I want to split UITableView into two parts, top part and bottom part when I tap somewhere.
the hidden part will open with animation. could anybody please tell me how to do that?
This effect just like at iOS app groups at desktop.
I think "how to split anyview into two parts" is what i want.
My fitst thought is that write code to take a shot of current screen as an image, and disabled the top and the bottom parts. then move down the bottom part.
I don't konw is there an API to do that quickly? or there already exists a repo on Github.
here is a sample image http://oi40.tinypic.com/2hhdw5y.jpg
Make the 'hidden part' a regular table view cell.
In heightForRowAtIndexPath, return the normal cell height for every cell, except for the hidden one. For this one, you will want to return either 0.0 (hidden) or some other value, when it is visible. You can store whether it's expanded or not in a bool property.
When it should expand, update the expanded property and call both
[tableView beginUpdates]; and
[tableView endUpdates];
This will show your previously hidden cell with a nice animation. You can also use this mechanism to hide it again.
You can use expandable tableview and design the tableview according to your needs.
https://github.com/OliverLetterer/UIExpandableTableView
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.
On iOS, when you append something to the beginning of UITableView's data source, the cell will "animate in" and push the rest of the cells down only if the user is already scrolled to the top. When the user is scrolled down farther down the list and a new item gets appended to the top, iOS does not automatically move the cells down.
When a new cell comes in from the top, how do I determine between the two?
My use case is that when the user has scrolled down past the iOS point, I can display a "new item above" button for the user to click . (similar to Twitter)
I'm using dynamic height for cells, so hard coding the scrollView by pixel isn't the most ideal way. I'd like to utilize iOS's way to determine it.
There is an array available of all visible cells' index paths called indexPathsForVisibleRows. You can access that property and check to see whether or not your first row is one of them, and go from there. You can also access visibleCells property to get the actual UITableViewCells themselves.
How to determine whether the user has scrolled past the first cell: a UITableView is a subclass of UIScrollView, so you can just look at the contentOffset property.
I'm not exactly sure that that's enough to accomplish what you want though. You could also maybe take advantage of the fact that tableView's cellForRowAtIndexPath: method only returns a cell if it's visible, and request the first cell. I've never tried implementing something like this before though so there might be a better approach.
I'm building a dictionary app, and one of the features is that you can "drill down" into a definition. You look up a word, there's a word in the definition you don't understand, so you tap that word and the app shows you the definition for that word, if available. This is pretty standard for iOS dictionary apps on the App Store, if anyone's familiar.
One feature is that I am going to have a bar that shows each word as you drill down, so you get a sort of "chain" of words across this horizontal bar. The idea is you can tap on the words in the chain to navigate forwards and backwards through your chain of words.
To represent this chain I am using a UICollectionView, with a subclassed UICollectionViewController. Since it's essentially a "grid" with a single row, this made sense to me. I'm using a storyboard, so I simply embedded my custom controller into the main view, pass events back and forth between the master controller and this custom collection controller. Pretty simple.
Now, let's say the user taps many different words, so you get the "chain" of UICollectionViewCells growing across the bar from left to right until you hit the edge. Since UICollectionView is based on/has a UIScrollView in it, this shouldn't be a problem. My concept is that, if the number of items to be displayed exceeds the width of the view, the CollectionView would expand the contentView and place items off the right edge of the view port, and I could then programmatically scroll the view to show the newly added item.
Here's the code that I use to do this (edited). It's a method that I call in my subclassed UICollectionViewController:
- (void)reloadDataWithAnimation
{
[self.collectionView performBatchUpdates:^{
[self.collectionView reloadSections:[NSIndexSet indexSetWithIndex:0]];
} completion:^(BOOL finished) {
[self.collectionView scrollToItemAtIndexPath:[NSIndexPath indexPathForRow:model.data.count - 1 inSection:0]
atScrollPosition:UICollectionViewScrollPositionNone animated:YES];
}
}];
}
This is more or less what I'd normally do with a UITableView: tell it to reload its data after I have changed the model. It didn't quite work at first until I found a question on SO that covered the use of performBatchUpdates, and I had trouble doing the scrollToItemAtIndexPath until I realized it needed to go into the completion block.
