In a view are a UIScrollview & UIView. The 2nd has 5 subviews (2 hidden).
I want to keep the layout of the 5 subviews (As of, time/date, Refresh & hiddens) AND center the UIView after rotation using IB's View Inspector. So far, none of the combinations I've used has worked. The UIView is not connected to the controller (as an instance variable). Its 5 subviews are.
How to accomplish this? (Listing what I've tried could fill a book.)
Labels, Soon to be gone and above are in the scroll view and are resizing correctly.
The closet I got to the desired result was 'dashing' all the lines. That led to a centered 320px UIView with the scroll view's contents exposed on either side in landscape.
Portrait with View Inspector settings:
Landscape with settings:
Here are steps to keep the bottom UIView's items center aligned and spacing constant.
Undo the left & right (autosizing) 'struts' for all the subviews. (Mine only had the top strut ON after modification & no springs on)
In the UIView's (containing subviews) Size Inspector, Show > Layout Rectangle and change X to -90.
Now change the Width to 480. Entering this may cause the elements to 'spread out' left & right to fill the 480. Some of the subviews may disappear.
Reposition the subviews back to the desired position. This might take selecting one in the Document Outline, cutting and pasting it back into view.
Optionally Clean the project.
Build & Run
The improved version with lower UIView (centered and same spacing) & it's settings displayed in Xcode:
It had to be possible in Interface Builder!!
Related
In an iOS 8 app, I'm trying to create a screen that has a "parallax header", i.e., an image header that grows as you pull down. I would like to do this using only constraints in Interface Builder, if possible.
Here is a nice guide by Pete Hare on how to do such a thing, and I've also had good help at looking at this example project by Bill Carson. However, contrary to these projects, this is not the header to a scrolling area that's taller than the screen, like a Table View; it's just one page. And for some reason, I can't get things to work in my app. I find Scroll Views in Interface Builder rather confusing to begin with. Could anyone walk me through the steps?
Why, certainly! First we'll set up a view controller with a scroll view.
Create an empty View Controller. Give its initial View the Xcode Specific Label Root View so we can tell things apart.
Add a Scroll View. Resize it to fill the view controller, and add constraints for Leading, Trailing, Top and Bottom to equal the superview's corresponding edges. (I do this by control-dragging from Scroll View to View in the Document Outline, hold down the Option and Shift key and then select all four edges, and then Add Constraints.)
Enable Bounce Vertically in the Scroll View's Attribute Inspector.
Add a simple View to the Scroll View and pin its edges to its superview -- the Scroll View -- in the exact same way as we did with the Scroll View to Root View (although this time we don't need to hold Option key when adding constraints). Give the new view the Xcode Specific Label Scrolling Content.
Xcode is not happy, it says Scroll View is missing constraints: "needs constraints for X position or width" and "needs constraints for Y position or height". Let it automatically add missing constraints, it will add constraints for the center of Scrolling Content to the center of Scroll View, in X and Y directions.
By setting a background color to the Scrolling Content, we can now run and confirm that the scroll view with vertical bounce is working as intended. Nice. Now, let's add the header.
Add a nice header image to the project assets, and drag an Image View to the Scrolling Content. Label it Header Image. Select your image asset as the Header Image's image. Drag the corners of the Image View so that it is aligned to the top, left and right edges of your view. Now let's go through the constraints to set on the Image View.
We want the top edge to be fixed to the top of the screen, regardless of how the user is scrolling. So we need it to be pinned to something outside of the Scroll View. You may try fixing it to the Root View's top edge, but unfortunately, that does not work for some reason. What does work is to pin it to the Top Layout Guide. You'll do this easiest by control-dragging in the Document Outline, between the Header Image and the Top Layout Guide and accpet the suggested constant.
