Programmatically highlight UITableView cell - ios

I have an iPad app which uses a UISplitViewController (with a UITableView on the left and a detail view on the right). My table view highlights the selected cell in blue when you tap on it.
When I call the following method, the cell is selected but not highlighted in blue:
[self.tableView selectRowAtIndexPath:indexPath animated:YES scrollPosition:UITableViewScrollPositionTop];
I have spent literally days fiddling about with various delegate methods and hacks trying to get the cell to highlight programatically just as if it had been tapped. I can't do it.
I've managed to almost get there with this:
- (void)tableView:(UITableView *)tableView willDisplayCell:(UITableViewCell *)cell forRowAtIndexPath:(NSIndexPath *)indexPath
{
if (shouldHighlightCell)
{
NSIndexPath *indexPathForCellToHighlight = [NSIndexPath indexPathForRow:0 inSection:0];
if ([indexPath isEqual:indexPathForCellToHighlight])
{
cell.selected = YES;
shouldHighlightCell = NO;
}
}
}
It works as long as I also have this (otherwise it remains selected even when another cell is tapped):
- (NSIndexPath *)tableView:(UITableView *)tableView willSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
NSIndexPath *ip = [NSIndexPath indexPathForRow:0 inSection:0];
if ([[self.tableView cellForRowAtIndexPath:ip] isSelected])
{
[[self.tableView cellForRowAtIndexPath:ip] setSelected:NO];
}
NSIndexPath *iToTheP = indexPath;
return iToTheP;
}
I know this is a weird and convoluted workaround. I wouldn't mind, but it doesn't even work fully. The selected cell loses its highlight if it is scrolled off screen, whereas a cell that has been tapped remains highlighted when scrolled off screen.
I'm absolutely baffled by this. I'm sure this workaround shouldn't even be necessary, that there is a much simpler solution.

Please be sure the cell's selectionStyle is UITableViewCellSelectionStyleBlue and the tableView's allowsSelection is set to YES.
The method selectRowAtIndexPath:animated:scrollPosition: works fine for me. It does highlight the selected cell.

I went through and tried all these and other solutions and no joy. In my case the problem (which drove me nuts for 2 hrs) was the following - shortly after I was calling selectRowAtIndexPath, I was calling reloadData on the tableview. That reload was wiping all the highlighting! Beware of this pitfall! With the unnecessary reloading of data call gone, the highlighting happenned as expected.

I also tried many approaches to get the initial selection to display on my single-selection UITableView. What finally worked for me was to defer the selection of the initial row until the table was set up by calling it in my UITableViewController's viewDidAppear:
override func viewDidAppear(animated: Bool)
{
tableView.selectRowAtIndexPath(indexPathToSelectInitially, animated: false, scrollPosition: .None)
}

I found this and it works for me (aka calling the delegate method didSelectRowAtIndexPath)
NSIndexPath *defaultIndexPath = [NSIndexPath indexPathForRow:0 inSection:0];
[self tableView:[self tableView] didSelectRowAtIndexPath:defaultIndexPath];
PS. I'm using UITableViewController.

I found this to be completely unfixable using all known possibilities. In the end I fixed it by ditching a lot of my code and switching to NSFetchedResultsController instead. NSFetchedResultsController was introduced shortly after I originally wrote this app, and it greatly simplifies the process of using Core Data with UITableViews.
https://developer.apple.com/library/IOs/documentation/CoreData/Reference/NSFetchedResultsController_Class/index.html

