UITableView cell contents not displayed properly - ios

Question

I use auto layout and want to display UITableView with custom cell that has a UITextView with variable content.
Cells are displayed as shown below. For chat message, when cell is first displayed only 2-3 characters are displayed in a single line and next characters are forced to go to next line. But when I scroll tableView so that these cells are not visible and scroll back to make them visible (I do this so that when they are visible again cellForRowAtIndexPath: method is called again to render the cell), they render the cell properly as shown in second image.
Code :
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
return [chatData count];
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
RS_User *user = [[RS_User alloc]init];
chatCell *cell = (chatCell *)[tableView dequeueReusableCellWithIdentifier:CHAT_CELL_IDENTIFIER];
NSUInteger row = indexPath.row;
cell.chatCellBackground.image = nil;
NSString *chatText = [[chatData objectAtIndex:row] objectForKey:TEXT]; // get text string(message) from array
cell.textLabel.lineBreakMode = NSLineBreakByWordWrapping;
UIFont *font = [UIFont systemFontOfSize:FONT_SIZE];
cell.textString.font = [UIFont fontWithName:FONT_NAME size:FONT_SIZE]; // set text font
cell.textString.text = chatText;
// set text
CGSize size = [cell.textString.text sizeWithFont:cell.textString.font constrainedToSize:CGSizeMake(SET_WIDTH, MAXFLOAT) lineBreakMode:NSLineBreakByCharWrapping];
cell.textString.frame = ...;
[cell.textString sizeToFit];
NSDate *theDate = [[chatData objectAtIndex:row] objectForKey:DATE];
NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
[formatter setDateFormat:DATE_FORMAT];
NSString *timeString = [formatter stringFromDate:theDate];
cell.timeLabel.text = timeString; // set timeLabel to display date and time
cell.timeLabel.font = [UIFont fontWithName:FONT_NAME size:SMALL_FONT_SIZE];
cell.userLabel.text = #"Name";//[[chatData objectAtIndex:row] objectForKey:NAME]; // set userLabel to display userName
CGSize size1 = [cell.userLabel.text sizeWithFont:font constrainedToSize:CGSizeMake(SET_WIDTH, MAXFLOAT) lineBreakMode:NSLineBreakByCharWrapping];
// check cell contains sender name or receiver name
if (thisCellIsForSender)
{
// Set bubble for sender
cell.chatCellBackground.image = [[UIImage imageNamed:#"bubbleMine.png"] stretchableImageWithLeftCapWidth:STRETCHED_WIDTH topCapHeight:STRETCHED_HEIGHT];
cell.chatCellBackground.frame = ...;
}
else
{
// set bubble for receiver
cell.chatCellBackground.image = [[UIImage imageNamed:#"bubbleSomeone.png"] stretchableImageWithLeftCapWidth:STRETCHED_WIDTH topCapHeight:STRETCHED_HEIGHT];
cell.chatCellBackground.frame = ...;
}
[cell setNeedsLayout];
[cell layoutIfNeeded];
return cell;
}
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
RS_User *user = [[RS_User alloc]init];
chatCell *cell = (chatCell *)[tableView dequeueReusableCellWithIdentifier:CHAT_CELL_IDENTIFIER];
NSUInteger row = indexPath.row;
cell.chatCellBackground.image = nil;
NSString *chatText = [[chatData objectAtIndex:row] objectForKey:TEXT]; // get text string(message) from array
cell.textLabel.lineBreakMode = NSLineBreakByWordWrapping;
UIFont *font = [UIFont systemFontOfSize:FONT_SIZE];
cell.textString.font = [UIFont fontWithName:FONT_NAME size:FONT_SIZE]; // set text font
cell.textString.text = chatText;
// set text
CGSize size = [cell.textString.text sizeWithFont:cell.textString.font constrainedToSize:CGSizeMake(SET_WIDTH, MAXFLOAT) lineBreakMode:NSLineBreakByCharWrapping];
cell.textString.frame = ...;
[cell.textString sizeToFit];
NSDate *theDate = [[chatData objectAtIndex:row] objectForKey:DATE];
NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
[formatter setDateFormat:DATE_FORMAT];
NSString *timeString = [formatter stringFromDate:theDate];
cell.timeLabel.text = timeString; // set timeLabel to display date and time
cell.timeLabel.font = [UIFont fontWithName:FONT_NAME size:SMALL_FONT_SIZE];
cell.userLabel.text = [[chatData objectAtIndex:row] objectForKey:NAME]; // set userLabel to display userName
[cell setNeedsUpdateConstraints];
[cell updateConstraintsIfNeeded];
CGSize size1 = [cell.userLabel.text sizeWithFont:font constrainedToSize:CGSizeMake(SET_WIDTH, MAXFLOAT) lineBreakMode:NSLineBreakByCharWrapping];
// check cell contains sender name or receiver name
if (thisCellIsForSender)
{
// Set bubble for sender
cell.chatCellBackground.image = [[UIImage imageNamed:#"bubbleMine.png"] stretchableImageWithLeftCapWidth:STRETCHED_WIDTH topCapHeight:STRETCHED_HEIGHT];
cell.chatCellBackground.frame = ...;
}
else
{
// set bubble for receiver
cell.chatCellBackground.image = [[UIImage imageNamed:#"bubbleSomeone.png"] stretchableImageWithLeftCapWidth:STRETCHED_WIDTH topCapHeight:STRETCHED_HEIGHT];
cell.chatCellBackground.frame = ...;
}
cell.bounds = CGRectMake(0.0f, 0.0f, CGRectGetWidth(tableView.bounds), CGRectGetHeight(cell.bounds));
[cell setNeedsLayout];
[cell layoutIfNeeded];
return cell.bounds.size.height;
}
UPDATE : I could solve some of the issues from coverback's answer. Still cell is not laid out correctly. I am adding photos for constraints of each UI object in cell.
User name :
Time stamp :
Chat message :
Bubble image :
Cell Layout :
Cell height in cellForRowAtIndexPath: is always 100 even though I return different value from heightForRowAtIndexPath: method. Cell height in storyboard is 100.
Chat message in third cell is clipped from bottom.
Time stamps and chat message labels are some time not aligned properly to each other even though both have constraint vertical spacing from username label.
Username label in third cell is vanished.
Do you see anything wrong in constraints? You can ask me if analyzing constraints is difficult.

