I want to get my UITableViewController to scroll only when there is not enough room on the screen for all of its cells. I am using static cells that are designed to be shown in an iPhone 5, 6, and 6 plus size screen. However, when shown in the 4s screen, the bottom cells get cut off.
Ideally I would like to use AutoLayout to anchor the bottom of the tableview to the bottom of its superview as I have with other tableviews in my application, but Xcode doesn't allow me to add constraints to the UITableView in a UITableViewController. The reason I have to use the UITableViewController is because I am using a pod for a slide menu (https://github.com/SocialObjects-Software/AMSlideMenu) that subclasses UITableViewController.
I have tried to change the size of the UITableView's frame based on the screen size because I assumed a scroller would automatically be added if the cells took up more room than the containing frame. I used the following code to do so:
CGRect frame = self.tableView.frame;
[self.tableView setFrame:CGRectMake(frame.origin.x, frame.origin.y, frame.size.width, [[UIScreen mainScreen] bounds].size.height - HEADER_HEIGHT)];
However, it had no effect on the way the table was displayed.
Does anyone know how I might be able to set the bottom of the UITableView dynamically and add a scroller to the cells when the screen is too small? I would also welcome any suggestions that might help avoid having to do this at all, as I would prefer not having to do anything too hacky.
You can set the alwaysBounceVertical property to false so the tableView will only scroll when its contentSize is larger than the table view's frame which you can constrain to your view however you like.
tableView.alwaysBounceVertical = NO;
UITableViewController height is determined by automatically calculating number of UITableViewCell you have presented. You can customize the cell height so that height of UITableViewController will automatically changed as you wished.
Related
I'm trying to create layout that it structured like this:
- View
-- ScrollView
--- ContentView
---- CustomView
---- CustomView
---- TableView
---- CustomView
The tableView itself is auto-resizable using "invalidateIntrinsicContentSize" and when I add items - the height of the tableview changes, pushing the custom view below it further down.
Once enough items are added I the bottom custom view is hidden and the scroll doesn't work.
important fact - the bottom custom view doesn't have a bottom constraint. It is pushed down by the it's top constraint to the tableView.
If I do set a bottom constraint - the table view will no longer be dynamically resized.
The intended behaviour:
When a user adds items to the list and the list gets too big the ContentView will be scrollable so the user can scroll to see the bottom view.
The actual behaviour:
When a user adds items to the list and the list gets too big, the bottom view is pushed down and outside of sight and content is not scrollable.
What is happening and how can I fix it?
Below is what I think what is happening.
Since you are using UITableView, it has its own scroll view. So when the UITableView list gets too big, UITableView itself becomes scrollable rather than ScrollView's contentView becoming scrollable.
To achieve what you need, you would have to make the UITableView not scrollable and use the intrinsicHeight of the UITableView to get the actual height of UITableView along with all the items. If you have items with varying heights, it will be a problem because you won't know the height before rendering. With same height for all the rows, you can get the total height of the UITableView and set the height constraint to that value. This will increase the contentSize of the outer ScrollView, making it scrollable.
Apart from UITableView, you can also use UIStackView. This is because you are not using the reusing capabilities of UITableView anyways. Managing the datasource and delegates should not be a big problem.
You can create a constraint for tableview height, And take its reference to your swift file, by dragging it as you take other views. Now in your code, Just do this
tableViewHeightConstraint.constant = tableViewNoOfItems * tableViewCellHeight;
if you have set other constraints perfectly inside scrollview, It should work perfectly. Means TableView should have top, bottom, left, right margined constraints from the ScrollView.
try this code
tblViewHeight.constant = CGFloat( tableview row count * 45 )
var size = contentView.systemLayoutSizeFitting(UILayoutFittingCompressedSize)
if size.height < scrollView.frame.size.height
{
size = scrollView.frame.size
}
contenViewHeight.constant = size.height - scrollView.frame.size.height
scrollView.contentSize.height = contenViewHeight.constant
What I think you could do is:
Disable tableView's scroll tableView.isScrollEnabled = false
Every time a user adds items to the list, reload the tableView
Also using UIStackView with vertical axis and .fillEqually distribution as a Content View would be much more convenient as you won't need to set any positional constraints to your views, but may need to set height constraints if intrinsic content size can't be determined by the engine
My pure AutoLayout UITableViewCell looks like this in Interface Builder:
UITableViewCell
|-> UITableViewCell.contentView
|-> UIView (ScrollViewContainerView)
|-> UIScrollView
|-> left (fixed)
|-> center (fill remaining)
|-> right (fixed)
The UIScrollView contains a left, center, and right UIView. left and right are both fixed width, while center expands to fill the remainder of the UIView. The UIScrollView constraints are to align all edges to ScrollViewContainerView. ScrollViewContainerView constraints are to align all edges to the UITableViewCell.contentView. I have a constraint on center's width to be a multiple of ScrollViewContainerView's width, so the UIScrollView scrolls left and right, but the height is fixed and does not scroll. Note that the UIScrollView has been subclassed to include this code so that the UITableView can detect a tap on the cell to toggle selection.