It gets the backgroundview with cell border looking like seperator.Do not change the default tableview settings in Interface builder.Make sure UITableViewCellSelectionStyleNone is NOT set to selectionstyle. I am pasting the working code. :
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{
static NSString *kCellIdentifier = #"PlayListCell";
UITableViewCell *cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:kCellIdentifier];
if (cell == nil) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:kCellIdentifier];
}
MPMediaPlaylist *playList = [playlistCollection objectAtIndex:indexPath.row];
cell.textLabel.text = playList.name;
cell.accessoryType = UITableViewCellAccessoryDisclosureIndicator;
// cell.selectionStyle = UITableViewCellSelectionStyleNone;
cell.detailTextLabel.text = [NSString stringWithFormat:#"%d Songs",[playList.items count]];
MPMediaItemCollection *playListMediaCollection = [playlistCollection objectAtIndex:indexPath.row ];
cell.imageView.image =[UIImage imageWithCGImage:[self getImageForCollection:playListMediaCollection.items]];
// the main code which make it highlight
UIView *bgColorView = [[UIView alloc] init];
bgColorView.backgroundColor = [UIColor colorWithRed:170.0f/255.0 green:170.0f/255.0 blue:170.0f/255.0 alpha:1.0f];
[bgColorView.layer setBorderColor:[UIColor blackColor].CGColor];
[bgColorView.layer setBorderWidth:1.0f];
[cell setSelectedBackgroundView:bgColorView];
return cell;
}

Related

Tableview Cell requires two taps to reveal the view

I had a problem with table view didSelect method and prepareForSegue. I used SWRevealController in my app. While selecting cell it reveals the view. Sometimes it not worked properly. It takes two taps to reveal the view. A few months back I used old reveal view frame which contains perform block action. Its worked perfectly.
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
for (int i=0; i<6; i++)
{
UITableViewCell *cell = [self tableView:tableView cellForRowAtIndexPath:[NSIndexPath indexPathForRow:i inSection:0]];
if (i == indexPath.row)
{
cell.contentView.backgroundColor = [UIColor colorWithRed:KColorRedSelected green:KColorGreenSelected blue:KColorBlueSelected alpha:1];
}
else
{
cell.contentView.backgroundColor = [UIColor colorWithRed:KColorRed green:KColorGreen blue:KColorBlue alpha:1];
}
}
}
Add this code inside of didSelectRowAtIndexPath and didDeselectRowAtIndexPath functions
dispatch_async(dispatch_get_main_queue(), ^{
//Write code what you need
});
That works for me.
The problem is with this line
[self tableView:tableView cellForRowAtIndexPath:[NSIndexPath indexPathForRow:i inSection:0]];
You are calling the delegate method, which dequeues a reusable cell (I assume, since it's standard behavior). You do not want to dequeue a reusable cell, you want to do something with a cell that is currently displayed at indexPath. To do that use method from UITableView
[tableView cellForRowAtIndexPath:indexPath];
The full code
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
// grab the selected cell and give it selected color
UITableViewCell *cell = [tableView cellForRowAtIndexPath:indexPath];
cell.contentView.backgroundColor = [UIColor colorWithRed:KColorRedSelected green:KColorGreenSelected blue:KColorBlueSelected alpha:1];
}
- (void)tableView:(UITableView*)tableView didDeselectRowAtIndexPath:(NSIndexPath*)indexPath
{
// grab the deselected cell (if it's still visible) and give it deselected color
UITableViewCell *cell = [tableView cellForRowAtIndexPath:indexPath];
cell.contentView.backgroundColor = [UIColor colorWithRed:KColorRed green:KColorGreen blue:KColorBlue alpha:1];
}
You will also need to set appropriate color in UITableViewDelegate method cellForRowAtIndexPath, since the color you once set will stay in the cell when it's reused.
This s completely wrong method to get clicked cell
UITableViewCell *cell = [self tableView:tableView cellForRowAtIndexPath:[NSIndexPath indexPathForRow:i inSection:0]];
And don't use for loop as well. instead of this you should use
UITableViewCell *cell = [tableView cellForIndexPath:indexPath];
to get correct cell.

