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Autolayout - intrinsic size of UIButton does not include title insets

If I have a UIButton arranged using autolayout, its size adjusts nicely to fit its content.

If I set an image as button.image, the instrinsic size again seems to account for this.

However, if I tweak the titleEdgeInsets of the button, the layout does not account for this and instead truncates the button title.

How can I ensure that the intrinsic width of the button accounts for the inset?

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

Edit:

I am using the following:

[self.backButton setTitleEdgeInsets:UIEdgeInsetsMake(0, 5, 0, 0)];

The goal is to add some separation between the image and the text.

Did you file this as a radar? It certainly appears to be a bug in the UIButton's intrinsic size calculations.
I was ready to file a radar, but this actually seems to be an expected behavior. This is documented on UIButton's *EdgeInsets properties: "The insets you specify are applied to the title rectangle after that rectangle has been sized to fit the button’s text. Thus, positive inset values may actually clip the title text. [...] The button does not use this property to determine intrinsicContentSize and sizeThatFits:."
@GuillaumeAlgis I would argue that although this is stated behavior, it is not at all what one would expect to happen when using autolayout. I've filed a bug and would encourage others to file one as well.
If you can link to the radar bug here, can we click on it and +1 on it ?
from titleEdgeInset documentation: The insets you specify are applied to the title rectangle after that rectangle has been sized to fit the button’s text. Thus, positive inset values may actually clip the title text. So by adding inset you are forcing the button to clip the text for sure

n
n.Drake

You can get this to work in Interface Builder (without writing any code), by using a combination of negative and positive Title and Content Insets.

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

Update: Xcode 7 has a bug where you cannot enter negative values in the Right Inset field, but you can use the stepper control next to it to decrease the value. (Thanks Stuart)

Doing this will add 8pt of spacing between the image and the title and will increase the intrinsic width of the button by the same amount. Like this:

https://i.stack.imgur.com/g5azb.png


It's using contentEdgeInsets (which is not buggy) to let autolayout to increase button width. And move the label to empty space in the right. Clever way to workaround the title edge inset bug.
This trick no longer works. Interface builder does no longer accept negative values in the Right field.
@JorisMans You cannot type negative values in, but it worked for me by using the stepper control to the right of the text field to step down to the required negative value... go figure!
This should be the first answer, why is it down here? I've tried the other 5 before finding this...
I made Right of content inset 16 to center the text in UIButton
j
jaredsinclair

You can solve this without having to override any methods or set an arbitrary width constraint. You can do it all in Interface Builder as follows.

Intrinsic button width is derived from the title width plus the icon width plus the left and right content edge insets.

If a button has both an image and text, they’re centered as a group, with no padding between.

If you add a left content inset, it’s calculated relative to the text, not the text + icon.

If you set a negative left image inset, the image is pulled out to the left but the overall button width is unaffected.

If you set a negative left image inset, the actual layout uses half that value. So to get a -20 point left inset, you must use a -40 point left inset value in Interface Builder.

So you provide a big enough left content inset to create space for both the desired left inset and the inner padding between the icon and the text, and then shift the icon left by doubling the amount of padding you want between the icon and the text. The result is a button with equal left and right content insets, and a text and icon pair that are centered as a group, with a specific amount of padding between them.

Some example values:

// Produces a button with the layout:
// |-20-icon-10-text-20-|
// AutoLayout intrinsic width works as you'd desire.
button.contentEdgeInsets = UIEdgeInsetsMake(10, 30, 10, 20)
button.imageEdgeInsets = UIEdgeInsetsMake(0, -20, 0, 0)

why the actual layout uses half of the negative left inset value?? I have encountered the same problem!
It's great that there is a workaround, but I hope this isn't used to justify the weird behavior of UIButton.
i
itsji10dra

Why not override the intrinsicContentSize method on UIView? For example:

- (CGSize) intrinsicContentSize
{
    CGSize s = [super intrinsicContentSize];

    return CGSizeMake(s.width + self.titleEdgeInsets.left + self.titleEdgeInsets.right,
                      s.height + self.titleEdgeInsets.top + self.titleEdgeInsets.bottom);
}

This should tell the autolayout system that it should increase the size of the button to allow for the insets and show the full text. I'm not at my own computer, so I haven't tested this.


Buttons shouldn't be overrided as far as I know. The problem is that every button type is implemented by a different subclass.
intrinsicContentSize is a method on UIView, not UIButton, so you wouldn't be messing in any UIButton methods. Apple doesnt think it's a problem: "Overriding this method allows a custom view to communicate to the layout system what size it would like to be based on its content." And the OP didn't say anything about different buttons, just the one.
This definitely works and is the solution I went with. intrinsicContentSize is indeed a method on UIView and UIButton is a subclass of UIView so of course you can override this method; nothing in Apple's docs says that you should not. Simply make a UIButton subclass using Maarten's overridden method and change your UIButton in Interface Builder to be of type YourUIButtonSubclass and it will work perfectly.
Seems to me intrinsicContentSize for UIButton should add in the titleEdgeInsets, I'm going to file a bug with Apple.
I agree, and the same for imageEdgeInsets.
r
rdelmar

You haven't specified how you're setting the insets, so I'm guessing that you're using titleEdgeInsets because I see the same effect you're getting. If I use contentEdgeInsets instead it works properly.

