Auto Layout: Displaying content relative to container - ios

I'm having some issues developing an iPhone application. I have a UITableView on a screen and have made a template for how I want to lay things out. I made sure that the constraints are satisfied and when my program compiles, I get no auto layout issues. However, when I run my program on the simulator, some of the text is not shown but I know it should be there. Here is how things look on the Storyboard:
However, this is how things look when I run the program on the iPhone simulator, it appears as so:
I am only worried about the From Date and To Date fields not being displayed because if I move them more to the left, I can eventually see them. Moreover, I made sure to make the To Date field's Trailing Space to Container Marginby 8 px so I don't really understand why these two fields aren't showing. Any help would be appreciated. Thanks!
Edit: Image of To Date constraints:
Edit 2: Image of how table view cell looks like now:

Most likely the labels are not showing because of size classes and the difference between the different screen sizes. In your story board the original view controller is a square shape. Make sure to pin the labels to the side of the cell that you want them to attach to. This will make sure they stay where you want them to. Also make sure that you pin the actual table view to the superview so you can see the labels. I have always pinned to the top, bottom, and both sides, to accommodate different screen sizes and rotation. You may need to change the constraints for the other size classes. This may make some things look they are bunched up a bit with the smaller screen size, but you can always change the font or the format of the cell to fit everything in.
If you want to change a constraint for another size class, just select that size class at the bottom of the story board. Select the label, and then in the size inspector you can make the constraints you don't want to be unable, and hook up some other constraints to make it work. Ray Wenderlich's web site has a great tutorial on size classes and adaptive layout. You can find it here.
Happy coding!!

Your "missing" labels are probably too far to the right, outside the screen boundaries. This could happen if your view controller is wider in the storyboard than when you run it. Make sure that your labels have constraints for trailing space -- that will cause them to always be within the screen bounds no matter the screen width.
Also, use the Debug View Hierarchy in Xcode to see where those labels actually end up.
UPDATE:
Try overriding awakeFromNib method in your UITableViewCell subclass:
override func awakeFromNib()
{
contentView.autoresizingMask = UIViewAutoresizing.FlexibleWidth | UIViewAutoresizing.FlexibleHeight
}

Related

Auto-layout constraints not working as expected

I've got a UITableViewCell that has a child view, and within it an image view and a label. I am wanting to use the child view as a means of giving some margin around the contents of the cell, thus giving me margins inbetween cells. This seemed to be the way a lot of people online recommended doing it.
I've set up my constraints as shown below:
I have performed a Update Frames on all views in the view controller. The story board shows it exactly as I'm expecting it to be on the phone. When I run it on the phone though, I get this...
I'm completely baffled at this point. I've spent two days of reading and trying to layout a simple UITableViewCell and clearly don't have a good understanding of how auto-layout works still.
I've even just laid everything out along the suggested boundaries (the blue lines) and then told the storyboard to generate suggested constraints. At which point the content of the cell just sent with 50% of it off the right side of the screen and un-viewable.
So two questions:
The storyboard more often than not shows me something that is not accurately represented on my actual device. Is this fairly common in iOS development? Should I not be relying at all on the storyboard auto-layout representation?
What do I have to do to these constraints in order to get the cells to layout on my device, like it is shown in my storyboard at this time? What constraints am I setting wrong?
Storyboard doesn't display the content according to any device by default. You can set it to your current device in its size properties(by default it is "Inferred"). Constraints are used to display the views equal on all devices. They automatically adjust UIelements according to display size. So if you want your app to run on devices of different sizes you have to rely on constraints.
I think you are setting too many constraints. Happens if you are new to auto layout. Try reading this guide. Its very helpful.

iOS / XCode Auto Layout Woes. Easier Way?