UITableView ScrollToRowAtIndexPath method not working

I have a UITableView as a subview of a View. In the ViewController when the table is being populated I'm highlighting one of the rows and keeping a record of the indexPath for that row. I'm doing this in the cellforRowAtIndexPath method.
-(UITableViewCell *) tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{
favouriteCellView *cell = [tableView dequeueReusableCellWithIdentifier:#"reuseID"];
QBCOCustomObject *favouriteObject = [_favouriteResults objectAtIndex:indexPath.row];
if (favouriteObject.userID == self.user.ID) {
UIView *bgColor = [[UIView alloc] init];
bgColor.backgroundColor = [UIColor colorWithRed:173.0f/255.0f green:146.0f/255.0f blue:237.0f/255.0f alpha:.5];
self.highlightedRowIndex = indexPath;
[cell setSelectedBackgroundView:bgColor];
[tableView selectRowAtIndexPath:indexPath animated:NO scrollPosition:UITableViewScrollPositionMiddle];
}
return cell;
}
Then in the viewDidAppear Method I want the table to scroll to the highlighted cell.
-(void)viewDidAppear:(BOOL)animated{
[self.tableView scrollToRowAtIndexPath:self.highlightedRowIndex atScrollPosition:UITableViewScrollPositionTop animated:YES];
}
However I've double checked that the method is being hit with a breakpoint, but unfortunately the highlighted row is not being scrolled to the top of the table as I'd expected. AM I misunderstanding the scrollToRowAtIndexPath method? Or have I left something out of the above code.
If the row is not on screen, it will not yet be loaded by the table view. This means your cellForRowAtIndexPath for that cell will not yet be called. You'll want to choose this index in a way that does not depend on the view loading. Try this before you call scrollToRowAtIndexPath:
NSInteger row = 0;
for (QBCOCustomObject *object in _favouriteResults) {
if (object.userID == self.user.ID) break;
row++;
}
self.highlightedRowIndex = [NSIndexPath indexPathForRow:row inSection:0];

Having problems with the method: prepareForReuse

I have a custom UITableViewCell, and when it's selected, it expands and adds a UILabel to the selected cells UIView that I added in the storyBoard.
When I run the app and select a cell, the label gets added to myView as expected. The problem is, when I scroll down, the label is also shown at another cell.
Apparently the reason its behaving like so, is because I'm reusing the cell and I don't clean them as Emilie stated. I'm trying to call the method of prepareForReuse and 'cleaning' the cell, but I'm having trouble doing that. Here is my code:
- (void)prepareForReuse {
NSArray *viewsToRemove = [self.view subviews];
for (UILablel *v in viewsToRemove) {
[v removeFromSuperview];
}
Doing that, cleans even the selected cells label.
- (void)viewDidLoad {
self.sortedDictionary = [[NSArray alloc] initWithObjects:#"Californa", #"Alabama", #"Chicago", #"Texas", #"Colorado", #"New York", #"Philly", #"Utah", #"Nevadah", #"Oregon", #"Pensilvainia", #"South Dekoda", #"North Dekoda", #"Iowa", #"Misouri", #"New Mexico", #"Arizona", #"etc", nil];
self.rowSelection = -1;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
CategorieCell *customCell = [tableView dequeueReusableCellWithIdentifier:#"cellID" forIndexPath:indexPath];
customCell.title.text = [self.sortedDictionary objectAtIndex:indexPath.row];
return customCell;
}
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
[tableView deselectRowAtIndexPath:indexPath animated:YES];
CategorieCell *customCell = (CategorieCell *)[tableView cellForRowAtIndexPath:indexPath];
if (self.info) {
[self.info removeFromSuperview];
}
self.info = [[UILabel alloc] init];
[self.info setText:#"Hello"];
[self.info setBackgroundColor:[UIColor brownColor]];
CGRect labelFrame = CGRectMake(0, 0, 50, 100);
[self.info setFrame:labelFrame];
[customCell.infoView addSubview:self.info];
NSLog(#"%ld", (long)indexPath.row);
self.rowSelection = [indexPath row];
[tableView beginUpdates];
[tableView endUpdates];
}
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
if ([indexPath row] == self.rowSelection) {
return 159;
}
return 59;
}
The answer is quite simple : you reuse your cell like you should, but never clean them
Reusing your UITableViewCell means that the cell you clicked on previously will be reused when it will go off-screen.
When clicked, you add a view to your UITableViewCell. When reused, the view is still there because you never remove it.
You have two choices : One, you could set a tag of the self.info view (or check with the indexpath you're keeping in memory), then check when you dequeue the cell if the info view is there, and remove it. The cleaner solution would be to implement the view removal by overriding the prepareForReuse method of your custom UITableViewCell
Precision
The first thing you need to do is set a tag for your self.info view after initializing it:
[self.info setTag:2222];
If you want to keep it as simple as possible, you could check and remove the self.info view directly in your cellForRowAtIndexPath method :
CategorieCell *customCell = [tableView dequeueReusableCellWithIdentifier:#"cellID" forIndexPath:indexPath];
customCell.title.text = [self.sortedDictionary objectAtIndex:indexPath.row];
if [customCell.infoView viewWithTag: 2222] != nil {
[self.info removeFromSuperview]
}
return customCell;
I am not a percent sure this code compiles, I cannot test it on my side for now. Hope it works !

