tvOS UITableView scroll to cell - objective-c

I'm starting a new project for tvOS. I have created a programmatically UITableView inside my viewcontroller. Inside the UITableView i have created 5 cells. Until now everything works, but the problem happens when i'm trying to programmatically scroll to cell 4 so i'm doing:
NSIndexPath *indexPath = [NSIndexPath indexPathForRow:3
inSection:0];
[tableView scrollToRowAtIndexPath:indexPath
atScrollPosition:UITableViewScrollPositionTop
animated:YES];
But the code above does nothing. It always start at first cell and highlight it as the selected one. I want to be able to programmatically start at another cell and it most be highlight so when i use the arrow keys down or up it scroll from there and not first cell. Please help me in doing that

You should do next:
In viewController that respond for UITableView, implement next function:
- (UIView *)preferredFocusedView {
return self.tableView;
}
where tableView is your table, and after that, override next function
- (NSIndexPath *)indexPathForPreferredFocusedViewInTableView:(UITableView *)tableView {
return [NSIndexPath indexPathForRow:_exerciseIndex inSection:0];
}
where _exerciseIndex index that you need to focus.

Related

UITable view selection stay highlighted

I am using XCode4.2 to develop a storyboard application
I am switching views based on a click in a UITableView after clicking the row is highlighted in blue and the new view is loaded .
when I come back to the original view the row is still highlighted in blue ... how can I disable that ?
I do this in
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
[tableView deselectRowAtIndexPath:indexPath];
}
That way I have the index path that was selected every time.
use deselectRowAtIndexPath:(NSIndexPath *)indexPath animated:(BOOL)animated function to deselect rows in uitableview
call it in your viewWillAppear function
[yourTableView deselectRowAtIndexPath:selectedIndexPath animated:NO];
if you are not sure which is index you select last time you can run a loop on all the index path in your table.
-(void) viewWillAppear:(BOOL)animated{
[super viewWillAppear:animated];
for(int i = 0; i <= [yourArr count]; i++)
{
NSIndexPath *indexPath = [NSIndexPath indexPathForRow:i inSection:0];
[yourTableView deselectRowAtIndexPath:indexPath animated:NO];
}
}
Note: As I don't know your exact code....you need to modify above code to your needs.
A UITableViewController does this automatically. Otherwise, in your viewDidAppear for the owning controller, you need to call - (void)deselectRowAtIndexPath:(NSIndexPath *)indexPath animated:(BOOL)animated on the table view.

UITableView Center Cell Details

I am trying to sync a UITableView with a UILabel to make sure they show the same data; of course, things will be different in the end, but for testing this is what I need to do.
See the arrow? I want that middle cell (from px44-88) to show the cell.textLabel.text in a UILabel when it is the "middle cell".
I tried using - (void)tableView:(UITableView *)tableView willDisplayCell:(UITableViewCell *)cell forRowAtIndexPath:(NSIndexPath *)indexPath but I was having so many problems I figured I'd come here to ask if anyone has a better way of doing this. I'm not sure if it would make a difference or not but I am using NSFetchedResultsController to populate my UITableView.
UITableView is a subclass of UIScrollView, so probably you can use UIScrollViewDelegate
- (void)scrollViewDidScroll:(UIScrollView *)scrollView
member to detect which cell is currently in the middle.
I.e. assuming you have a plain table with no sections, and tableView is an outlet for the table, label is an outlet for the label, than this will function in your controller will work:
- (void)scrollViewDidScroll:(UIScrollView *)scrollView {
int row = (scrollView.contentOffset.y + tableView.frame.size.height / 2) / 44;
NSIndexPath *indexPath = [NSIndexPath indexPathForRow:row inSection:0];
UITableViewCell *cell = [tableView cellForRowAtIndexPath:indexPath];
label.text = cell.textLabel.text;
}
Of course, you need to do some scrolling to make it work ;)
You can use visibleCells method to get layout of visible cells for non-plain table and use it to detect cell in the middle of the table.

NSIndexPath of UITableViewCell subview?