The issue is that I currently can either scroll the UITableView containing these UITableViewCells up and down or I can scroll the UIScrollViews in the UITableViewCells left and right, not both.
When ScrollViewContainerView.userInteractionEnabled == YES, I can't scroll the UITableView up and down, but I can scroll the UIScrollView left and right. When ScrollViewContainerView.userInteractionEnabled == NO, I can scroll the UITableView up and down, but I can't scroll the UIScrollView left and right. userInteractionEnabled == YES on everything else in the above hierarchy.
I can get away with having ScrollViewContainerView as a sibling view to the UIScrollView (making the UIScrollView the direct descent of contentView -- can't get rid of this view completely, because I require it to get the dimensions for the UIScrollView frame). In that case, the opposite handling with userInteractionEnabled holds.
I know I've done this before in other projects before, but starting fresh again, I can't seem to figure out what step I'm missing. Currently using Xcode 6 6A215l targeting iOS 8, though I have reproduced the issue under Xcode 5 targeting iOS 7.
It sounds like the scrollview is causing your tableview to not allow userInteraction when being scrolled. I'm sure that if you called - (void)scrollViewDidEndScrollingAnimation:(UIScrollView *)scrollView in the UIScrollView delegate (not sure for iOS 8), but you could just do
- (void)scrollViewDidEndScrollingAnimation:(UIScrollView *)scrollView {
if(scrollView.dragging == YES) {
self.<scrollViewName>.userInteractionEnabled = NO;
}
}
This is untested code, but it's just a bit of help to get you where you need to go.
Hope it helps!
I met some similar problem.
I have a scrollView in tableViewCell. All works fine.
Until one day, someone told me that the tableView can't scroll up/down when finger is touched on the scrollView in 6p. Just in 6p, not in 5, 5s,or6.
This makes me almost crazy.
Finally, I set the scrollView's height smaller than the height in storyboard.
Biu ~ It works~~~
Still, I don't know why.
#user2277872's answer put me on the right track to look at the output of the UIScrollView delegate methods of the UIScrollView in my UITableViewCell subclass. Putting an NSLog() in scrollViewWillBeginDragging: made me notice that the UIScrollView was receiving scrolling events while I was trying to scroll the UITableView. My UIScrollView had a contentSize larger than its frame in both directions, but I've forced that view to only scroll horizontal, so ignored the height and reset it. That force was my undoing and I should have known it at the time -- the correct solution is to fix the frame height. If the UIScrollView doesn't think there is more vertical content, it will correctly forward the swipe up/down gesture to the UITableView.
While I attempt to figure out why my contentSize is too large when it wasn't before (thinking I'm missing a clipToBounds somewhere), what I'm doing to force horizontal scrolling temporarily is (in the UITableViewCell's subclass):
- (void)drawRect:(CGRect)rect
{
[super drawRect:rect];
CGSize contentSize = self.scrollView.contentSize;
contentSize.height = self.frame.size.height;
self.scrollView.contentSize = contentSize;
}
EDIT: Actually, this is seemingly better than overriding drawRect. This would be in the UIScrollView subclass:
/*
* Lock to horizontal scrolling only.
*/
- (void)setContentSize:(CGSize)contentSize
{
[super setContentSize:CGSizeMake(contentSize.width, 1)];
}
The height struct member isn't too important, as long as it's guaranteed to be smaller than the frame.size.height of the UITableViewCell. Still hacky, still need to find why I could clip before and not now.
I have two questions related to UITableViews.
1) The first one is, what is the gap at the top of the UITableView? My app always starts with the top cell not flush with the top of the tableview (as shown in the second image), it starts about one cell lower, i.e. where that gap is in the interface builder. I can't find where that is coming from, or why.
2) I can't seem to resize the uitableview programmatically, I'm trying to reduce the height after a popup appears. I've shown an example of it not working in the second picture.