I'm wondering if xCode auto layout / constraints are really as frustrating as I think, or am I just not understanding them. For example, I started with this basic label in the view controller:
Fair enough. A box with text that has equal margins on the left/right and a smaller top margin. Now when I run any size device, that gets skewed/cut off from the device view. So right away for some reason Xcode thinks that despite me putting the entire label in the view controller, it things it should display halfway off the screen. Don't get it but okay, so I went ahead and added auto layout constraits to the right, left and top margins. The result is:
So it centered it, which is nice, but now it just ignores the fact that I made the width larger and it just shrinks it down anyways? For something so simple this seems to be very...unreliable. I then added the "aspect ratio" constraint and it seemed to look fine in all of the devices...finally!
I curiously also simply tried to get rid of all those, and simply add the "aspect ratio" constraint and the "horizontal center in container" constraint. On the main storyboard preview (not the simulator) it looked like this:
Not what I'm looking for, as it's not stretched downward like I want, they shrunk it again. However...when actually running it in the simulator...it looks perfect, the way I want it to in the first picture of the view controller.
Why the preview and simulator differed, I suppose (from reading other questions) it's because there were a few warnings after I added these. One was that the horizontal and vertical positions are one initially and will be different at run time. But when I ran it, it definitely held the initial ones and not the ones they said it would be at run time. It also told me that vertical position was ambiguous...well yeah I only set a center and aspect ratio...pretty obvious and not sure how I'd even solve that error. It solves it when I delete the horizontal center...but now it's not centered which is a step back from what I wanted.
Long story short, how do I deal with this. My previews and simulations aren't accurate with each other even for the simplest auto layout specifics. Apps nowadays are so complicated and on every device they scale and work beautifully, and this seems to not agree with even just one label.
Does anybody have any good articles, advice, or anything that would help me? This auto layout stuff seems to be so picky and that's really all I know so I have to deal with it. And don't even get me started on why the text doesn't scale with the label...why would I want the text on an iphone 4 to be the same on an ipad even when my label is increasing in size with the device?
A lot to go through, but it's just very frustrating and I can't see myself doing much else before I try to understand these basics. Thank you and much appreciated.
I think you have to understand constraints first...without that you always made things frustrating....For understand the constraints you can check this links
http://www.raywenderlich.com/50317/beginning-auto-layout-tutorial-in-ios-7-part-1
http://mathewsanders.com/designing-adaptive-layouts-for-iphone-6-plus/
It takes a bit of experience to get used to it, but once you get it, you get it for good and it's very easy.
Basically the rule of thumb is don't trust exactly what you see in storyboard when it comes to the size of the actual object. Say you have a UIView centered horizontally and vertically in the main view. True it will try to keep the size of that UIView but center it in any size device, but I would never just leave it at that. I would either:
Add width and height constraints
Add a width/height constraint and an aspect ratio constraint
Add a width constraint and top and bottom constraints
Add a height constraint and leading and trailing constraints
Add top, bottom, leading, and trailing constraints
In other words, the exact size of the object should always be determined via the constraints, and not by the UIView itself. This gets away from the finicky behavior and also ensures that it's displayed on any device exactly the way you intend it to.

Xcode - Adding constraints to UITableView so that it fits all screen sizes

I've read quite a few tutorials and watched numerous videos on using constraints in Xcode. For some reason, I'm still missing certain aspects that are necessary to make the user interface look the way it's supposed to for all screen sizes.
Currently, I have a UITableView laying on a view controller. The view controller is set to "Inferred" size and I have all of the different sized devices open in Assistant Editor Preview to the right so I can view the changes. I've encountered multiple problems attempting to get the constraints correct for the different screen sizes.
Problem 1: The UITableView has a width set to 600. This causes dead space to the right of the table view on the iPad preview and it causes the UITableView to extend too far on the smaller devices. If I make the width of the table view smaller so that it fits within the preview of all screen sizes and then pin the left and right edges of the table view to the edge of the Superview by specifying 0 and unchecking constrain to margins, the result I'm seeing in preview is that the entire table view disappears completely from each device size. I was surprised by this because I thought by pinning the table view to the margins, it would make the table view fit within each of the screens.
Problem 2: (This is a completely different scenario from Problem 1, above.) In this situation, I've left the size of the table view to 600 and just specified constraints for the internal components of the cell contained within the tableview. In this case, the table view is still slightly not wide enough for the iPad dimensions and it extends too far on the smaller devices which makes components in the cells to be truncated and off of center.
I've primarily been working in Storyboard with Any width, Any height set. However, if I change the setting to Compact width, Any height, I can alter the constraints to fit the smaller devices a little better, but there's still a problem with getting things to work between the 5.5 inch screen and the smaller devices.
I would like to get my UITableView to extend all the way to the edges on each device and I would like to have the view inside of the cell remain centered and keep it's relative size on each of the devices. Does anyone have any suggestions on how I can accomplish this?
if you want to make your tableview to "fill" the whole screen (device-independent) the only thing you have to do is to pin its 4 edges (top, left, bottom, right) to its superview (the viewcontrollers view in your case) with a constant of 0.
you do not specify a specific width (like in your case 600) or height.
good luck :)

