Can i set the UIView image to cover like in css? - xcode

At the moment the UIView is set to scale to fit. Is there any way of setting it to fill the whole element and set it to centre?

There is a content scale mode called aspect fill maybe does what you want.

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How do I get the auto-layout to work correctly in xcode?

I am attempting to get the auto-layout to work correctly. For some reason, when I change the size of the device, all of the images and buttons are out of place and don't resize at all. This is true for the 3.5 inch screen, as well as the ipad retina. When I run the simulator, the app shows exactly how it shows in storyboard. Auto-layout should be resizing everything so that this does not happen. please help!
The issue is that constraints don't scale. When you set a constraint height to 200 it will always be 200, even if the screen is only 100 high. So what you need to do is try to set constraints that makes the size dynamically rather then set the constraint height/widths yourself.
For instance, on your first label under the UIImageView set the constraints leading and trailing to 20, then set the label constraint to center horizontally on the UIImageView. No other constraints for the label. This will cause the label to shrink in width since its set to be 20 away from each side. The height will not change since there is nothing "pushing" it to shrink since you are missing a few constraints, but basically you need to use the top, bottom, leading, and trailing, constraints to the UIViewController view in order to "scale" the elements.
If you'd like I could try and set the constraints for you if you upload the project and you can then watch how I did.
Edit
It's hard for me to know what kind of behaviour you'd want, but something has to scale or change size in your set up. The easiest would be to resize the UIImageView. It's basically impossible to make it look exactly alike in every screen size, though, so you'll have to play around a bit with constraints until you understand how they work and how to adjust them according to what you want. One way is to create the layout you want and then connect them to code and scale them depending on size of the screen (this is a bit of a pain, I did that in a project recently and it took a bit of time and effort).
The easiest approach is to make the UIImageView to change its size when it needs to, and add extra space in the bottom. Here is a demo project I threw together earlier. Download here
Profile pic
1) first you set the profile pic image center horizontal to the content view
2) set height and width for the profile pic
3)set top space constraints to content view
Change Profile pic label
1)set central horizontal to profile pic
2)set width and height
3)set vertical space between profile pic
Challenges Accepted label
1) set vertical space to profile pic label
2) set Leading space to container
3) set height
and do same for the below two content . i didnt tested. check it and try
After a long night of struggling, I figured out what I needed to do. I was setting the individual view controllers to have a simulated size of 4.7inch. This made it hard for the constraints to scale across all devices since I was setting the constraints for a specific screen size. However, this would be the way to go if using size classes.
I solved my issue by using the standard 600 X 600 canvas that is available before choosing a specific size. This way, I was able to set constraints that scaled down for the smaller screens, and scaled up for the larger/HD screens. This works perfectly with auto-layout. Hope that helps someone!

Trouble with Auto-Layout

Xcode 5
I'm trying to learn the auto-layout system. Thought I would start with something simple, but I'm already getting stumped :-)
Scene: Main View -> ImageView -> View
I want to support rotation such that the Image rotates and centers on the screen, using Aspect-Fit content.
I want the smaller view to maintain it's relative position to the top edge of the UIimage view. It does't seem to understand the aspect-fit, and it aligns the sub view along the top of the main view, not the fitted image.
I think it has something to do with the fact that the small view is a sibling of the Image, and not a sub-view. I can only seem to create constraints to the superview.
.
You haven't started with something simple!
An aspect fitted image view doesn't actually change its size under auto layout depending on the image, it fits the image into the bounds that the constraints have determined, leaving the rest of its frame blank. If you set a border or background colour on the image view you will see this.
To achieve the effect you're after you would need to do the aspect fitting calculation yourself and modify the sizing constraints on the image view appropriately.

How to resize between 3.5" and 4" screens (dynamic constraints in autolayout?)

I have one view filling the screen with a background image. Other views (text fields) are in exact positions (the background image includes the text field background images). When I change from 3.5" screen to 4", the text fields don't change in the same way that the background resizes. The bg image simply resizes to fill the screen, but the text fields jump out of alignment.
Is there a way to have two sets of constraints, one for each screen size? or is there a way to have views resize proportionally to another view?
EDIT:
Is there a way to have two sets of constraints, one for each screen
size?
Yes, by adding constraints programatically and checking [[UIScreen mainScreen] bounds] to get the screen size.
or is there a way to have views resize proportionally to another view?
Yes, you could set this up in interface builder. But it will be hard to manage, I would manage the constraints manually in code since you are using a custom background image the textviews need to position exactly
You're going to struggle to get these things to line up properly with the text view backgrounds being part of the background image.
You should amend your image assets and use the background property of UITextField to have an actual background image, and remove the boxes from your main background image. The icons could be separate images as well.
Failing that, it would make more sense to have the image stretch underneath the text boxes rather than on top.
Your layout is doing what it should do based on your description, but the image isn't stretching in the right way. In your screenshots, username is always the same distance from the top, and the others are the same distance from the bottom, but that isn't how image stretching works. I don't know how you've set it up but it would make sense to have a single image the size of the 4 inch screen, which has the bottom cut off for 3.5 inch devices, and constrain everything from the top.

cocoa mac osx grid display of images of different sizes

what i'm trying to do is displaying a set of images in a grid like fashion but with different sizes as for images in landscape or portrait position, this excludes using the NSCollectionView because the item prototype's size can only be set once...
i'd go and add subviews programmatically to a scrollView but this yet again when the window's size changes and the scrollView get a bigger width, there will be just blank spaces on the right side...
you can checkout the image below for a better understanding...
http://i.stack.imgur.com/NVJjP.png
thanks in advance you guys...
what i ended up doing was implementing a purely mathematic algorithm where i calculated the (x,y) position for every new added photo depending on the previously added photos and it did a pretty good job... the container holding the photos was embedded in a scrollView, needless to say that i had to calculate the height of this container as well.

Maintain aspect ratio of a view on a NSWindow, rather than the aspect.

I have an image view that i would like to maintain the aspect ratio of but still be able to resize the window.
Set the image view scaling property to "proportionally up or down" in interface builder and set the content aspect ratio of the window containing it:
[window setContentAspectRatio:myImageView.image.size];
As far as I know, there's no way to do this "automatically", you'll need to follow the frame change of the window (with the delegate method windowWillResize:toSize:) and adjust your image view's frame however you want it to change.

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