Reasons for UITableViewCell UI inconsistency - ios

Most of the time, when my app is working the way it should, my Table View items look like this:
But every so often a cell (on initial load) looks likes this:
As you can see the image has resized, the 'published By' label has resized.
Why would this happen? The same code/storyboard should affect all the cells the same way? Why are some not doing what they are told?
If it helps, when a cell loads the wrong way, all I have to do is scroll up, and back down again, and the problem is fixed !!
This means that there clearly isn't a problem with the image or the amount of text, is it just the iPhone acting up?
Thanks for any help !

I think its cell dequeue issue. Your cell could not calculate proper height for cell. If you are using autolayout try the following code. hope it will works for you.
-(CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
static YOUR_TABLEVIEW_CELL *sizingCell = nil;
static NSString *CellIdentifier=#"YOUR_TABLEVIEW_CELL_IDENTIFIER";
sizingCell =[tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (sizingCell==nil)
{
sizingCell=[[YOUR_TABLEVIEW_CELL alloc]initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
}
[self configureFareIssueCell:sizingCell atIndexPath:indexPath];
return [self calculateHeightForConfiguredSizingCell:sizingCell];
}
//assign all the lables & images here
- (void)configureFareIssueCell:(YOUR_TABLEVIEW_CELL* )cell atIndexPath:(NSIndexPath *)indexPath
{
//e.g
cell.lbl.text=#"YOUR_TEXT";
cell.imageView.image=[UIImage imageNamed:#"NAME_OF_YOUR_IMAGE"];
}
- (CGFloat)calculateHeightForConfiguredSizingCell:(YOUR_TABLEVIEW_CELL *)sizingCell
{
CGSize size = [sizingCell.contentView systemLayoutSizeFittingSize:UILayoutFittingCompressedSize];
return size.height + 1.0f; // Add 1.0f for the cell separator height
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier=#"YOUR_TABLEVIEW_CELL_IDENTIFIER";
YOUR_TABLEVIEW_CELL *cell =[tableView dequeueReusableCellWithIdentifier:#"YOUR_TABLEVIEW_CELL_IDENTIFIER"];
if (cell==nil)
{
cell=[[YOUR_TABLEVIEW_CELL alloc]initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
}
[self configureFareIssueCell:cell atIndexPath:indexPath];
return cell;
}

Do you use layer mask for creating rounded image? If yes, you see this strange behavior because layer mask was created before UITableView assign proper frame for cell, so layer mask will have incorrect frame.

Related

Why the UITableViewCell changed its size when I slide the view

I am a beginner in iOS development. I face a problem where I need little help.
I wrote a small program to learn custom UITableViewCell. It just works well at beginning; after that, when I slide the view, it changes size of the cell. I am confused about where I might be going wrong. The ContentView have only one view which is UIImageView.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
HWHomePageCell *cell = [tableView dequeueReusableCellWithIdentifier:#"HWHomePageCell"];
if (cell == nil)
{
cell = [HWHomePageCell homePageCell];
}
cell.imageView.image = [UIImage imageNamed:#"XD"];
return cell;
}
These are the pictures. Top two are good, but when I slide down, as you can see, the 3rd doesn't work well
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
HWHomePageCell *cell = [tableView dequeueReusableCellWithIdentifier:#"HWHomePageCell"];
cell = [HWHomePageCell homePageCell];
cell.imageView.image = [UIImage imageNamed:#"XD"];
return cell;
}
When you use custom cell then no need to check whether cell is nil or not. so please remove this condition and implement it.
cell.imageView.contentMode = UIViewContentModeScaleAspectFill;

how to make Dynamically Cell size Adjustment According to UIlabel text size

I am Beginner to iOS, I was facing problem , How to make Custom Cell size is Adjusted to UILabel Size of text. also I cant display Long Dynamically text in UILabel Fully, its show only selected Rows, it displays only selected line in Attribute inspector that much it will displays. how to fix this both problem. help me
-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section{
return [_data count];
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier = #"Cell";
SingleTableViewCell *cell = (SingleTableViewCell *)[_mytable dequeueReusableCellWithIdentifier:CellIdentifier];
if(cell == nil){
cell = [[SingleTableViewCell alloc]initWithStyle:UITableViewStylePlain reuseIdentifier:CellIdentifier];
}
cell.labelTitle.text=[_data objectAtIndex:indexPath.row];
cell.labelcount.text=[NSString stringWithFormat:#"%u", (arc4random() % 74)];
return cell;
}
This my Table delegate code. I saw my CGrect for calculate text size etc, but i will not work here.
I am using Xcode 6.1.1, and Objective-c .
You can use Autolayout and set the borders of the label to the cell then in your viewDidLoad method do this:
self.tableView.estimatedRowHeight = 44; // or your default size
self.tableView.rowHeight = UITableViewAutomaticDimension;

