsicContentSize
    print("for \(text) size will be \(i)")
    if text == "" { i.height = 1.0 }
    print("   but we changed it to \(i)")
    return i
}

https://i.stack.imgur.com/od7BI.png

(I made it '1' height, so it's clear what's going on in that demo, '0' is fine.)

What about UILabel?

When just displaying text, UILabel has many advantages over UITextView. UILabel does not suffer from the problems described on this Q&A page.

Indeed the reason we all usually "give up" and just use UITextView is that UILabel is difficult to work with. In particular it is ridiculously difficult to just add padding, correctly, to UILabel.

In fact here is a full discussion on how to "finally" correctly add padding to UILabel: Adding space/padding to a UILabel. In some cases if you are doing a difficult layout with dynamic height cells, it is sometimes better to do it the hard way with UILabel.


Why do you say it's necessary to turn off scrollEnabled in the inspector? When I do that I seem to get even less space in the my text view.
The height of the frame of the scroll view is unrelated to the content size. The question posed by OP makes no mention of height. Simply trying to understand your response.
I've posted an updated answer to @Fattie's answer which helped me to really get rid of all insets using the special trick of enabling/disabling translatesAutoresizingMaskIntoConstraints. With this answer alone I was not able to remove all the margins (some strange bottom margin resisted to go away) in a view hierarchy using auto layout. It also deals with calculation of view sizes using systemLayoutSizeFitting, which previously returned an invalid size due to the buggy UITextView
I had textviews in table, the ones that had single line of text didn't calculate its height correctly (autolayout). To fix it I had to override didMoveToSuperview and call setup there also.
I used this in my app and it causes a recursive call between layoutSubviews and setup causing a stack overflow error! Something is wrong here
P
Peter Mortensen

This workaround was written in 2009 when iOS 3.0 was released. It no longer applies.

I ran into the exact same problem, and in the end I had to wind up using

nameField.contentInset = UIEdgeInsetsMake(-4, -8, 0, 0);

where nameField is a UITextView. The font I happened to be using was Helvetica 16 point. It’s only a custom solution for the particular field size I was drawing. This makes the left offset flush with the left side, and the top offset where I want it for the box it’s drawn in.

In addition, this only seems to apply to UITextViews where you are using the default aligment, i.e.,

nameField.textAlignment = NSTextAlignmentLeft;

Align to the right for example and the UIEdgeInsetsMake seems to have no impact on the right edge at all.

At very least, using the .contentInset property allows you to place your fields with the "correct" positions, and accommodate the deviations without offsetting your UITextViews.


Yes it does work in iOS 7. Make sure the UIEdgeInset is set to the right values. It might be different than UIEdgeInsetsMake(-4,-8,0,0).
In IOS 7 I found UIEdgeInsetsMake(0,-4,0,-4) worked the best.
Yes, those are example numbers. I stated "Its only a custom solution for the particular field size I was drawing". Mainly I was trying to illustrate that you have to play with the numbers for your unique layout situation.
UITextAlignmentLeft is deprecated in iOS 7. Use NSTextAlignmentLeft.
I don't get why people upvote an answer that utilizes hard-coded values. It is VERY likely to break in future versions of iOS and is just a plain bad idea.
p
pkamb

Building off some of the good answers already given, here is a purely Storyboard / Interface Builder-based solution that works in iOS 7.0+

Set the UITextView's User Defined Runtime Attributes for the following keys:

textContainer.lineFragmentPadding
textContainerInset

https://i.stack.imgur.com/2VzYp.png


This is clearly the best answer, especially if you need a XIB-only solution
Copy/paste: textContainer.lineFragmentPadding | textContainerInset
This is what makes a beautiful answer - easy and works well, even after 3 years :)
E
Engin Kurutepe

On iOS 5 UIEdgeInsetsMake(-8,-8,-8,-8); seems to work great.


P
Peter Mortensen

I would definitely avoid any answers involving hard-coded values, as the actual margins may change with user font-size settings, etc.

Here is user1687195's answer, written without modifying the textContainer.lineFragmentPadding (because the documentation state this is not the intended usage).

This works great for iOS 7 and later.

self.textView.textContainerInset = UIEdgeInsetsMake(
                                      0,
                                      -self.textView.textContainer.lineFragmentPadding,
                                      0,
                                      -self.textView.textContainer.lineFragmentPadding);

This is effectively the same outcome, just a bit cleaner in that it doesn't misuse the lineFragmentPadding property.