Here is (an example of) what I am trying at the moment:
- (void)viewDidLoad
{
[super viewDidLoad];
self.table_view.delegate = self;
CGRect tableBounds = self.table_view.bounds;
tableBounds.size.height -= 100;
self.table_view.bounds = tableBounds;
CGRect tableFrame = self.table_view.frame;
tableBounds.size.height -= 100;
self.table_view.frame = tableFrame;
}
Thanks!
UITableView Selected:
Simulation:
In your xib (or storyboard) put your UITableView at position (0,0). ( the same position as the navigation bar).
The first image shows that your table view has problems even in Interface Builder. It looks as if you've set the top inset incorrectly; check your edge insets.
The reason your resizing code is not working is probably that it is too early (viewDidLoad); put it in viewDidAppear: and see if that works, and if it does, try moving it back to viewWillAppear: so the user doesn't see the resizing. If it doesn't work, it might be because you're using auto layout; you can't manually alter the frame of something whose frame is dictated by auto layout. (Your resizing code is also silly; you want to set the frame, not the bounds.) But it might also be because you're using a UITableViewController in a UINavigationController; if you do that, the table view is under the navigation controller's direct control and its size is not up to you.
What I have in the view controller view are :
An image of fixed height
Few labels
Table view with n rows.
Once rendered I want everything here to be inside the scroll the view so the user can scroll the entire screen as needed. Note that the scrollView needs to expand to the entire size of the tableView to show its full contents. I have tried different ways of doing this but unable to do it. I would appreciate any pointers or code segment to get this done.
There are essentially two ways to do so.
tableHeaderView
The first way involves the tableHeaderView property of the UITableView instance you have. You can simply add the UITableView with the constraints/frame/autoresizingMask that allows you to put it full-screen. Done that, you simply do (i.e. in your viewDidLoad):
UIView *headerView = [UIView new];
// Here I am supposing that you have a 200pt high view and a `self.tableView` UITableView
headerView.frame = CGRectMake(0, 0, self.tableView.frame.size.width, 200.0);
UIImageView *fixedImageView = [UIImageView new];
// configure your imageView..
[headerView addSubview:fixedImageView];
// configure labels as you want and add them to headerView as subviews
// Now set `UITableView` headerView
self.tableView.tableHeaderView = headerView;
If you want to use AutoLayout for your tableHeaderView, I suggest you to take a look at this question
Dynamic scrollView
Another way to do this is to to create an UIScrollView, put everything inside, and let it scroll. The downside of this method is that if you are using floating section headers for your UITableView, they will not float due to the fact that the tableView is going to stay fixed, while the parent scrollView is going to scroll.
On the other side, this approach is more AutoLayout friendly due to the fact you can use constraints easily.
To do so, you start adding an UIScrollView to your view, and placing all your other views inside it.
Be sure to add a Vertical Spacing constraint between the first view inside your scrollView (I suppose the UIImageView) and the scrollView top, and between the last view (I suppose the UITableView) and the scrollView bottom, to avoid an ambiguous content size.
You should have something like that (I omitted the labels for the sake of brevity):
Note that every view is inside a parent UIScrollView
After that, add an Height constraint to the tableView, and add an IBOutlet to your view controller subclass, i.e. like this:
#property (weak, nonatomic) IBOutlet NSLayoutConstraint *tableViewHeightConstraint;
Now you only need to configure this constraint to reflect the tableView natural height, given by its rows, etc. To do so, you simply calculate the height in this way:
// Resize TableView
CGFloat height = self.tableView.contentSize.height;
self.tableViewHeightConstraint.constant = height;
Now the tableView will resize, and due to its constraints it will adapt the parent scrollView contentSize.
Just be sure to refresh this height constraint anytime you reload the UITableView dataSource.
I am using a UICollectionView with fixed size CollectionViewCells. I display this CollectionView in a popOver with an UIPopoverController.
My goal is that the popOver automatically resize to the CollectionView's content. So if I only have 4 cells, than it should be small. And if I have more cells, it should be bigger. I want to avoid the empty space left in the popOver.
So I don't want a fixed popOver size, but a variable one depending on the number of cells in the CollectionView.
Any suggestions?
I had a hard time figuring this out myself but just got it finally. You have to access your Collection View's collectionViewLayout property and then use the collectionViewContentSize method to get the size of your content. You can then use those to resize your Collection View by setting it's frame.
CGRect rectangle;
rectangle = _collectionView.frame;
rectangle.size = [_collectionView.collectionViewLayout collectionViewContentSize];
_collectionView.frame = rectangle;
Now that your collection view is sized to it's content, you can set the popOver's size based on the collection view size. It may look something like this.
popOver.frame = _collectionView.frame;
or
[popOver sizeToFit];