Scrolling a UITableView cell up and then expand it - ios

I have a UITableView with custom cells in it. The cells expands when I tap on them. I am facing an issue when I tap on the cell which is half cut by the bottom screen edge of the device. When I tap on this cell, I want cell to move up and then expand to show the details but right now it just expands and I do not know if is expanded or not. I need to manually scroll the table view up to see it.
Below is my cell tapping code. I implemented the related cell expansion methods and cell is expanding properly.
- (void)cartTableView:(UITableView *)iTableView didSelectRowAtIndexPath:(NSIndexPath *)iIndexPath {
[self.temporaryCartTable scrollToRowAtIndexPath:iIndexPath atScrollPosition:UITableViewScrollPositionMiddle animated:YES];
[self expandOrCollapseCartCellAtIndex:iIndexPath];
}
- (void)expandOrCollapseCartCellAtIndex:(NSIndexPath *)iIndexPath {
self.selectedIndexPath = iIndexPath;
[self.temporaryCartTable beginUpdates];
[self.temporaryCartTable reloadRowsAtIndexPaths:#[iIndexPath] withRowAnimation:UITableViewRowAnimationAutomatic];
[self.temporaryCartTable endUpdates];
}

After expanding, call scrollToRowAtIndexPath, which should position your cell correctly.

You need to check if rect of the cell you're extending (rectForRowAtIndexPath:) is fully within the bounds of the table view (based on contentSize and contentOffset, using CGRectContainsRect and if it's not - and only partially visible - then you need to scroll it to the bottom/top of the table view.

Related

Visible UITableViewCells not resizing on rotate

I have a UITableView with custom cells. When I rotate the device, the visible cells do not resize. Scrolling to new cells works fine and when I scroll back, all is well, but is there a way to get the initial, visible cells to smoothly resize on rotate?
[self.tableview reloadData] from the UITableViewController; works, but I don't think that is the optimal solution, as it requires a network call for data retrieval.
I am already calling the following code from the UITableViewController in order to layout some gradient layers I use, but this does nothing to resize the ImageView.
-(void)didRotateFromInterfaceOrientation:(UIInterfaceOrientation)fromInterfaceOrientation
{
for (ProjectCell *cell in [[self.tableView.subviews firstObject] subviews]) {
cell.laidOut = NO;
[cell layoutSubviews];
}
}
Thanks
I believe this will do what you want:
[self.tableView beginUpdates];
[self.tableView reloadRowsAtIndexPaths:[self.tableView indexPathsForVisibleRows] withRowAnimation:UITableViewRowAnimationAutomatic];
[self.tableView endUpdates];
As long as the cells you want to reload are the visible cells.

How to show last add cell on UITableview whileloading view or reloading tableview?

all I am doing one chat application, i which i am using UITable view to display reply and response from user.in this case after some interval of time i am reloading my tableview to fetch new data from server. But the problem is that after adding new content to table view it will go at the bottom of table view and i have to scroll table view to see that one.or in other case whenever i am reloading my table it will show its first cell on view. Now my question is "is it possible to load last cell of UITableview after view gets load or reload table view?"
on search I find this line but it give me error
[sTableView reloadRowsAtIndexPaths:[NSArray arrayWithObject:[NSIndexPath indexPathForRow:sender.tag inSection:0]] withRowAnimation:UITableViewRowAnimationNone];
what is sender.tag in this line? // use of undeclared identifier sender
This line working well but scrolling the page which i dont want
[table_readText scrollToRowAtIndexPath:indexPath atScrollPosition:UITableViewScrollPositionTop animated:YES ];
Any idea or suggestion would be highly welcome.
Thanks in advance..
You can also look at the scroll view's setContentOffset:animated: method.
Going to the top would mean,
[self.tableView setContentOffset:CGPointZero animated:YES];
and the bottom would be,
CGFloat height = self.tableView.contentSize.height - self.tableView.bounds.size.height;
[self.tableView setContentOffset:CGPointMake(0, height) animated:YES];
SECOND option:
scrollToRowAtIndexPath:atScrollPosition:animated:
Scrolls the receiver until a row identified by index path is at a particular location on the screen.
- (void)scrollToRowAtIndexPath:(NSIndexPath *)indexPath atScrollPosition:(UITableViewScrollPosition)scrollPosition animated:(BOOL)animated

How to bring a certain cell to front

In my table view, I have three sections, of which the first section contains a image cell, the second section contains segment control cell, and the third section contains some label cells.
What I am doing is when the user scrolls up the table view, everything will scroll up but the position of the segment control cell will be fixed at the upper margin of the screen.
- (void)scrollViewDidScroll:(UIScrollView *)scrollView
{
NSIndexPath *indexPathOfCurrentHeaderCell = [NSIndexPath indexPathForRow:0 inSection:0] ;
UITableViewCell *headerCell = [self.tableView cellForRowAtIndexPath:indexPathOfCurrentHeaderCell];
if (headerCell.frame.origin.y < self.tableView.contentOffset.y)
{
self.cellHead.hidden = NO;
self.cellHead.frame = CGRectMake(0, self.tableView.contentOffset.y, self.cellHead.frame.size.width, self.cellHead.frame.size.height);
}
[self.tableView bringSubviewToFront:self.cellHead];
}
But the function bringSubviewToFront: does not seem to work here (the second section will be covered by the third section). I think it is because the cells are not the subviews of the table view.
What can I do if I want to pull the segment control cell to the front?
You should add the segment control as a header instead of a cell in the tableview, using
- (UIView *)tableView:(UITableView *)tableView viewForHeaderInSection:(NSInteger)section
then, you would have 2 sections,
1. image cell
2. segment control as header, labels as the cells