The bottom edge of the Header Image needs to be pinned to something inside the Scroll View. Ultimately, we'd like it to be set to a fixed distance from the top of the Scrolling Content -- but Interface Builder won't let us do that. You can only set it to some distance from the bottom of the Scrolling Content, which is not very practical since you will then have to take the height of the device into account. What we instead do is to add another view directly beneath the Header Image, pin that view's top edge to some distance from the Scrolling Content's top edge, and then pin the Header Image's bottom edge to our new view's top edge. This could be a regular View that holds the rest of your user interface below the header. But for this example (and to demonstrate a later point in this guide), we'll use a label. Add a label directly beneath Header Image and give it three constraints: pin it's top edge to the Header Image's bottom edge, it's top edge also to the Scrolling Content's top edge, and it's center X to the Scrolling Content's center X. The distance between the label's top edge and Scrolling Content's top edge will be the height of the image in the non-dragged state. This unfortunately needs to be set to a constant in the storyboard file -- we'll have to update it programmatically. More on that later.
The last part is easy: pin the leading and trailing edges of the Header Image to the leading and trailing edges of the Scrolling Content.
Now, all our constraints are in place! If you run the app, you can see how it's working correctly constraintwise, but the image isn't scaling the way we expect it to. A couple of last tweaks before we're done.
In the Attribute Inspector, under View, set the Mode of the Image View to "Aspect Fill". That gives it the correct parallaxy behavior.
To set the height of the Header Image correctly, we need a little bit of code. First, make an outlet from the constraint between the label's top edge and the Scrolling Content's top edge -- the one we set to a fixed value -- to your View Controller's source file. Call it imageHeightConstraint. Also add an outlet from the Image View called headerImageView. A good place to update the constraint programmatically is in the viewWillLayoutSubviews View Controller delegate method. Here is some code in Objective C:
- (void)viewWillLayoutSubviews {
[super viewWillLayoutSubviews];
CGSize imageSize = self.headerImageView.image.size;
CGFloat heightForWidth = imageSize.height / imageSize.width;
CGRect screenBounds = [UIScreen mainScreen].bounds;
CGFloat screenWidth = CGRectGetWidth(screenBounds);
self.imageHeightConstraint.constant = screenWidth * heightForWidth;
}
Finally, you may notice that when scrolling up, the label -- or whatever content is underneath the header view -- is getting covered by it. This is solved by checking Clip Supbviews on the Image View's Attribute Inspector.
Whew!
(Note: I began writing this as a question and then kept writing while I solved it for myself. I guess it would do well with a little text pruning and some images, but maybe it will help someone...)
I went through ray wenderlich's tutorial about autolayouts (link) and then began working on a demo project thinking I've figured it all out but I was wrong. As shown in the screenshot below I have a navigation bar, 2 views and 1 button. The layout on portrait mode looks fine without adding any constraints on views or the button, and understandably in landscape mode views are messed up. I tried adding following constraints on views and those don't seems to work.
View#2: Select view 2 > Editor > Align > Horizontal center in container (hides view completely)
Add Top space to superview. Again view goes away from both landscape and portrait preview.
If I can display view#2 correctly I am planning to add vertical space between view#2 & view#3 and then between view#3 and button#4.
My main concern is to resize the views so that it shows all views and buttons in iPhone 4s landscape mode. Any advise or suggestions are appreciated.
EDIT: Here's the end result that I am trying to get:
The reason your views go away when you add constraints is because a UIView has no intrinsic content size, so its size is {0,0}. The view appeared when you didn't add constraints because the system adds constraints for you, if you don't add them yourself; the system added ones are top, left, width, and height. So, you need to set the size of the views somehow. You can give them explicit size constraints, you can pin them to the edges of the superview, you can give them relative heights based on other views, etc.
Since you want the 2 views to get proportionally smaller in landscape, you should give them heights that are relative to the superview. You do this by selecting the view and the superview, and choosing "Equal Heights" from the pin menu. Edit that constraint to change the multiplier to something like 0.25 for the blue view and 0.2 for the orange one (this assumes that orange or blue view are the first item in the constraint -- if they are the second, then you should use the inverse values of 4 and 5). You should also do the same for the widths, since it seems you want them to get proportionally smaller too.
