When using Auto Layout to position a label, I always get very imprecise results. In the example below, I have aligned the top and left edges of a UILabel to a parent UIView:
There is empty space on all four sides of the text, but the amount of empty space at the top and bottom is especially horrible. It is very tedious to take screenshots and figure out how many points I would need to offset the constraint's constant value to make the text line up properly. Is there any way to for the UILabel to properly reflect the rendered text in its frame?
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I'm trying to make constraints via Snapkit in a table view cell but my problem is I need to find out which element has max y position (The lowest one).
I have an UIImageView and next to image view UILabel elements. The label text is dynamic and could be very long or very short. Below these 2 elements, I have another one that should be aligned based on the label height, either taking image view or label.
My question is how to find which element (UIIMageView, UILabel) has a bigger Y position.
To be more clear I attached a draw with simple two cases.
Set a greaterThanOrEqualTo constraint on both elements.
In "plain language":
AnotherElement.top >= ImageView.Bottom (with constant of 12, or however much space you want)
AnotherElement.top >= Label.Bottom (with constant of 12, or however much space you want)
I would like to align the start of the text of two UILabels. I aligned the two UILabels (with the yellow and grey background) and used sizeToFit: to shrink the UILabels to the content but the text is not perfectly left aligned. There is a gap on the left. The gap is bigger or smaller depending on the first character. I would like to align the red lines in the following picture. There is even a small gap with the small font in the grey UILabel but it's barely visible.
With the Z character the gap is smaller but still visible by the yellow area left to the Z
A simple UILabel alignment does not help for my specific problem, because the text content is dynamic and not static. So there could be any combination depending on the data I get from the backend. Therefore I was hoping for a UIFont or UILabel attribute that could return the size of the gap based on the current rendering of the text.
I know that there are great UIFont related attributes like baseline, capHeight and ascender one can access to align text but there seems to be no attribute that would return the value of this gap on the left.
If this doesn’t need to be two UILabels, you could have one with attributed text. Then both lines would be subject to the same layout.
I haven't tried the GUI which people have been posting Screen Shots of, however... the behaviour is consistent with the very nature of typography.
The font sizes are completely different, therefore the width of an em is different, subsequently the letter-spacing is also different.
See this: http://www.w3.org/WAI/GL/css2em.htm for more information.
I know this answer doesn't give you what you have asked for, however it should explain why this is happening.
For customisation such as this (if HTML and CSS) I would use a negative / positive margin on the sub text, however seeing as you are using backgrounds use padding (or the equivalent in your GUI).
Use attributed text of UILabel
set indentation as per your requirement
ref screen shot
Select both the labels and add a constraint called align leading edges.
In my app for iOS 8, I have a UISegmentedControl that stretches to fit the width of the device's screen. So on an iPad it's more pixels wide than it is on an iPhone 6+, which is more pixels wide than the iPhone 6, etc.
Centered just beneath each segment of the UISegmentedControl, I have a UILabel. So there are 5 segments and 5 UILabels. Each UILabel has a fixed width (fixed by constraint). However if the display size increases they become uncentered.
How in Interface Builder can I specify a constraint that will force each UILabel to become centered beneath each segment? I would be happy if I could just get the elements to remain proportionally spaced with each other as the display size scales, but I can't figure out how to do that, either.
All I can seemingly do is to center the middle UILabel directly under the middle segment by specifying a Center X Alignment between that and the UISegmentedControl.
I specified a Horizontal Space constraint between all the UILabels, and between the outer UILabels and the edges of the view, and set all these to "greater than or equals". They all have the same priority, but strangely, they don't all scale proportionally to each other.
The resulting problem is that the amount of Horizontal Space between each of the UILabels does not scale smoothly as the width of the device's screen increases. If I align everything to be in the proper positions on the iPhone 5S width of screen, then on the iPad their alignment is all wonky, and only the middle one lines up with its segment. The rest of them are all off center.
It appears that there is no way to specify a percentage of the over-all display width as a constraint -- you can only specify things in terms of pixels. Really?!?!
Clearly I could make the width of the objects to be flexible, but because they are text labels with right-aligned text, that screws everything up.
Surely I'm missing something here... since the point of Auto Layout is to make your interface scale according to the screen size, surely there is a way to specify a constraint as a percentage of any given view or subview... surely!!! But how? I've read the documentation and I cannot, for the life of me, figure it out.
BTW I did see that in the past, people have used crude hacks like spacer views or multiple sets of constraints, but surely those are outdated answers, and I'm just overlooking something extraordinarily obvious... right?
You can do this by making the centerX constraint of your labels equal to the superview.trailing times 0.1, 0.3, 0.5, 0.7, and 0.9 with constants of 0. To make these constraints, add your 5 labels to the view. Give the left most one a vertical spacing constraint to the segmented control. Select all 5 labels and give give them a "vertical centers" alignment constraint. Now control-drag from each label to the right side of the screen, and select the "Trailing space to container margin" constraint. Edit each one of these trailing constraints to look like this (except for the multiplier that needs to be given the values I mentioned above):
You'll have to reverse the first and second item (which you do from the pull down on the first item), change the Label.trailing to Label.Center X, and uncheck the "relative to margin" box, then correct the constant and multiplier values.
This approach will only work if the segmented control stretches all the way across the screen with no padding to the edges. If you want padding to the edges, then you need to use a completely different approach. You would need to create 5 UIViews below your segmented control -- align the left edge of the left-most one to the left edge of the segmented control. Align the right edge of the right-most one to the right edge of the segmented control. Give the 5 views equal width, and 0 length horizontal spacing constraint from each to its neighbor. This will give you 5 views that mimic the segmented control in width, with each view being the same width as one of the segments (assuming all the segments are the same width -- if that's not the case, you're screwed). Then you only need to add your labels as subviews of these 5 views, and give them centerX and centerY constraints.
As seen on the screenshot above, each top cell has few labels. The frame of the label this question concerning is highlighted with green rectangle. It shows the title of some picture/sculpture or other exhibit, so there could be quite long strings.
I would like the text of this label to be just above author label (string with font of smaller size). So, normal text is aligned from top to bottom and if text is not enough to fill all the space, the gap is at the bottom part of the label.
For this label I would like to use the opposite approach: if text is not enough, all the text at the bottom. Is there any parameter of UILabel to implement above mentioned behaviour? Or I should manually count the amount of lines and adjust the size of the label?
This is fairly easy using constraints. To get the effect you desire:
Constrain your label's position above the author label
Constrain the label's width or horizontal position
Constrain the label to a reasonable height using a greater than or equal to
Either constrain the label's total height as less than or equal to, or constrain the vertical position to something greater than or equal to.
All these constraints can be added in IB very easily, or through code. These constraints will cause the label to grow vertically to accommodate more text, and then shrink back down with less text, which will achieve the effect of having the text grow up from the bottom.
I have a view with labels stacked vertically. The design specification for the view give a vertical offset from the baseline of the text in the top label to the text in the bottom label.
However when I code for this, the size of the top UILabel will always be big enough to accomodate the descender of the top label. So I can only program the offset from the descender, not from the baseline. In the attached picture, red offset is what I want to code for, but I can only code for the green offset. Is there any way that I can get the baseline offset correct either in the xib or through code? I do not want to do this by trial and error, as that would result in the programmed offset not matching the specs.
You can do it, but easier to show you in a screen shot than to explain it:
Change "30" to whatever your specified distance is.