Is there any was to get the NSIndexPath of a UITableViewCell's contentView subview?
In my case, I have a table view in which each row is split into 3 buttons. I can use the button tag to keep track of which column it is but I also need to know what row of the table view it is a subview of (when the user taps the button).
Because the button blocks the entire actual table view row, didSelectRowAtIndexPath is never called (which is expected), so I can't get it that way.
I have tried just [thisButton superview] but that doesn't seem to work. Any thoughts?
I assume the button is sending its UIControlEventTouchUpInside event message to your view controller? Then you could do something like:
- (void)buttonPressed:(UIButton *)button
{
CGPoint location = [button.superview convertPoint:button.center toView:self.tableView];
NSIndexPath *indexPath = [self.tableView indexPathForRowAtPoint:location];
[self doSomethingWithRowAtIndexPath:indexPath];
}
One possible option is when making the cell for index path you can assign the tag to be 3 * row_number + <the tag number>. then just divide the tag by 3 to get the row and %3 to get the button.
You don't need to call button.superview. You can go straight from any subview in the tree right to the table view
Objective-C
- (NSIndexPath *)indexPathForCellContainingView:(UIView *)view inTableView:(UITableView *)tableView {
CGPoint viewCenterRelativeToTableview = [tableView convertPoint:CGPointMake(CGRectGetMidX(view.bounds), CGRectGetMidY(view.bounds)) fromView:view];
NSIndexPath *cellIndexPath = [tableView indexPathForRowAtPoint:viewCenterRelativeToTableview];
return cellIndexPath
}
Swift
func indexPathForCellContainingView(view: UIView, inTableView tableView:UITableView) -> NSIndexPath? {
let viewCenterRelativeToTableview = tableView.convertPoint(CGPointMake(CGRectGetMidX(view.bounds), CGRectGetMidY(view.bounds)), fromView:view)
return tableView.indexPathForRowAtPoint(viewCenterRelativeToTableview)
}

Return NSIndexPath from custom cell ? (UITableView)

I need to get the NSIndexPath for a custom cell in a UITableView. Here's the problem: I send a NSNotification from my custom cell to my UITableViewController when editingDidBegin gets called from a UITextField in my custom cell. In my UITableViewController, I resize the UITableView when the UITextField began editing, and then want the table view to scroll to the Cell in which the UITextField is first responder. But I can't figure out how to return the indexPath of the cell where the UITextField is being edited. I have tried so many ways, but its still not working. One way is this: in my cstomCell class i select the row using [self setSelected:YES] and in my TV controller then if I NSLog the row of [self.tableV indexPathForSelectedRow] it always returns 0 even though its always not 0.
Just give the cell a value for its tag property. Then you can get that cell by calling this
UITableViewCell *cell = (UITableViewCell *)[self.tableView viewWithTag:tagValue];
then once you have the cell you can get the NSIndexPath like this
NSIndexPath *indexPath = [self.tableView indexPathForCell:nextResponderCell];
Since you have a UITextField in your custom cell you can place cell.textField.delegate = self; in the
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
data source method. That way you will not have to setup a NSNotification in the Custom Cell. Also in this same method you can tag both your cells text field like this cell.textField.tag = indexPath.row; and the cell like this cell.tag = indexPath.row;
Now that you have set the UITextField delegate, you can now place this method in your UITableViewController class
- (void)textFieldDidBeginEditing:(UITextField *)textField {
CustomCell *cell = (CustomCell *)[self.tableView viewWithTag:textField.tag];
NSIndexPath *indexPath = [self.tableView indexPathForCell:cell];
}
The above UITextField delegate method should get you the indexPath for the cell you have currently selected.
try this code..
- (void)textFieldDidBeginEditing:(UITextField *)textField
{
UITableView *tableView;
UITableViewCell* superViewCell = [self returnSuperCellViewOfTextField:textField];
if(superViewCell)[tableView scrollToRowAtIndexPath:[tableView indexPathForCell:superViewCell] atScrollPosition:UITableViewScrollPositionMiddle animated:YES];
}
-(id)returnSuperCellViewOfTextField:(id)viewToCheck
{
id superView = [viewToCheck superview];
if([viewToCheck isKindOfClass:[UITableViewCell class]] && superView)return superView;
else if(([viewToCheck respondsToSelector:#selector(superview)] && superView)) return [self returnSuperCellViewOfTextField:superView];
return nil;
}
Does this (your answer that you gave before below)still works if you have multiple texfields in each cell?:
UITableViewCell *cell = (UITableViewCell *)[self.tableView viewWithTag:tagValue];
then once you have the cell you can get the NSIndexPath like this
NSIndexPath *indexPath = [self.tableView indexPathForCell:nextResponderCell];
Since you have a UITextField in your custom cell you can place cell.textField.delegate = self; in the
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
data source method. Also in this same method you can tag both your cells text field like this cell.textField.tag = indexPath.row; and the cell like this cell.tag = indexPath.row;
Now that you have set the UITextField delegate, you can now place this method in your UITableViewController class
- (void)textFieldDidBeginEditing:(UITextField *)textField {
CustomCell *cell = (CustomCell *)[self.tableView viewWithTag:textField.tag];
NSIndexPath *indexPath = [self.tableView indexPathForCell:cell];
I have a tableview with 8 cells, and in each cell i have 6 texfields, and also the tableview is dynamic, so the user can insert more cells...but i´m having trouble in how to save the text the user enters in each texfield. Is it possible that with "cell.textField.tag = indexPath.row", the controller identify´s the texfield i´m in?
I like to tag my cells like so:
/* Create a tag based on the section and row of a cell(used to retrive the cell for the beginEditingNextCell method. */
-(NSInteger)tagForIndexPath:(NSIndexPath*)path {
return path.section * 1000 + path.row + 1;
}
The other way is to pass the beginEditing data using a custom delegate, and include a cell model, which you can then use to figure out your path depending on how you are storing data.
Check out my github project, it has the code to handle this case, as well as resizing for the keyboard and tabbing to the next editable cell: https://github.com/andrewzimmer906/XCell