- (IBAction)ChangeTitle:(UIButton *)sender {
    self.button.contentEdgeInsets = UIEdgeInsetsMake(0,20,0,20);
    [self.button setTitle:@"Long Long Title" forState:UIControlStateNormal];
}

I am indeed using titleEdgeInsets. I need to distance the title from the image, not the image from the edge of the button. Maybe I should just use an image with some padding in it? Seems hacky though.
This works perfectly in combination with autolayout, thank you!
This is the better solution, as it does exactly what you want without touching intrinsicContentSize.
This does NOT answer the question when using an image and needing to adjust the inset between the image and the title!
m
monkee

And for Swift worked this:

extension UIButton {
    override open var intrinsicContentSize: CGSize {
        let intrinsicContentSize = super.intrinsicContentSize

        let adjustedWidth = intrinsicContentSize.width + titleEdgeInsets.left + titleEdgeInsets.right
        let adjustedHeight = intrinsicContentSize.height + titleEdgeInsets.top + titleEdgeInsets.bottom

        return CGSize(width: adjustedWidth, height: adjustedHeight)
    }
}

Love U Swift


Even though you aren't supposed to, it's better to subclass in this case because Apple docs explicitly state that intrinsic size does not include titleEdgeInsets in its calculation and so by using an extension you are violating not just Apple's expectations but all other developers who read the docs.
overriding inside an extension is unsupported and results in undefined runtime behavior. see: stackoverflow.com/a/38274660/4175475
s
shim

This thread is a bit old, but I just ran into this myself and was able to solve it by using a negative inset. For example, substitute your desired padding values here:

UIButton* myButton = [[UIButton alloc] init];
// setup some autolayout constraints here
myButton.titleEdgeInsets = UIEdgeInsetsMake(-desiredBottomPadding,
                                            -desiredRightPadding,
                                            -desiredTopPadding,
                                            -desiredLeftPadding);

Combined with the right autolayout constraints, you end up with an auto-resizing button which contains an image and text! Seen below with desiredLeftPadding set to 10.

https://i.stack.imgur.com/RVdm9.png

https://i.stack.imgur.com/s6lL8.png

You can see that the actual frame of the button doesn't encompass the label (since the label is shifted 10 points to the right, outside the bounds), but we've achieved 10 points of padding between the text and the picture.


This is the solution I've used as it doesn't require subclassing. Won't work if your button has a background, but that's not usually a problem with iOS 7
This will work with a background image if you also set the content offset of the button (positive value >= title inset).
o
orj

I wanted to add a 5pt space between my UIButton icon and the label. This is how I achieved it:

UIButton *infoButton = [UIButton buttonWithType:UIButtonTypeCustom];
// more button config etc
infoButton.contentEdgeInsets = UIEdgeInsetsMake(0, 0, 0, 5);
infoButton.titleEdgeInsets = UIEdgeInsetsMake(0, 5, 0, -5);

The way contentEdgeInsets, titleEdgeInsets and imageEdgeInsets relate to each other requires a little give and take from each inset. So if you add some insets to the title's left you have to add negative inset on the right and provide some more space (via a positive inset) on the content right.

By adding a right content inset to match the shift of the title insets my text doesn't go outside the bounds of the button.


T
TheoK

For Swift 3 based on pegpeg's answer:

extension UIButton {

    override open var intrinsicContentSize: CGSize {

        let intrinsicContentSize = super.intrinsicContentSize

        let adjustedWidth = intrinsicContentSize.width + titleEdgeInsets.left + titleEdgeInsets.right
        let adjustedHeight = intrinsicContentSize.height + titleEdgeInsets.top + titleEdgeInsets.bottom

        return CGSize(width: adjustedWidth, height: adjustedHeight)

    }

}

hello. i want to use custom extension button in interfacebuilder. plz help
O
Oritm

All above did not work for iOS 9+, what i did is:

Add a width constraint (for a minimum width when the button doesn't have any text. The button will auto scale if text is provided)

set the relation to Greater Than or Equal

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

Now to add a border around the button just use the method:

button.contentEdgeInsets = UIEdgeInsetsMake(0,20,0,20);

Why not? It automatically scales with the contents, you just have to set a minimum width (which can be smaller than the to be displayed text)
Because you define a minimum width. The entire idea of autolayout is have it done without setting any explicit (minimal) width.
Its not about the width, you can set the width to 1 if you prefer, but autolayout needs to know that the width can be equal or more. I updated my answer
You don't need the width constraint at all, the contentEdgeInset is the key, auto layout then uses that for intrinsic content size.
B
Ben Packard

The option is also available in interface builder. See the Inset. I set left and right to 3. Works like a charm.

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


Yeah, as this answer explains, the reason it works is because you are adjusting Edge: Content here instead of Edge: Title or Edge: Image.
B
Bob Spryn

The solution I use is to add a width constraint on the button. Then somewhere in initialization, after your text is set, update the width constraint like so:

self.buttonWidthConstraint.constant = self.shareButton.intrinsicContentSize.width + 8;

Where 8 is whatever your inset is.


What is buttonWidthConstraint?
This isn't a great solution, because if the intrinsic content size of the button changes, you'd need to manually update the constant of the constraint to the new value...and knowing when the intrinsic content size of the button changes is difficult without subclassing the button.
Ayup. I don't use this method anymore. Surprised it was worthy of a down vote but ¯_(ツ)_/¯
A call to setNeedsUpdateConstraints can be "manually" made after updating the button title or image. You can then override updateConstraints and re-calculate buttonWidthConstraint's constant from there. This is not necessarily the best approach but it works good enough for me. YMMV ;)