Answer 1

Combining the answers by thandasoru and coverback solved my issue. Below is the code I use.
I added below method in custom UITableViewCell's class.
- (void)layoutSubviews
{
[super layoutSubviews];
CGFloat maxTextWidth = [UIScreen mainScreen].bounds.size.width * 0.40;
self.userLabel.preferredMaxLayoutWidth = maxTextWidth;
self.chatMessage.preferredMaxLayoutWidth = maxTextWidth;
self.timeLabel.preferredMaxLayoutWidth = self.timeLabel.frame.size.width;
[super layoutSubviews];
}
UITableView datasource methods :
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
CustomCell * cell = (CustomCell *)[tableView dequeueReusableCellWithIdentifier:#"customCellId"];
// Set all label's text and image to ImageView
...
// Update layout
[cell setNeedsLayout];
[cell layoutIfNeeded];
}
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
customCell * cell = (customCell *)[self tableView:tableView cellForRowAtIndexPath:indexPath];
NSString * userName = cell.userLabel.text;
NSString * chatText = cell.chatMessage.text;
// Get bounding rect of userName label
CGRect userNameFrame = [userName boundingRectWithSize:CGSizeMake(maxLabelWidth, MAXFLOAT) options:NSStringDrawingUsesLineFragmentOrigin attributes:#{NSFontAttributeName:cell.userLabel.font} context:nil];
// Get bounding rect of chatMessage label
CGRect chatTextFrame = [chatText boundingRectWithSize:CGSizeMake(maxLabelWidth, MAXFLOAT) options:NSStringDrawingUsesLineFragmentOrigin attributes:#{NSFontAttributeName:cell.chatMessage.font} context:nil];
// Calculate cell height from its contents
height = userNameFrame.size.height + chatTextFrame.size.height + PADDING_ABOVE_TOP_LABEL + DISTANCE_BETWEEN_TWO_LABELS + PADDING_BELOW_BOTTOM_LABEL;
return height;

Answer 2

You can determine the cell height dynamically so that the text appears on one line. I've given CGSize(320,568) as bounds. But you can change the size as you see fit
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
NSString *chatText = [[chatData objectAtIndex:row] objectForKey:TEXT];
CGRect frame = [chatText boundingRectWithSize:CGSizeMake(320,568) options:NSStringDrawingUsesLineFragmentOrigin attributes:#{NSFontAttributeName:[UIFont systemFontOfSize:18.0f]} context:nil];
return frame.height; //returns cell's height after calculating the area that text needs
}

Answer 3

You are setting the frame of the text and calling sizeToFit:
CGSize size = [cell.textString.text sizeWithFont:cell.textString.font constrainedToSize:CGSizeMake(SET_WIDTH, MAXFLOAT) lineBreakMode:NSLineBreakByCharWrapping];
cell.textString.frame = ...;
[cell.textString sizeToFit];
This will not be working with autolayout. You need to remove setting the frame and sizeToFit completely, same goes for all other frame being set directly. If things don't work after that, it would mean some constraints are not correct. But mixing approaches always breaks layout.
For UILabels, make sure to also set preferredMaxLayoutWidth to label's width, otherwise text may not wrap correctly:
- (void)layoutSubviews
{
[super layoutSubviews];
self.label.preferredMaxLayoutWidth = self.label.frame.size.width;
[super layoutSubviews];
}
Also, your height calculating method should not just do same thing as cellForRowAtIndexPath:, if you want to use the same code, just call that other method to get a cell.