deleteRowsAtIndexPaths Overlap Issue

Trying to be ios7-esque, I am inserting a UIPickerView into a UITableView when tapping on a cell in the table. This works fine and animates nicely. However, there is an issue when I retract the cell by calling deleteRowsAtIndexPaths.
I am experiencing a "bleed"/overlap where the picker is hiding one of the cells further down in the table view. See the screenshots.
I'm not doing anything super custom, so I wonder if this is an iOS7 bug. All cells have solid background colors (white).
Any help would be greatly appreciated. Thanks!
Tapping the top row
This is mid animation when retracting. Notice the overlap and the picker bleeding out over the cell at the bottom
I'm not sure why, but it looks to me like the picker cell is covering the cell below "Choose Product". If this is indeed the case, one workaround would be to explicitly set the z-order of your cells, placing the picker cell under all others:
#import <QuartzCore/QuartzCore.h>
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
UITableViewCell *cell = ...;// your logic for getting a cell
BOOL isPickerCell = ...;// your logic for identifying if this is the picker cell
cell.layer.zPosition = isPickerCell ? 0 : 1;
}
If the picker is near the bottom of the table, it could still show through below the last cell since there's nothing there to cover it. For example, if "Choose Product" were the last cell. You can work around this by inserting blank cell(s) at the bottom. This is a general problem with having cells of varying height.
After struggling with this problem, I realised that Apple's calendar application has the same issue
However, they minimise the side effects by inserting the row with a .fade animation.
tableView.insertRows(at: indexes, with: .fade)
I had similar issues (iOS 8, iPhone 6 simulator)
In my case, I had a custom cell containing a DatePicker being inserted/deleted either between Right Detail style cells or between a Right Detail style cell and the section footer, which worked as expected.
[self.table beginUpdates];
if (isVisible) {
[self.table insertRowsAtIndexPaths:#[index]
withRowAnimation:UITableViewRowAnimationMiddle];
} else {
[self.table deleteRowsAtIndexPaths:#[index]
withRowAnimation:UITableViewRowAnimationMiddle];
}
[self.table endUpdates];
But I also had Right Detail style cell being inserted/deleted between a Right Detail style cell and the end of section, which did not work as expected using the same code. The appearing/disappearing cell was visible on top of/through the cell above, and the cell moved twice as far as it should have. In the image below, People is appearing below Privacy, mid-animation.
However, I noticed that when the beginUpdates/endUpdates were commented out, the cell only moved about half a cell height instead of twice a cell height which meant that it looked much improved.
I also tried setting the zPosition which appeared to lessen the visibility when the cells overlapped.
// [self.table beginUpdates];
if (isVisible) {
[self.table insertRowsAtIndexPaths:#[index]
withRowAnimation:UITableViewRowAnimationMiddle];
} else {
cell = [self.table cellForRowAtIndexPath:peopleIndex];
cell.layer.zPosition = -1;
[self.table deleteRowsAtIndexPaths:#[peopleIndex]
withRowAnimation:UITableViewRowAnimationMiddle];
}
// [self.table endUpdates];

stop tableFooterView from animating? - iOS

I have a custom tableFooterView (it's just an 8px high CoreGraphics arc with a gradient) that I set with the tableFooterView property in viewDidLoad rather than viewForFooterInSection. When setting it with viewForFooterInSection, it floated over the content when it reached the bottom, whereas tableFooterView does what I want it to in that it stays with the UITableView's height.
But when the cells or table view do change in height, the tableFooterView animates to them slowly (about half a second but it's very noticeable). This is pretty awkward since the footer is supposed to look like an extension of the last cell. For instance, when heightForRowAtIndexPath changes the height of a cell, the tableFooterView kind of ghost-floats back. In this screenshot the bottom cell has just been shrunken to its normal size and the footer is floating back.
(As a new user I can't post images but here's the link: http://desmond.imageshack.us/Himg835/scaled.php?server=835&filename=iossimulatorscreenshotj.png&res=landing)
(This content is no longer available, 14/9/15).
It will also float over the content when the height of the last cell is suddenly changed to be larger than it was.
Any pointers? Thanks very much.
Edit: By cells changing in height, I mean through the heightForRowAtIndexPath section:
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath {
Note *currentNote = [self.notes objectAtIndex:indexPath.row];
if (currentNote.associatedCellIsSelected) {
return NORMAL_CELL_FINISHING_HEIGHT*2;
}
return NORMAL_CELL_FINISHING_HEIGHT;
}
Edit 2: In didSelectRowAtIndexPath I make the cell selected (actually the cell's note), begin / end updates as well as call reloadRow for the row that's been selected.
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
Note *currentNote = [self.notes objectAtIndex:indexPath.row];
if (currentNote.associatedCellIsSelected == FALSE) {
currentNote.associatedCellIsSelected = TRUE;
[tableView beginUpdates];
[tableView endUpdates];
}
[tableView reloadRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade]; }
I've also made sure that I get the same behavior with a plain rect redColor UIView in place of the Core Graphics footer, with the same results. I wish there was just an easy way to override the footer and tell it to not animate!

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