How to discover why heightForRowAtIndexPath is crashing

I am not a full-time iOS dev and I'm trying to return the cell at the current indexPath but this is crashing and I am not sure exactly why. I maintain the height dynamically on the cell. My cell is a custom UITableViewCell called MICell and I have a property called height which is dynamically calculated in the updateCell method.
#import "MICell.h"
-(CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
MICell *cell = (MICell *)[self tableView:tableView cellForRowAtIndexPath:indexPath];
// hardcoded to 200.0f but still crashing
NSLog(#"here is my height; %f",cell.height);
return 200.0f;
}
Edit 1
As a workaround, I am able to make an instance variable and just write the current cell height which is then accessed in heightForRowAtIndexPath, like the following. I do feel that this is potentially making assumptions that I'm not fully comfortable with:
#interface ListViewController (){
NSMutableArray *_data;
CGFloat _currentCellHeight;
}
...
-(MICell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"MICell";
MICell *cell = [tableView
dequeueReusableCellWithIdentifier:CellIdentifier
forIndexPath:indexPath];
// Configure the cell here ...
NSDictionary *tmp=[_data objectAtIndex:indexPath.row];
[cell updateCell:tmp];
_currentCellHeight=cell.height;
return cell;
}
-(CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
return _currentCellHeight;
}
Edit 2
Here's a reference to this exact technique. How to get the cell object in tableView:(UITableView *)tableView heightForRowAtIndexPath function?
Edit #3
The above code works fine - there was an issue with IB connections.
It's because you're causing an infinite cycle. You cannot call:
[self tableView:tableView cellForRowAtIndexPath:indexPath];
In height for row at index path.
[tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];
will cause issues when called from height for row at index path. You must call tableView dequeueReusableCellWithIdentifier: without the forIndexPath. You should probably create a configureWithCell:(YourCellClass *)cell method separate from these so you can just configure your cell after properly dequeueing/allocating it.
Also, you do not grab the height from the cell as you're doing above (unless you're assigning a height property with some weird forwarding stuff that breaks class containment... which you shouldn't do either). Use the following for dynamic cell heights via auto layout:
CGFloat cellHeight = [cell.contentView systemLayoutSizeFittingSize:UILayoutFittingCompressedSize].height;
Something like the following below should do the trick:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
MyCellClass *cell = [tableView dequeueReusableCellWithIdentifier:NSStringFromClass([MyCellClass class]) forIndexPath:indexPath];
[self configureMyCell:cell forIndexPath:indexPath];
return cell;
}
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
MyCellClass * cell = [tableView dequeueReusableCellWithIdentifier:NSStringFromClass([MyCellClass class])];
[self configureMyCell:cell forIndexPath:indexPath];
CGFloat cellHeight = [cell.contentView systemLayoutSizeFittingSize:UILayoutFittingCompressedSize].height;
return cellHeight;
}
In ios, the height of the cell is calculated in heightForRowAtIndexPath. What you are trying to do is to get height of the cell inside heightForRowAtIndexPath. It is definitely not the way to do it. To have dynamic height, calculate the height inside heightForRowAtIndexPath using the features/values you might need and return that height.
Bottom line is you cannot call cell.height inside heightForRowAtIndexPath.
Edit 1:
To help you deal with the dynamic heights in cell, please look at this tutorial. It might help you understand the issue : Dynamic Cell
Just go straight to the tableView delegates method to get an understanding of how to proceed.

Fitting UIImage inside a Table Cell

I have a table with a custom cell, which has only one UIImageView. I want each cell to have its own height based on an image height I will place in it. In my heightForRow method I have
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath {
FAppFormula *formula = self.formulas[indexPath.row];
UIImage *img = [formula getFormulaImageSmallSize];
if (img.size.height <= 100){
return 30;
}
return 75;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath: (NSIndexPath *)indexPath
{
static NSString *cellIDSmall = #"FormulaCellSmall";
FormulaCell *cell = (FormulaCell *)[tableView dequeueReusableCellWithIdentifier:cellIDSmall
forIndexPath:indexPath];
cell.formulaImage.image = formulaImg;
return cell;
}
The cells themselves do get proper heights, however images don't get scaled appropriately. In storyboard cell prototype I set UIImageView's mode to Aspect Fit, however looks like all images get scaled based on a default(?) row height, but not on the one which heightForRowAtIndexPath returns...
Any ideas on why it happens and how to fix it? How it looks now img

UIImage in TableViewCell pushes Cell Separator

I've added a UIImage to my table view cell. However, the UIImage is pushing the separator over to the right to make room for the UIImage. I'd like to find a way to have the separator include the UIImage and not be pushed over. Here is a picture of my table view cell.
Here is my cellForRowAtIndexPath method with code for the image:
-(UITableViewCell *)tableView:(UITableView *)tableView
cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"Cell";
UITableViewCell *cell =
[tableView dequeueReusableCellWithIdentifier:CellIdentifier
forIndexPath:indexPath];
Exercise *tempPlaceholder = [exercisesInTable objectAtIndex:indexPath.row];
NSString *exerciseDisplayName = tempPlaceholder.exerciseName;
exerciseDisplayName = [exerciseDisplayName capitalizedString];
exerciseDisplayName =
[exerciseDisplayName stringByReplacingOccurrencesOfString:#"_"
withString:#" "];
cell.textLabel.text = exerciseDisplayName;
cell.imageView.image = [UIImage imageNamed:#"quads.png"];
return cell;
}
If anyone could help me with this I'd really appreciate it. Thank you.
For anyone else who runs into this problem, using:
[self.tableView setSeparatorInset:UIEdgeInsetsZero];
will fill the gap between the UIImage and the table cell separator.
Try change the size of imageView frame
cell.imageView.frame = CGRectMake(0, 0, 10.0, 10.0);
Or change the height of cell
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath{
return 40.0;
}
The behaviour you are experiencing will only occur on iOS 7 where the separators have insets that by default change with image view size.
To remove this behaviour simply set the separator insets to zero. However the separatorInset property is available on UITableView from iOS 7.0
So you only have to remove the inset in iOS 7.
You can check whether the table view responds to setSeparatorInset: doing
if ([self.tableview respondsToSelector:#selector(setSeparatorInset:)])
{
[self.tableview setSeparatorInset:UIEdgeInsetsZero];
}

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