Now, here's the funky part: everything works fine before the items fill up the whole view. The first time an item would go beyond the boundaries, the CollectionView places the item below the last item in the row. This looks really strange because the view is only one row tall, so you can kinda half-see the item parked below the last one in the row, mostly obscured. No scrolling occurs.
At this point, if you scroll the CollectionView back and forth, the item reconfigures itself and moves into the correct position. Or, if you add another item, they align correctly and the view scrolls as intended. Successive additions work just fine. However, if you scroll back to the left and then add another item, it briefly appears underneath the last currently visible item in the viewport, then the view scrolls off to the far right and as it scrolls the misplaced item jumps up into its proper position.
Although I began posting this question as I could find nothing on Stack Overflow, in the course of writing my question, the Similar Question sidebar updated and I found similar questions, and eventually an answer.
Similar question: UICollectionView cell layout is out of the collection view's bounds
Apparently this issue is known to Apple.
Here is the solution linked to in the above question: https://stackoverflow.com/a/13389461/700471
The code that Nick Snyder posted solved the problem for me perfectly.
Edit: Additionally, in the end I subclassed UICollectionViewLayout, bypassing FlowLayout, and made my own layout with this tutorial.
I'm new to iOS and MonoTouch, and I have a pretty basic need - I have two vastly different views to display in the same table cell depending on whether it is selected or not. When you load the app I'll present a list of products in a custom UITableView, with all the rows deselected and each row basically just showing the product names in a label. As soon as a user taps one of the rows and selects it, I show a very different view with more of a shopping cart layout. Since the two views are so different they have vastly different sizes. What i need is for the cell itself (or row?) to grow and shrink according to the natural height of whichever view is currently being displayed.
I'm using descendants of UITableViewController, UITableViewSource, and UITableViewCell for the solution. What I do is add both versions to the cell's ContentView, then set the Hidden property as needed when the cell/row is selected/deselected to show the right layout. That works well. I'm in demo mode right now, so I'm not overly worried about efficiency or responsiveness, that will have to come later.
I know that GetHeightForRow is responsible for sizing the rows but it only gets called once, when the cell is first shown. It seems to me that I need to alert the TableView to re-poll the source for a new size as the views are changing, but I can't figure out how to do it.
I tried (rather hopefully) to cause GetHeightForRow to be invoked again manually using Cell.SetNeedsLayout and Cell.SetNeedsDisplay, hoping that would cause the table to re-query the source for new dimensions, but no joy.
I tinkered with the direct approach, trying to size the contentview itself but it didn't seem as if it was leading anywhere. I feel as if the table needs to be told to query for a new row size, but I'm open to any suggestions.
Surely I'm not the first to attempt this? What am I missing?
Try forcing GetHeightForRow to be called again by calling ReloadRows instead.
You may or may not have to specify begin/end updates (this might just be for animation, though?)
tableView.BeginUpdates();
tableView.EndUpdates();
I have a drag&drop operation between 2 UITableViews. The cell could be reordered in the source TableView, or move to another TableView.
Because I need to move the cell between the two, I can't use the default reorder support. However, I want to make a similar animation like when the cell is moving around and the cell below them slide out.
Any hint in how do this animation?
UPDATE:
You can see what exactly I'm looking for in the pulse app.
You can always use deleteRowsAtIndexPaths:withRowAnimation: to remove it from the source and insertRowsAtIndexPaths:withRowAnimation: to insert it into the destination.
if you want to do something similar to what makes "Pulse" you have to use "UIScrollView" for each row that you have and within the Views you need, if you do it UITableView is more complicated and would not be so easy to move between them