Hey, I'd like to obtain what you see in the pictures: in Compact Height mode (landscape iphone) both the red and the blue view have to take all screen vertically and half the screen horizontally. In Compact Width mode (portrait iphone)they have to take all the screen horizontally and half the screen vertically. Space between views should be same size in both modes.
I used to think I have to use size classes and auto-layout constraints, but everything I tried failed miserably.
Maybe I have to use a UICollectionView and change flow direction based on orientation (if that is even possible)?
A collection view is probably overkill, because you don't want scrolling and that's the whole point of a collection view--by the time you do the sizing to stop it you'll have done all the work necessary to set a non-scrolling layout.
This is possible with Size Classes in IB. First, In general you will probably find it helpful to name the views in the Document Outline on the left in IB. You will also want to use this outline rather than try to grab the tiny constraint H-lines.
Set up all the constraints except 1) constraints linking the
OrangeView and BlueView to each other, 2) the constraints linking
the OrangeView to the top and left(leading), and 3) The constraints
linking the BlueView to the bottom and right (trailing).
Change the size class setting at the bottom to w-Compact and
h-Any in the funky box system. Now we're designing for a compact width, so views on top of each other.
Create a constraints for vertical space for BlueView.bottom to
OrangeView.Top. Also create constraint for OrangeView to
superview.leading (or ledaing,margin) and BlueView to
superview.trailing.margin. If you select any one of these constraints and look at the Size Inspector on the right (the ruler) you should see an "installed" checkbox not selected, and below that a w-Compact h-Any and another installed box, this one selected.
Now, while keeping the constraint selected just to see what happens, change the sizeClass selector at the bottom to w-Regular h-Any. Notice that in the Document Outline to the left, it should get grayed out.
Now we are designing for regular, so side-to-side. Add constraints linking the views for horizontal space, BlueView.trailing to OrangeView.leading. Also link OrangeView.top to the superview.top or top aligned to BlueView.top, and same for bottoms. You can manually edit the frame first; if not, IB will automatically fill in the wrong values, so edit these after you create them, and verify they are w-Regular and h-Any. With the ViewController selected, select "update frames" and the views should snap to their expected shape for the size class.
Let us know if this works for you or if it was unclear. Good luck!
I would like to be enlightened on the idea: shrinking of superview which would result to automatic shrinking of its subviews also. I want to know how to do this in the Interface Builder.
I still like to deactivate Autolayout for that. (select the View in the IB, in the utilities tab you go to the file inspector and uncheck the "Use Auto Layout") property.
Then:
1. In the interface builder you select the subview.
2. You go to the size inspector (2nd from right, looks like a ruler)
In the middle on the left you have a gray square with 2 arrows in the middle and 4 lines on the outside (The Autosizing box). By clicking them you can activate them (red) or deactivate them. The 4 lines on the outside represent the "stick to the superview". E.g. if you activate the red line on the right the subview will always keep its set distance to its superview. the arrows in the middle activate/deactivate horizontal/vertical autoresize.
So to make a subview stick to its superview in every direction and make it resize alongside you have to activate both arrows and all lines.
In Interface Builder I have my main UIView however inside of this I have another UIView which acts as a header (different colour background and contains centered text whereas the main UIView behind and seen below the header contains other centered text).
The app was originally built for portrait mode. Now that I have allowed landscape mode, when I rotate the device, all the text auto resizes to remain in the center of the screen, but the header view remains the same width and locked to the left of the screen so I have a lot of trailing space to the right of it as it doesnt go all the way to the other side of the screen.
After looking for a solution I still haven't found one which fixes the problem so how do I set this UIView to stretch automatically on orientation change like all the text labels?
This is simple using auto layout. Give that view a constraint to the left, right, and top of its superview, and no fixed width. You can give it a fixed height if that's what you want, or give it a height that's proportional to the height of the screen (this would have to be done in code) if you want it to be shorter in landscape.