How to add ActivityIndicator on Custom TableviewCell's button click?

I have problem with my custom tableview cell button click event with load activity indicator on selected cells button.
If you have link or other source then please help me out.
I am new in iOS development.
This is significantly easier because it doesn't involve any third party stuff (even though MBProgressHUD is a great tool). When I created the cell, I created a UIACtivityIndicatorView and added it as the cell's accessoryView. Later, when a row is pressed, I grab a reference to the cell itself at the appropriate indexPath, and then access its accessoryView property, which is the indicator view. From there you can just tell it to start animating.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:#"cell"];
if (cell == nil) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:#"cell"];
UIActivityIndicatorView *activityIndicator = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
cell.accessoryView = activityIndicator;
}
cell.textLabel.text = _items[indexPath.row];
return cell;
}
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
// deselect the row if you want the cell to fade out automatically after tapping
[tableView deselectRowAtIndexPath:indexPath animated:YES];
// get a reference to the cell that the user tapped
UITableViewCell *cell = [tableView cellForRowAtIndexPath:indexPath];
// get the tapped cell's accessory view and cast it as the activity indicator view
UIActivityIndicatorView *activityIndicator = (UIActivityIndicatorView *)cell.accessoryView;
// tell it to start animating
[activityIndicator startAnimating];
}
This results in the following after tapping the first cell:
You'll have to change the code a bit depending on when/how you want to stop the activity indicator from spinning, but without have more information from you this is the best info I can provide. You'll likely want to add the indexPath.row integer to the progressView's tag property, but there's a bit more to that. Hope this helps!
EDIT
Add a tag to the button that's the indexPath of the row, and do something like:
- (void)showProgressViewForButton:(id)sender {
NSInteger tappedCellIndex = sender.tag;
NSIndexPath *indexPath = [NSIndexPath indexPathForRow:tappedCellIndex inSection:0];
UITableViewCell *cell = [self.tableView cellForRowAtIndexPath:indexPath];
UIActivityIndicatorView *activityIndicator = (UIActivityIndicatorView *)cell.accessoryView;
[activityIndicator startAnimating];
}
here is the link for MBProgressHUD:
https://github.com/jdg/MBProgressHUD