-[UITableView scrollToRowAtIndexPath:] scrolls, but goes back to 1st row

I have a grouped table view with textfields in the tableview. For the keyboard to not hide the textfields, in the textFieldShouldBeginEditing, I am calling the scrollToRowAtIndexPath method and setting the scroll position of the row being edited to the top of the tableview.
The scrolling does happen, but as soon as the keyboard appears (ie as soon as the textFieldShouldBeginEditing returns YES), the table scrolls back to its original position and displays the first row of the first section on top. I am not calling reloadTable after making a call to scrollToRowAtIndexPath.
The problem occurs only for row 4 and 5 (bdate and zip) password2 works as expected.
This is the code I am using to scroll to a particular row
if(textField == password2){
indPath = [NSIndexPath indexPathForRow:3 inSection:0];
[self.tableView scrollToRowAtIndexPath:indPath atScrollPosition:UITableViewScrollPositionTop animated:YES];
return YES;
}
else if(textField == bdate){
indPath = [NSIndexPath indexPathForRow:4 inSection:0];
[self.tableView scrollToRowAtIndexPath:indPath atScrollPosition:UITableViewScrollPositionTop animated:YES];
return YES;
}
else if(textField == zip){
indPath = [NSIndexPath indexPathForRow:5 inSection:0];
[self.tableView scrollToRowAtIndexPath:indPath atScrollPosition:UITableViewScrollPositionTop animated:YES];
return YES;
}
Can someone please tell me what could be going wrong? Any insight would help.
Thanks
I suspect what is going on is that the table view is rubber banding back, just like a webview in Safari does when you run pass its bounds. The most likely reason for this is that when you pop up the keyboard it is on top of the table view, but the table view has not physically contracted, thus all the UITableViewCells fit within the partially obscured UITableView, and when some of them scroll off it rubber bands so they all are within it.
In order to test this try reducing the size of the list view so that you can see the whole thing when the keyboard is displayed, if the bug goes away you want to write code that dynamically changes the size as the keyboard animates in and out.
//For iOS 7
[self.TableView reloadData];
NSIndexPath *indexPat = [NSIndexPath indexPathForRow:1 inSection:1];
[self.TableView scrollToRowAtIndexPath:indexPat atScrollPosition:UITableViewScrollPositionTop animated:YES];