I'm following a tutorial that had us set a UILabel to be aligned horizontally in the container (center horizontally) and set the offset by 40. The instructor then set the trailing top space distance to the nearest UILabel above it. At first, I thought the offset was another way of setting the trailing top space distance, but I must be wrong. I was wondering what it exactly does?
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I have one label to the right side of parent view.On top of label there is a view.I have given below constraints to label.
Align leading to top view (constant<16) LOW PRIORITY
Top space from parent view
Trailing space to parent view (constant=28) HIGH PRIORITY
I want when text inside the label increase it should change it's position.it should move towards left but at the same time it should also move towards right.I mean should increase it's width in both directions.As of now it's only moving towards left & keeping fix position from right.
Please tell how can i achieve this task?
i think if you set center alignment for label alignment you should get answer you want.Also give same priority to leading and trailing.
This will not work as the trailing space to super view constraint will most likely always win, as you have observed.
The width and height of the label is taken care of by its intrinsic content size and hence no constraints are needed for that. As far as position goes, the y is taken care of by the top space constraint. Finally the x will need a constraint that will allow it to grow in both directions as mentioned. To enable this behaviour remove the leading and trailing constraints and add a horizontally centered constraint. This will centre the label to its super views centre. To offset the position left or right you may choose a constant value or use the multiplier property.
The multiplier is good for positioning a certain percentage of the superview regardless of its size. e.g.: if the superview is the root view then a multiplier value of 0.5 places the label quarter of the way across the view, 1.0 makes the centre x align exactly, 1.5 makes it 3/4 across from the left.
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.
I have a UIButton and a UILabel constrained to be a standard distance from the bottom of the Superview. Works well on the iPad, but on the smaller iPhone screens, when other elements take up too much space, these views are pushed off the edge of the screen despite their constraint to remain a standard distance from the bottom. Why is this so?
What I would like to have happen is for the four rectangles to shrink in size so that there is still room for the "Go Back" and "Question" label to remain a standard distance from the bottom. The four rectangles can maintain aspect ratio and equal width/height by all shrinking at the same ratio. I have no constraints on their needing to be equal to or larger than a certain size. I've tried lowering their Content Compression Resistance Priority as well.
Configuration:
(I have also tried "equal" and "<=" in top spacing between "Go Back" & bottom left rectangle)
("Greater than or equal" works best on iPad to keep "Go Back" at the bottom of the screen)
How it looks on iPhone 6 and iPhone 6+ - with the labels cut off at bottom:
Did you try to lower those four buttons' height constraint's priority??
For example like this, try to set them to 750
You can make this work with a couple of changes and additions. Give the leading and trailing constraints between the top 2 rectangles and the superview a lower priority (I used 749), but still keep them as "equal". This will keep them at the standard distance from the edges if it's possible, but will allow them to have a larger spacing if the vertical space combined with the aspect ratio requires it. The problem with this, is that since they aren't required any more, when those constraints need to stretch, there's nothing that says they have to stretch equally; therefore, we need some way to keep the rectangles centered. So, instead of a spacing constraint between the left and right top rectangles, add a small view (I used 8x8) that has a centerY constraint to one of the rectangles, and zero constant spacing constraints to the two rectangles. Give this view a centerX constraint to the superview; this construct will give you the same spacing between your rectangles that you had before, but will keep them centered in the superview while allowing them to shrink in width (and height to keep the aspect ratio) if need to accommodate the vertical space.
I am having troubles aligning multiple images by using auto-layout in xcode.
I tried different settings, but nothing seems to work yet (refer to attached photos).
It would be great to hear some opinions from you guys, either in code or storyboard.
I want the image to be aligned equally in different screen sizes.
Too much space
Last image scaled too much
When Equally width is set
Constraints Setting
You need extra views to achieve this
In the sample picture the red rectangles they are all invisible UIView with constraints:
fixed length leading space to the view on the left(or the superview)
fixed length trailing space to the view on the right(or the superview)
fixed length height
This way it's the invisible views who have different width in different screen size while the size of images between them is fixed.
For left most item you should specify leading space to superview, for right most specify trailing space to superview. For all inner gaps between views specify horizontal spacing and for each neighbor view specify equal width constraint. Additionally I recommend for you to specify Align center Y for all views and set the y position constraint only for one of them
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.