Why are my UITableViewCells resizing after selecting an item? - ios

I have a TableViewController with each cell potentially having multiple lines of text (up to 3). In cellForRowAtIndexPath I am setting the cell for wrap and any number of lines. As a result, the cells successfully display wider when there are three or more lines of text (the default size allows only 2 lines of text).
(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:#"cell" forIndexPath:indexPath];
Request *request = self.tableRequests[indexPath.row];
cell.textLabel.lineBreakMode = NSLineBreakByWordWrapping;
cell.textLabel.numberOfLines = 0;
cell.textLabel.text = request.question;
However, if I select a cell and go to the next view controller, when I return all the cells have reverted to a size which allows only 2 lines of text. I do not have an unwind segue; I am just using the back button as provided by the navigation controller.
When I watch closely, I believe the table actually collapses to its original cell sizes straight after selecting a cell, momentarily before the view is replaced by the subsequent view controller.
How do I make the table retain the cell size?

Related

Duplicate rows on uitableview when scrolling with custom cell

Here is my code :
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
NSString *cellIdentifier=#"menucell";
MenuCell *cell = (MenuCell*) [tableView dequeueReusableCellWithIdentifier:cellIdentifier forIndexPath:indexPath];
if (cell==nil)
cell= [[MenuCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cellIdentifier] ;
MenuModel *resturntent = (self.menuList)[indexPath.row];
cell.foodNameLbl.text = resturntent.MenuName;
cell.priceLbl.text = [NSString stringWithFormat:#"%# %#",#"$" , resturntent.MenuRate];
cell.foodImage.image = [UIImage imageNamed:#"full_breakfast.jpg"];
return cell;
}
While scrolling uitextfields values gets duplicates .
I need help to fix this issues
When you use dequeueReusableCellWithIdentifier, your cells will be reused. This means when the user scrolls the tableview, a cell which moves out of the screen will be reused to display the contents of a cell which is about to move onto the screen.
Even though this helps in saving memory, the problem it causes is the that the cell needs to be prepared for display before it is loaded with the content of the new cell.
In your case, it seems you need to maintain the values the user has entered in a textfield of a cell.
So to fix your problem, if there are not that many cells in the tableview, simply stop reusing the cell. Else whenever the user enters a value in the textfield of a cell, save it in an array (array of 'MenuModel' in your case). And fetch the value from from the model and set it to your textfield in the cellForRowAtIndexPath method like your have set values for other labels.

iOS Images display abnormally in UITableView

I'm trying to put some images into a UITableView, so I put an Image View into the UITableViewCell and set it aspect fit.
After starting the simulator, it appears to be right, but when I click at one cell or scroll out the originally hidden cells(may be the reused ones), the image breaks the limit of the image view's setting and destroys the layout.
the middle picture is normal, but the upper or lower one is out of shape.
cellForRowAtIndexPath function as follow:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"ShangbaoOriginCell";
ShangbaoOriginCellTableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
cell.newsSampleLabel.text = [NSString stringWithFormat:NSLocalizedString(#"Cell %d",), indexPath.row];
cell.cellView.contentMode = UIViewContentModeScaleAspectFit;
cell.imageView.contentMode = UIViewContentModeScaleAspectFit;
cell.imageView.image = self.tableItems[indexPath.row];
return cell;
}
whether cell.imageView.contentMode is set or not, this problem exists.
I've added bg color, ImageView is black, Content View is blue, Cell is green.
So I saw incredible thing, the (table view) cells become not wide enough (you can see from the narrow gap between two pictures). Which is set properly in story board that the cell's width cover the whole screen.
I forgot to say that this table view is in a tabbed application, but I think this doesn't matter . And this time I have added constraints to the image view, but in vain.