I tried another solution based on this answer and it works great. The solutions is: self.textView.textContainer.lineFragmentPadding = 0;
@BakytAbdrasulov please read my answer. While your solution works, it is not in accordance with the docs (see the link in my answer). lineFragmentPadding isn't meant to control the margins. That's why you're supposed to use textContainerInset.
P
Peter Mortensen

Storyboard or Interface Builder solution using user-defined runtime attributes:

Screenshots are of iOS 7.1 & iOS 6.1 with contentInset = {{-10, -5}, {0, 0}}.

https://i.stack.imgur.com/rDBdL.png

https://i.stack.imgur.com/z0HXK.png


Worked for me in iOS 7.
Up just for user defined runtime attributes - awesome!
m
mikeho

All these answers address the title question, but I wanted to propose some solutions for the problems presented in the body of the OP's question.

Size of Text Content

A quick way to calculate the size of the text inside the UITextView is to use the NSLayoutManager:

UITextView *textView;
CGSize textSize = [textView usedRectForTextContainer:textView.textContainer].size;

This gives the total scrollable content, which may be bigger than the UITextView's frame. I found this to be much more accurate than textView.contentSize since it actually calculates how much space the text takes up. For example, given an empty UITextView:

textView.frame.size = (width=246, height=50)
textSize = (width=10, height=16.701999999999998)
textView.contentSize = (width=246, height=33)
textView.textContainerInset = (top=8, left=0, bottom=8, right=0)

Line Height

UIFont has a property that quickly allows you to get the line height for the given font. So you can quickly find the line height of the text in your UITextView with:

UITextView *textView;
CGFloat lineHeight = textView.font.lineHeight;

Calculating Visible Text Size

Determining the amount of text that is actually visible is important for handling a "paging" effect. UITextView has a property called textContainerInset which actually is a margin between the actual UITextView.frame and the text itself. To calculate the real height of the visible frame you can perform the following calculations:

UITextView *textView;
CGFloat textViewHeight = textView.frame.size.height;
UIEdgeInsets textInsets = textView.textContainerInset;
CGFloat textHeight = textViewHeight - textInsets.top - textInsets.bottom;

Determining Paging Size

Lastly, now that you have the visible text size and the content, you can quickly determine what your offsets should be by subtracting the textHeight from the textSize:

// where n is the page number you want
CGFloat pageOffsetY = textSize - textHeight * (n - 1);
textView.contentOffset = CGPointMake(textView.contentOffset.x, pageOffsetY);

// examples
CGFloat page1Offset = 0;
CGFloat page2Offset = textSize - textHeight
CGFloat page3Offset = textSize - textHeight * 2

Using all of these methods, I didn't touch my insets and I was able to go to the caret or wherever in the text that I want.


P
Peter Mortensen

You can use the textContainerInset property of UITextView:

textView.textContainerInset = UIEdgeInsetsMake(10, 10, 10, 10);

(top, left, bottom, right)


I wonder why this is not assigned as the best answer here. The textContainerInset really satisfied my needs.
Updating the bottom value on the textContainerInset property isn't working for me when I want to change it to a new value—see stackoverflow.com/questions/19422578/….
@MaggiePhillips It's not the best answer because hardcoded values can't possibly be the right way to do this, and are guaranteed to fail in some cases. You need to take lineFragmentPadding into account.
P
Peter Mortensen

Here is an updated version of Fattie's very helpful answer. It added two important lines that helped me get the layout working on iOS 10 and 11 (and probably on lower ones, too):

@IBDesignable class UITextViewFixed: UITextView {
    override func layoutSubviews() {
        super.layoutSubviews()
        setup()
    }
    func setup() {
        translatesAutoresizingMaskIntoConstraints = true
        textContainerInset = UIEdgeInsets.zero
        textContainer.lineFragmentPadding = 0
        translatesAutoresizingMaskIntoConstraints = false
    }
}

The important lines are the two translatesAutoresizingMaskIntoConstraints = <true/false> statements!

This surprisingly removes all margins in all my circumstances!

While the textView is not the first responder, it could happen that there is some strange bottom margin that could not be solved using the sizeThatFits method that is mentioned in the accepted answer.

When tapping into the textView, suddenly the strange bottom margin disappeared and everything looked like it should, but only as soon as the textView has got firstResponder.

So I read here on Stack Overflow that enabling and disabling translatesAutoresizingMaskIntoConstraints does help when setting the frame/bounds manually in between the calls.

Fortunately this not only works with frame setting, but with the two lines of setup() sandwiched between the two translatesAutoresizingMaskIntoConstraints calls!

This, for example, is very helpful when calculating the frame of a view using systemLayoutSizeFitting on a UIView. It gives back the correct size (which previously it didn't)!

As in the original answer mentioned:

Don't forget to turn off scrollEnabled in the Inspector! That solution does work properly in storyboard, as well as at runtime.

That's it, and now you're really done!


