I have seen some Apps on my Watch with the "scroll up to refresh" feature, like the email app. If you scroll up when you are on the top, the content gets refreshed and a little wheel is shown on the top.
How is that done? I can't find anything in the documentation
I´ve only seen this on Apple-apps. So i guess they have a wider API. Anyway you can do a workaround. When you initialise your table you could use the
- scrollToRowAtIndex:
And specify row 1. This will now be your first row for your data. The row at index 0 will be a row with a button that will refresh the table. When you tap row 0 you could insert an WKInterfaceImage with an animation (or perhaps look for a way to do the spinning wheel yourself).
This is not the optimal way, but if you play around a little bit with it you can make it work and make it look good. Hope this helps you.
Related
I have a UITableView which has a variable amount of sections and every section has a variable amount of rows. Every section contains a section header, a section footer and the rows for that section. They are shown and displayed inside a container. Everything up until now works as expected. To demonstrate what my UITableView currently looks like:
I am now trying to implement the possibility to swipe left on the entire section, so that the header of the section, the rows inside this section and the footer of this section move to the left and display another UIView. I am capable of swiping the cells separately, but enabling this feature on the entire sections have caused headaches for the past two days. This is what I would like to achieve:
I have thought about implementing UIGestureRecognizers but I am afraid they might conflict with my UITableView. Also, I started implementing it, but I would not know how to move solely the section on which was swiped to the left.
Then I thought I could maybe implement a UIScrollView as container for each section. How I would accomplish this is still a mystery to me, but it seems like a possible solution if this could be done.
Furthermore I am out of ideas and stuck on how this should be done. It's something I have not found on the Internet so far - at least no working examples of some kind so I have zero inspiration on how to achieve the effect.
I therefor would like to ask if somebody has an idea of how this could work and what I have to keep in mind when implementing this. Every clue pointing me towards a working solution is gratefully appreciated!
EDIT: I have already seen the possible duplicate this afternoon. However, the suggestion there shows touchesBegan() on the header, which does not work in my case as I need the entire section to be "draggable".
I think one way you can implement this is with a vertical stackview containing views that contains a tableview and the trash icon. When a user swipes left on the tableview header, it will show the hidden trash icon in the view. I would think that each tableview only has one section so it will be easier to keep track of which "section" the user has swiped.
I have currently managed to arrange a similar solution. I take the rectangle of the section with rect(forSection:int), add a UIPanGestureRecognizer in which I add a UIView on top of the UITableView if touches began, I calculate the location of the finger and let the cudtom UIView follow. When a certain point (100 from left edge of the UITableView) is reached, the section gets removed with deleteSections(indexSet:with:).
This works. It does the job, but it adds an overlay to the section rather than pushing it to the left.
Therefor I am asking of someone knows if there is any way of setting the offset for one specific section or for an area of a UIView, so I can offset the rectangle of the section. I have been able to setContentOffset on the entire UITableView but this is not the desired result.
If there is no way to do this, I would consider keeping the solution I have now or maybe implement a snapshot feature which takes a screenshot and crops the rect of the frame, adding this UIImage to the custom view to simulate the section. But that would be tricky. Any ideas for this idea are also welcome.
I have to build a tableView with a top bar "slider" like the one in the youtube app in the picture below.
I just wanted to ask if it's better to:
Use just one tableView and switch the content by changing some switches in the delegates methods and reloading all the rows
or
Use two tableViews and hide the one that's not displayed
If none of the two methods above is the best one please point me in the right direction, thank you.
Option 1 :
Take a UISegmentView on the top and have a single UITableView. Change the content of UITableView on valueChange event of segment.
Option 2 :
Have look at this awesome library by Yalantis - Segmentio. I have myself used this on couple of occasions. Handy when you have to horizontally scroll the segments (exactly what you need in your case). You can have a single UITableView for this as well.
Option 3 :
Check out another useful library by Yalantis - Persei. Just hard scroll the table to see these options. Again, single UITableView.
In all, the best solution, in my opinion is to have a single UITableView. Working with multiple tableView might seem a clean way for a start, but trust me, maintainability is the key and having a single UITableView would be a better approach.