self.tableView reloadData is not working to vertically center my label text

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"MyCell";
MyCustomCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];
if (cell == nil)
cell = [[MyCustomCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
Movie *movie = [self.movies objectAtIndex:indexPath.row];
cell.title.text = movie.title;
cell.subtitle.text = movie.subtitle;
cell.subtitle.numberOfLines = 0;
[cell.subtitle sizeToFit];
return cell;
}
I am calling reloadData from two places. One is from the end of a loadInitialData function, which is called from viewDidLoad.
A second one is being called from viewDidAppear, although this is inconsequential to my problem, because it existed before it and exists without it.
I initially load 3 rows of sample data, with titles and subtitles. Now what happens is my subtitle text is vertically centered when this window first launches. If I grab the table and scroll is high up, all of a sudden my [cell.subtitle sizeToFit] goes into action, and my text goes to the top vertically, which is desired.
So my issue is... why is the text vertically centered from the beginning? reloadData doesn't work either. When I return from adding a new row, all rows but the newly added row are vertically aligned to top as they should. The new row is incorrectly vertically centered.
Why doesn't this work? Everything seems good. New data is added etc. Via NSLog statements, I have verified numberOfRowsInSection is immediately called after reloadData is called.
So why does the aligning of the text vertically to the top not work?
Thanks!
This is probably because the UITableViewCell has not yet been layed out and so it does not have a size yet. Try doing the sizeToFit in this UITableViewDelegate method
- (void)tableView:(UITableView *)tableView willDisplayCell:(UITableViewCell *)cell forRowAtIndexPath:(NSIndexPath *)indexPath
I am not sure this will work, but it worth trying.
Add [cell setNeedsLayout]; before you return the cell so it will layout the cell before presentation.

Dynamic sized labels inside a table not refreshing in ios

My table has cells which have several labels. I want one of these labels to fit its size so text begins right below the Title (remember that Labels align text vertically unless you fit its container).
Problem is, the very first time the table is loaded all labels' texts are succesfully populated but label sizes don't actually graphically apply until the NEXT time a refresh is asked. (if I ask for a reloadData with the exact same information, the labels' sizes work flawlessly).
This is some of my cellForRowAtIndexPath code:
cell.body.text = user.message;
[cell.body sizeToFit];
The only solution I've found so far is double calling [table reloadData] but this is an ugly solution. Any way I can fix this?
Edit: Previous code was a summary, I'll show the whole code here as requested:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
TwitterTweetCell *cell = [tableView dequeueReusableCellWithIdentifier:#"TwitterTweetCell"];
// Populate cell
TweetModelData *tweet = [self.twitterModelData.tweets objectAtIndex:[indexPath item]];
cell.tweetName.text = tweet.user;
cell.tweetChannel.text = tweet.userName;
cell.tweetBody.text = tweet.message;
[cell.tweetBody sizeToFit];
return cell;
}
Regarding cell size, everything is working ok. Depending on the size of the message each cell has a different size which was pre-calculated before.
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
return ((TweetModelData *)[self.twitterModelData.tweets objectAtIndex:[indexPath item]]).tweetHeight + 30.0f;
}
I finally found it. Don't know the reason, but it seems disabling "Use autolayout" on my storyboard fixed it.
I'm guessing auto-layout was overwriting the layout changes I was applying so they had no effect until the next data reload.

UITableview cell subview larger height then cell

#All Hello
Its quite interesting problem i have.
Actually i have subviews which can be larger in height then cell height itself (Its required for my design). For example cell "A" height is 40 while subview height= 70.
I can show larger subview but when the cell A goes off the screen (i scroll to top) then its subview also disappear (Obvious) result. But that gives undesired effect as larger subview which before extends to cell say "B" beneath container cell suddenly disappear.
I have tried to set cell background as transparent in willDisplayCell delegate method but no luck.
Below is my related method if anyone wants to see
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *MyIdentifier = #"MyIdentifier";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:nil];
if (cell == nil)
{
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault
reuseIdentifier:MyIdentifier] autorelease];
cell.selectionStyle = UITableViewCellSelectionStyleNone;
}
NSArray *newArray = [[dataDictionary allKeys] sortedArrayUsingSelector: #selector(compare:)];
[cell.contentView addSubview: [[[dataDictionary objectForKey:[newArray objectAtIndex:indexPath.section]] objectForKey:#"DayView"] objectAtIndex:indexPath.row]];
return cell;
}
Pardon me if i am not very much clear but this is best i can explain my situation.
I want to show views like http://postimg.org/image/e5ok5hybl/ image.
If you must do this, you can use a simple trick:
Move the y-origin of the table to a negative value equal to the amount your view extends below the cell, e.g. origin -30px.
Make the table height taller by the same amount, i.e. make it 30px taller.
Increase the top content inset of the table by the same amount, i.e. increase by 30px.
What you've effectively done is extend the table view off-screen while maintaining the original position of the cells. Since the table view extends off-screen, the cell will not be dequeued until the part that extends below the cell has scrolled off screen.
Here is a sample project demonstrating the trick.

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