A
Anson Yao

For iOS 10, the following line works for the top and bottom padding removing.

captionTextView.textContainerInset = UIEdgeInsetsMake(0, 0, 0, 0)

Xcode 8.2.1. still the same issue as mentioned in this answer. My solution was to edit the values as UIEdgeInsets(top: 0, left: -4.0, bottom: 0, right: -4.0).
UIEdgeInset.zero works using XCode 8.3 and iOS 10.3 Simulator
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Pang

Latest Swift:

self.textView.textContainerInset = .init(top: -2, left: 0, bottom: 0, right: 0)
self.textView.textContainer.lineFragmentPadding = 0

Great answer. This answer removes the additional Top inset. textView.textContainerInset = UIEdgeInsets.zero doesn't remove 2 pixels from top inset.
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Peter Mortensen

For Swift 4, Xcode 9

Use the following function. It can change the margin/padding of the text in UITextView:

public func UIEdgeInsetsMake(_ top: CGFloat, _ left: CGFloat, _ bottom: CGFloat, _ right: CGFloat) -> UIEdgeInsets

So in this case it is:

 self.textView?.textContainerInset = UIEdgeInsetsMake(0, 0, 0, 0)

N
N S

Here's an easy little extension that will remove Apple's default margin from every text view in your app.

Note: Interface Builder will still show the old margin, but your app will work as expected.

extension UITextView {

   open override func awakeFromNib() {
      super.awakeFromNib();
      removeMargins();
   }

   /** Removes the Apple textview margins. */
   public func removeMargins() {
      self.contentInset = UIEdgeInsetsMake(
         0, -textContainer.lineFragmentPadding,
         0, -textContainer.lineFragmentPadding);
   }
}

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Peter Mortensen

Doing the inset solution I still had padding on the right side and the bottom. Also text alignment was causing issues. The only sure-fire way I found was to put the text view inside another view that is clipped to bounds.


What is the "inset solution"? Can you elaborate and/or add a reference? Please respond by editing (changing) your answer, not here in comments (without "Edit:", "Update:", or similar - the answer should appear as if it was written today).
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Peter Mortensen

For SwiftUI

If you are making your own TextView using UIViewRepresentable and want to control the padding, in your makeUIView function, simply do:

uiTextView.textContainerInset = UIEdgeInsets(top: 10, left: 18, bottom: 0, right: 18)

or whatever you want.


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Peter Mortensen

For me (iOS 11 & Xcode 9.4.1) what worked magically was setting up textView.font property to UIFont.preferred(forTextStyle:UIFontTextStyle) style and also the first answer as mentioned by Fattie. But the Fattie answer did not work till I set the textView.font property. Else UITextView keeps behaving erratically.


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Peter Mortensen

In case anyone is looking for the latest Swift version then the below code is working fine with Xcode 10.2 and Swift 4.2

yourTextView.textContainerInset = UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 0)

A
Alex

The textView scrolling also affect the position of the text and make it look like not vertically centered. I managed to center the text in the view by disabling the scrolling and setting the top inset to 0:

    textView.scrollEnabled = NO;
    textView.textContainerInset = UIEdgeInsetsMake(0, textView.textContainerInset.left, textView.textContainerInset.bottom, textView.textContainerInset.right);

For some reason I haven't figured it out yet, the cursor is still not centered before the typing begins, but the text centers immediately as I start typing.


m
mert kutluca

You need to set inset and lineFragmentPadding on didMoveToSuperView

@IBDesignable class UITextViewFixed: UITextView {
    override func didMoveToSuperview() {
        super.didMoveToSuperview()
        setup()
    }
    func setup() {
        textContainerInset = UIEdgeInsets.zero
        textContainer.lineFragmentPadding = 0
    }
}

Is it textContainerInset? Not textContainer.Inset?
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Peter Mortensen

I have found one more approach. Getting the view with text from UITextView's subviews and setting it up in the layoutSubview method of a subclass:

- (void)layoutSubviews {
    [super layoutSubviews];

    const int textViewIndex = 1;
    UIView *textView = [self.subviews objectAtIndex:textViewIndex];
    textView.frame = CGRectMake(
                                 kStatusViewContentOffset,
                                 0.0f,
                                 self.bounds.size.width - (2.0f * kStatusViewContentOffset),
                                 self.bounds.size.height - kStatusViewContentOffset);
}

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Peter Mortensen

In case you want to set an HTML string and avoid the bottom padding, please make sure that you are not using block tags, i.e., div and p.

In my case this was the reason. You can easily test it out by replacing occurrences of block tags with, e.g., the span tag.


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Peter Mortensen

For anyone coming to this because of parsing HTML into UITextView, just remove the new line introduced by the closing p tag "/n". I assume that you work with NSMutableAttributedString:

if let lastCharacter = attributedString.string.last, lastCharacter == "\n" {
    attributedString.deleteCharacters(in: NSRange(location:(attributedString.length) - 1, length:1))
}

L
Luke
[firstNameTextField setContentVerticalAlignment:UIControlContentVerticalAlignmentCenter];

An explanation would be in order. E.g., what is the idea/gist? Please respond by editing (changing) your answer, not here in comments (without "Edit:", "Update:", or similar - the answer should appear as if it was written today).