I have an image on my view, which I add programmatically & and not through storyboards. The image gets animated to move up the screen. At one point it crosses paths with several buttons and labels, which contain important text that gets blocked by the image passing over them. I want the image to move under the labels and buttons so that the text remains visible. Based on this answer IPhone Interface Builder: Z-Index, Z-order of a button, image, ui element, etc?, I tried to use editor => arrange => sendToBack/sendToFront, however, I don't think this is having any effect because the image doesn't appear in the tree of elements in the storyboard. As noted, it gets added programmatically at a certain time. Is there a way to do this?
I believe you can use [view insertSubview:imageView atIndex:0] which will place it behind all other subviews. Depending on what other subviews you have, you may need to increase the index as it controls what is placed over what in the view (lower index will go behind higher index)
As in answer to this question: Difference between addSubview and insertSubview in UIView class
If you're using addSubview:, your view will be placed on top. To control it's depth use either insertSubview:atIndex: (at exact place from bottom) or insertSubview:aboveSubview: or insertSubview:belowSubview: (which places new view above/below another known object in view hierarchy).
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I currently have a stack view that is horizontal, fill, fill equally. Inside, there are 3 generic views with different coloured backgrounds.
My current problem is that, when I set one of the views inside to hidden=true, the other two views immediately expands to fill the void. I don't want this. All I want is for the space to remain blank and the target view to be "invisible" both graphically and to UI input events.
Instead of setting isHidden=true you could set view.alpha = 0 to make it invisible and also view.isUserInteractionEnabled=false to disable UI input events.
*As #robmayoff pointed out below the isUserInteractionEnabled=false is not actually required.
As I can see in your screenshot, you are using the constraints. So, when the element hides, collapses and the other expand.
Use 'opaque' flag to make it invisible.
I have a background image for the view controller and two labels. The two labels are not showing up because they are behind the imageview. When I go to editor->arrange the send to front option is not available for the labels. And when I check on the layout debugger I can see the labels are behind the imageview. Is there another way to bring to the labels in front?
Assuming you are using IB, you can move things to the front/back of one another by rearranging them in the left panel. The first item in the list will lie behind every other item. So in this case your list of subviews should go:
1. Image
2. Label
3. Label
This will result in the labels lying one top of the image.
I have a UICollectionViewController setup. It shows something kind of like a gantt chart, with selectable bars, scrolling, etc. I want to have a "trash/delete" button that always floats in the bottom right of the screen, regardless of scroll. It will delete the current selection (if there's one) in the UICollectionView.
I see two basic approaches:
Use the Supplementary Views facility of my UICollectionView. What I dread about this, is that I'll have to muck with its layout in my layout (I'm using my own subclass of UICollectionViewLayout) to keep it positioned in the bottom right corner, regardless of scroll.
Just add a UIButton to the canvas and set it up there. Maybe this isn't even a real approach, because this is what I wanted to do. While my button may manipulate items found in the UICollectionView, it's not really a real member of the collection view. But I found when I tried to drag a UIButton onto my Controller in the storyboard, it wouldn't stick. It doesn't seem to want to add it. Do I have to change to use a UISingleViewController, and then have a top level view that I can add both my button and collection view into? And then repeat all of the handy delegate/property setup that I get for free from UICollectionViewController?
You:
drag a button on to the view
in storyboard/xib.
Then, in the hierarchy column on the left, ensure it is at the bottom. That means it will be in front of everything else.
So, if necessary move it so it is in front of (ie, below in hierarchy) the collection view.
Note that there is absolutely no problem, at all, with putting one control "in front of" the other (i.e., so that it "blocks" you from seeing all or part of the other one).
If you had a problem doing this, you've made a trivial mistake. For example you may have dragged the new button "into" the collection view, rather than as a "sibling of" the collection view. Hope it helps.
I have a UIView, defined in a nib, and I need to be able to show/hide a middle button in that view. When I show the button, I need to reposition the two bottom buttons below it, as well as make the view taller to make room for everything. When I hide the middle button, I need to move the two bottom buttons up and vertically resize the view to make it less tall. I do NOT need to animate any of this since it the changes will never occur while the view is visible to the user.
I'm new to iOS and I'm used to using Autolayout, but I can't use Autolayout in this case to handle this automatically, so my current approach is to hardcode the frame position and dimensions for the two bottom buttons for each of the two different situations. I'm also hardcoding the two different frame sizes for the view itself. In viewDidLoad, I determine if I need to show/hide the middle button and set the frames for the view and bottom buttons appropriately. This works, but if feels hacky. Is there a better way I should be doing this?
Thanks in advance for your wisdom!
You don't need to hardcode your frame sizes in viewDidLoad. The only thing you should take care of is determining that whether you need to show you middle button or not. Within the implementation file where you are allocating your UIButtons, check if the middle button has to be shown, if Yes allocate it, if not then don't. The frames of two buttons and the view should contain a factor which can set/size them accordingly.
You'd basically be managing the Auto-layout programmatically. And if you're not even allowed to that then whatever else you'd end up doing would pretty much be a hack.
I am trying to create an iOS UI where I have a set of subviews arranged as a grid on the UI and on clicking any of them I would like to expand this subview to a larger size. I am able to do the animation to expand this subview but I would also like this functionality such that other subviews nearby are pushed away.
On dimissing, this expanded view it should contract to the original size and bring back the other views to its original location.
I am thinking of a variety of ways to implement this but there are many use cases, and hence I would like some pointers in the right direction?
Does iOS itself provide a functionality by which expanding a sibling view contracts/moves the neighboring one? If not, what other ways are there to implement this?
Toms