I have a table with different cells and I need to add a scroller view with special UI in some cells:
I need to develop the UI which you can see in section 0.
So my questions are:
How can I add a scroller view?
How can I load data only for those items which are shown right now?
How can I change the width of "Line" column after scrolling to the right?
I'll answer as best I can with some starting pointers for you...
You need to subclass UITableViewCell and in your subclasses drawRect method you should add a UIScrollView to the contentView.
Not totally sure what you mean here, please expand.
In your new table cell, set it as the delegate of the scroll view you implemented, then you''ll get callbacks when the scrollview scroll with the contentOffset value, which you can use to calculate how much to grow or shrink the line items.
Related
I want to add a subview to a UICollectionView in order to make a left panel that scrolls with the collectionview.
Using
[self.collectionView addSubview:myView]
all touches become disabled and I can no longer scroll the view. I've read that adding a subview to a collectionView like this is bad practice.. is this true? Why does it disable touches from reaching the collectionView event when
userInteractionEnabled = NO
I'm trying to do this: imgur link by grabbing the frame position of the first cell in each section, and adding a dot with to myView with the same y value.
Thanks for any help!
Adding subviews using the addSubview: method to a UICollectionView is very bad practice. It can cause a lot of different problems in the normal behaviour of the CollectionView. It can obstruct the views underneath it, capture the touch events, preventing them from reaching the actual scrollView inside the CollectionView, etc. The subviews added using this method will also not scroll as the other elements in the CollectionView do.
The correct way to do what you want is to implement a new type of UICollectionViewCell for the dots, and compute their locations in the prepareForLayout and layoutAttributesForElementsInRect: methods. Basically you'll have either one or two cells in each row. Which ones will have two rows will be determined by you in the methods I've mentioned.
In fact, Apple's docs have a perfect example that's even more complex than what you're trying you achieve. You should check it out from this link.
May I know the purpose of that scroll view ? Because, if you're looking for a subview that displays only a label or image etc., You can use custom collectionview cell instead if I am not wrong... Hope it helps :) :)
I have a UITableView and one of my table cells is a UICollectionViewController subclass that contains a UICollectionView of displayed email addresses. When a user adds an email the UICollectionView and it’s cell in the table view should get taller.
I’m currently attempting to do this setting my collectionView height constraint to collectionView.contentSize.height in the LayoutSubviews method of my collection controller/cell class. My issue is that the cell in the UITableView is not changing size when this happens.
I am assuming that this is because there is nothing telling the table view that the height of the email entry cell has changed. I am currently using dynamic cell sizing - or trying to anyway. Even, if I call tableView.reloadData() this still does not work. I’m wondering if someone could give me a high-level idea of how they would set this up.
UPDATE:
I had a broken constraint issue that was part of my problem, but this is still not solved. While have proven that I can update the height constraint and that will update the size of the collection view, it's out of sync. It's always one update behind. Here's an image showing the 'UICollectionView' in green and you can see in the logs that I'm updating the constraint (yes, multiple times) each time after adding a new item to the collection, but it is not updating the bounds of the view instance. In this example, if I were to add a new item to the collection, the next time I inspect bounds.height it would be at 149.5. What am I missing!?
i had answered this question in another tableview inside tableview cell that will work for collection view too ,i explained it in this thread
ask me if you faced any problem
It seems you want to set the height of your table view cell dynamically. This detailed tutorial walks you through making a custom cell class that will have dynamic height. Unfortunately, this tutorial only walks you through how to do this with auto layout constraints and a storyboard. In the tutorial you'll notice that the height of the cell depends on the constraints put on a title label within the cell. Try doing the same thing, but applying the constraints on the content in your cell (the collection view cell).
http://www.raywenderlich.com/73602/dynamic-table-view-cell-height-auto-layout
I want to implement a UICollectionView with multiple sections which each section scrolls horizontally and independently like the attached image
I suggest you to use UITableView with customized UITableViewCells with UIScrollView as subview on its contentViews.
There are many samples, for example here
You can use multiple UICollectionViews in table cells. The tableView will scrolls vertically and The collection views can be configured to scroll horizontally by setting particular set of properties which will restrict them to scroll vertically, and they will only scroll horizontally. One constraint to consider is it is much more difficult to do animations that need to move from one table cell to another and you can't use a neat single change of collection view layout to animate all the items in your table view. But if these constraints aren't a problem then this is a relatively easy solution. I also tried it once. It worked for me. Hope that it works for you as well.
I have tried looking for an answer to this question but so far I haven't got any luck.
Context
I have a UITableView inside a standard UIViewController (NOT a UITableViewController..). I have subclassed UITableViewCell and all the cells in the tableview are from the same class.
Requirement
I would like to find an efficient way to resize the cells based on the scrolling of the tableview. For example, when the cell is at the bottom of the visible list, the height is X. When the cell moves up on the screen, its height should proportionally increase to 2X.
Additional Info
I am close to just ditch the UITableView way and start making my own control that would implement such a feat by subclassing a UIScrollView. However, I would like to see if it is possible before going this path. I did see some very interesting SO posts but nothing that would put me on the right path.
Any hint or help would be highly appreciated.
You would need to respond to the scroll view delegate method scrollViewDidScroll: and implement it to record the cell at the top of the table view and reload the table view. Then your table view delegate method tableView:heightForRowAtIndexPath: sets the cell height by the relationship between the index path and the top cell index path.
Your main issue is performance while reloading the table view all the time.
If you wanted to roll your own solution it would be along the lines of the above description anyway, but you would be able to be more efficient than the table view as the table view will call the tableView:heightForRowAtIndexPath: method once for every row for every reload in order to calculate the total height of the table content.
What i am trying to figure out is to add an UIImageView in front of the grouped UITableView while it is in editing mode, just like the ways plus/minus button behaves. There is hell a lot of footprint to build a room there if we could make use of it.
Is there any solution or workaround?
Thanks in advance!
You should be able to just add a UIImageView as a subview to the table cell and give it a negative left offset to put it outside the cell frame.
The cell may clip to its bounds by default (I don't recall offhand), but if it does, just set the table cell's clipToBounds property to NO.
You must override the UIView method layoutSubviews of your table view and check for the editing state. Then you can redraw the cell to your heart's content.