How can I get my UICollectionView to be the same width as my device when using Auto Layout?

I created a UICollectionView in the storyboard editor and added it to my (custom) ViewController. Like every view controller in storyboard, it says the size is 600x600 and so the UICollectionView, which takes up the whole view, is also 600x600.
This is not correct though, as I am writing an iPhone app and so the real dimensions should be 320x568!
Because of this, when I add items to my collection, they are placed off the right side of the screen. For example, I first add a cell with an image in of size 160x213. It is left justified and it takes up exactly the left half of the screen. When I add the next image, there is a huge gap and it appears on the left side, partly cut off. The third image I would expect to appear below the first, but it doesn't appear at all. I believe it is off the right side of the screen. This implies that the size of the UICollectionView is 600x600 and not 320x568.
I should mention that I've tried everything I could think of to fix this. For example:
I tried adjusting the size of the collection view:
self.photoCollection.frame = CGRectMake(0, 0, 320, 568);
I tried unchecking "Use Size Classes" in the storyboard editor.
It seems to work if I uncheck "Use Auto Layout" but I would like to use auto layout. How do I get this work?
You can set the "Simulated Metrics" of the view in your storyboard like this below. Personally, I prefer using 3.5/4-inch to construct my layout, as with auto layout, i only need to add some constraints to elements and iOS will automatically support the 4.7 and 5 inch screen size.
I think you should google for some "Auto Layout" tutorials, and I don't think its too hard for you to pick up :D. For instance, if you want to set the collection view frame equal to your view frame. You can do it like this
Feel free to ask any follow up question if your have any, Cheers!

Popover not showing the content

I'm just trying to display a ViewController as a Popover, this is a small part of a big iPad application, and I've being trying to display the content with no success.
The worst thing is that if I create the same scenario in an empty/new project, it's works! The two View Controllers showed in the Image1 are completely new, I created those after tried to add a simple Popover action in one of my views I'm using in the App...which was not working. I tried with Clean and Build the Project more than once...just in case, but the same result. It's just not working in this specific project.
The two view controllers don't have Classes associated yet, I'm just trying to open the View2 when I click on the Button.
I appreciate your comments if I'm missing something really basic in this scenario.
(Adding more details)
I tried a different thing with the restrictions as you can see in the last two images, now I can see "something", but it's not respecting the positions.
You are using size classes of regular width & regular height (wRegular hRegular).
Design your popover view controller in Any-Any size and it should be OK.
(You can also uninstall the size classes of any object in that view controller)
There are some problems in your constraints.
The Label should have 3 constraints: left (Leading), right-to-the-text-field (Trailing) and top (Top Space):
The width and height are not needed because they are automatically set from the intrinsic content size of the label text ("Label").
IMPORTANT: When you add the constraints be sure that they are absolute, not margin related (to understand the difference read this blog post iOS8 Layout Margins).
The Text Field should have the following constraints: width and distance-from-top (Top Space):
Note that the second ("Leading Space") is the same of the "Trailing Space" of the label, not an additional one (the constraints are 5 in total).
You have to explicitly set the width of the text field (134 in my example) because otherwise the intrinsic content size will be set (and it is near to 0 because the text field is initially empty). The height is set correctly from the intrinsic size (calculated from font height, also if text is empty).
NOTE:
My answer implies some important Autolayout concepts. I advice you to study the Apple documentation to better understand them.
Hope this helps

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