I am new to iOS development and unable to identify how Google/YouTube built this view in the YouTubeTV app. Is this built using an UITableView?
Essentially, the top row is selectable (Pre-animation). As you scroll up, the top row gets pushed up and out of view (Mid-animation), while the second row fades and grows into, and replaces, the top row). I've included screenshots of the animation in-progress. Thanks for the info and assistance.
This would be done with a UITableView or a UICollectionView. What you would do is enable paging on the Table/Collection view, so that it only ever displays entire cells in the visible area of the view. You can then manipulate the height use the heightForCellAtIndexPath: function - as an example of how it could be done on a tableview.
There is actually a really good example on github - typically we try to give more full answers on SO, but in this case, this could be relevant to you just starting out. Not affiliated in anyway, but it's a really good example.
https://github.com/aslanyanhaik/youtube-iOS
I am developing an iOS application that mainly use a UITableView.
It retrieves pages of articles from a server. We have got >25000 articles; so I have implemented a pull-to-refresh and infinite scrolling to travel across the title collection.
The ones downloaded persist using core data; NSFetchedResultsController is used to automatically update the UITableView.
However, I have implemented the infinite scrolling to be in both direction; up and down. Since the user will be allow to scroll down the 25000 article titles, I have to remove the one that the user has already scrolled. If the user scrolls up, I have to re-insert title above the current one.
Doing so, I have got a moving window inside the article collection.
I display my articles by date group using the section and header.
The problem is that because the infinite scrolling goes in both direction, I often delete or add article at a higher position in the table.
Infact to achieve that, I have got to change the predicate associated to NSFetchedResultsController.
This result by scroll being messed up. I have made it jump back to the position where it was supposed to be ish. It is not nice because it is a jump (animation:NO), if I put the animation ON, it goes all around the place before going back to the right position. And the position is not exactly the one it should be.
I am not sure I well explained my problem. I think the problem might be in the way I am using the UITableView but I am not sure how I should use it to make this better.
Cheers
If you only store article titles in Core Data, I think it can handle 25.000 titles.
However I think that the problem you've got is with the pagination of the visible elements of the table
Here is a link that I used to handle something that you requested. You'll have to tweak a little bit to use Core Data and a remote source.
Please post some code if you can so we can have a look.
In my iPad application, i've a scroll view that lists images of 20 video albums. The list of 20 images will be sent by server.
Now when the user reaches end of scroll view, i've to send a request to get next 10 videos details.
After fetching the data, i want to add them to the scroll view at the end. But I want to delete the 10 videos at the beginning. So that at a time scroll view will show only 20 video details all the time.
When user scrolls again to the end, i'll send request to server, get next 10 video details and add them to the scroll view, remove 10 beginning video details from scroll view...... and similarly when user scrolls to the beginning i'll fetch 10 previous videos and repeat the same.
Here i want to make sure the scrolling must be smooth and don't want to have flickers in scroll view. can some one suggest to have better scroll view coding to achieve my requirements please?
If your code contains scroll.pagingEnabled = YES; Then please remove this part of code.
It will surely work.
The real problem here will be in setting up cell recycling. It's not that hard to do, I have a couple examples of which you can look at, one being here. You'll need to make some changes to that code of course, it is set up in "pages" — Only one view on screen at any one time, and I don't think that's what you want.
Aside from that...
Your critical part here will be in designing your data source in a way that allows removing of old items, and adding new items, without skipping items.
For instance, the way I might approach this is to render the "last" item in your scroll view, the same as you want the first item in the scrollview to be. When the user gets to the last item, set your content offset to the start of the scrollview without animation (haven't actually tried this, so there may be a jolt that you don't want, test it and see). This will give the appearance of endless scrolling. Your data source would simply overwrite old indexes when adding new items, instead of adding to the end of an array for instance.
If you are presenting then in the form of a grid view, I suggest you take a look at AQGridView. That grid view supports cell queueing and dequeueing, which does exactly what you describe.
You can also use the delegate method scrollViewDidScroll: to determine if you're at the bottom of the scrollview and trigger the download of the next set of albums.