Expanding and Collapsing table view cells in ios

I have a table view of custom cells and some buttons in each cell.Clicking on any of the button inside the cell will reveal another custom view below that cell.Next click on the same button will collapse the view and need this same for all cells.I tried with insertrow method on the button click but in vain.How can i do this with using only the table view delegates.
This is what i tried:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *simpleTableIdentifier = #"CustomCell_For_Dashboard";
CustomCellFor_Dashboard *customCell = (CustomCellFor_Dashboard *)[tableView dequeueReusableCellWithIdentifier:simpleTableIdentifier];
if (customCell == nil)
{
NSArray *nib = [[NSBundle mainBundle] loadNibNamed:#"CustomCellFor_Dashboard" owner:self options:nil];
customCell = [nib objectAtIndex:0];
}
[customCell.howyoulfeelBtn addTarget:self action:#selector(buttonclicked:) forControlEvents:UIControlEventTouchUpInside];
customCell.nameLabel.text = #"test";
customCell.imgView.image = [UIImage imageNamed:#"Default.png"];
// customCell.prepTimeLabel.text = [prepTime objectAtIndex:indexPath.row];
return customCell;
}
-(void)buttonclicked:(id)sender{
NSIndexPath *indexPath = [myTable indexPathForCell:sender];
[myTable beginUpdates];
NSIndexPath *insertPath = [NSIndexPath indexPathForRow:indexPath.row inSection:indexPath.section];
[myTable insertRowsAtIndexPaths:[NSArray arrayWithObject:insertPath] withRowAnimation:UITableViewRowAnimationTop];
}
can anyone help me?
I got the same task on one project with just one thing different: There were no buttons, just tapping on cell will expand or collapse it.
There are several things you should edit in your code. First, the button method code will look something like this:
- (void) collapseExpandButtonTap:(id) sender
{
UIButton* aButton = (UIButton*)sender; //It's actually a button
NSIndexPath* aPath = [self getIndexPathForCellWithButtonByMagic:aButton];
//expandedCells is a mutable set declared in your interface section or private class extensiont
if ([expandedCells containsObject:aPath])
{
[expandedCells removeObject:aPath];
}
else
{
[expandedCells addObject:aPath];
}
[myTableView beginEditing];
[myTableView endEditing]; //Yeah, that old trick to animate cell expand/collapse
}
Now the second thing is UITableViewDelegate method:
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
if ([expandedCells containsObject:indexPath])
{
return kExpandedCellHeight; //It's not necessary a constant, though
}
else
{
return kNormalCellHeigh; //Again not necessary a constant
}
}
Key thing here is to determine if your cell should be expanded/collapsed and return right height in delegate method.
Going off of what #eagle.dan.1349 said, this is how to do it on the clicking of the cell. In storyboard, you also need to set the table cell to clip subviews, otherwise the content that would be hidden will show.
.h
#property (strong, nonatomic) NSMutableArray *expandedCells;
.m
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
if ([self.expandedCells containsObject:indexPath])
{
[self.expandedCells removeObject:indexPath];
}
else
{
[self.expandedCells addObject:indexPath];
}
[tableView beginUpdates];
[tableView endUpdates];
}
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
CGFloat kExpandedCellHeight = 150;
CGFloat kNormalCellHeigh = 50;
if ([self.expandedCells containsObject:indexPath])
{
return kExpandedCellHeight; //It's not necessary a constant, though
}
else
{
return kNormalCellHeigh; //Again not necessary a constant
}
}
Saw this post and just wanted to give my 2 cents as my solution to this is very similar to the chosen answer (the tapping of a whole area).
Many people architect this by using just cells alone, but I believe there is a way to build this that might align better with what people are trying to achieve:
There are headers and there are cells. Headers should be tappable, and then cells underneath the headers would show or hide. This can be achieved by adding a gesture recognizer to the header, and when tapped, you just remove all of the cells underneath that header (the section), and viceversa (add cells). Of course, you have to maintain state of which headers are "open" and which headers are "closed."
This is nice for a couple of reasons:
The job of headers and cells are separated which makes code cleaner.
This method flows nicely with how table views are built (headers and cells) and, therefore, there isn't much magic - the code is simply removing or adding cells, and should be compatible with later versions of iOS.
I made a very simple library to achieve this. As long as your table view is set up with UITableView section headers and cells, all you have to do is subclass the tableview and the header.
Link: https://github.com/fuzz-productions/FZAccordionTableView
I also had a same situation and my solution was to put a button on top of the Section Title with viewForHeaderInSection method.
noOfRows defines how many rows are there in each section and button.tag keeps which button of section is pressed.
- (UIView *)tableView:(UITableView *)tableView viewForHeaderInSection:(NSInteger)section {
UIButton *btnSection = [[UIButton alloc] initWithFrame:CGRectMake(0, 0, tableView.frame.size.width, tableView.frame.size.height)];
btnSection.tag = section;
[btnSection setTitle:[sectionArray objectAtIndex:section] forState:UIControlStateNormal];
[btnSection addTarget:self action:#selector(sectionButtonTapped:) forControlEvents:UIControlEventTouchUpInside];
return btnSection;
}
- (void)sectionButtonTapped:(UIButton *)button {
sectionIndex = button.tag;
if (button.tag == 0) {
noOfRows = 3;
} else if (button.tag == 1) {
noOfRows = 1;
} else if (button.tag == 2) {
noOfRows = 2;
}
[self.tableView reloadData];
}
Hope this will help you..

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