uitablviewcell dynamic height is not correct from systemLayoutSizeFittingSize

Question

I am using xib & auto layout to construct my custom cell,in my cell ,there is a multi line label. an in the tableview's heightForRowAtIndexPath, i will use

1 dequeueReusableCellWithIdentifier to get a cell

2 then call [cell.contentView systemLayoutSizeFittingSize:UILayoutFittingCompressedSize] to get the correct height .

But in debug , I found that when heightForRowAtIndexPath is called ,my cell's width is not the tableview's width, the cell's width is the same as the width of xib file (because in xcode6 ,you can set the xib size to any). so the height got from systemLayoutSizeFittingSize is not correct . how can I fix this problem to get the correct cell height

the size got from the systemLayoutSizeFittingSize: is not correct ,this size may have the width 340+ (while the device is iPhone5 whose width is 320),and the 340+ is accually the cell's xib file 's width

Finally, I got the solution ,thanks Ashish Gabani for help ,in fact ,the solution include 2 step: 1 reset the cell frame to your tableView size 2 call cell's layoutSubViews before you calling systemLayoutSizeFittingSize, and In your custom cell ,you need to rewrite the layoutSubViews method. Here is the code for fix this problem , I use the red square to mark them ,enjoy it

Answer 1

You Can Solve this Issue by Passing your Cell Height like as

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
// Determine which reuse identifier should be used for the cell at this index path,
// depending on the particular layout required (you may have just one, or may have many).
NSString *reuseIdentifier = ...;

// Dequeue a cell for the reuse identifier.
// Note that this method will init and return a new cell if there isn't one available in the reuse pool,
// so either way after this line of code you will have a cell with the correct constraints ready to go.
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:reuseIdentifier];

// Configure the cell with content for the given indexPath, for example:
// cell.textLabel.text = someTextForThisCell;
// ...

// Make sure the constraints have been set up for this cell, since it may have just been created from scratch.
// Use the following lines, assuming you are setting up constraints from within the cell's updateConstraints method:
[cell setNeedsUpdateConstraints];
[cell updateConstraintsIfNeeded];

// If you are using multi-line UILabels, don't forget that the preferredMaxLayoutWidth needs to be set correctly.
// Do it at this point if you are NOT doing it within the UITableViewCell subclass -[layoutSubviews] method.
// For example:
// cell.multiLineLabel.preferredMaxLayoutWidth = CGRectGetWidth(tableView.bounds);

return cell;
 }

 - (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
// Determine which reuse identifier should be used for the cell at this index path.
NSString *reuseIdentifier = ...;

// Use a dictionary of offscreen cells to get a cell for the reuse identifier, creating a cell and storing
// it in the dictionary if one hasn't already been added for the reuse identifier.
// WARNING: Don't call the table view's dequeueReusableCellWithIdentifier: method here because this will result
// in a memory leak as the cell is created but never returned from the tableView:cellForRowAtIndexPath: method!
UITableViewCell *cell = [self.offscreenCells objectForKey:reuseIdentifier];
if (!cell) {
    cell = [[YourTableViewCellClass alloc] init];
    [self.offscreenCells setObject:cell forKey:reuseIdentifier];
}

// Configure the cell with content for the given indexPath, for example:
// cell.textLabel.text = someTextForThisCell;
// ...

// Make sure the constraints have been set up for this cell, since it may have just been created from scratch.
// Use the following lines, assuming you are setting up constraints from within the cell's updateConstraints method:
[cell setNeedsUpdateConstraints];
[cell updateConstraintsIfNeeded];

// Set the width of the cell to match the width of the table view. This is important so that we'll get the
// correct cell height for different table view widths if the cell's height depends on its width (due to
// multi-line UILabels word wrapping, etc). We don't need to do this above in -[tableView:cellForRowAtIndexPath]
// because it happens automatically when the cell is used in the table view.
// Also note, the final width of the cell may not be the width of the table view in some cases, for example when a
// section index is displayed along the right side of the table view. You must account for the reduced cell width.
cell.bounds = CGRectMake(0.0f, 0.0f, CGRectGetWidth(tableView.bounds), CGRectGetHeight(cell.bounds));

// Do the layout pass on the cell, which will calculate the frames for all the views based on the constraints.
// (Note that you must set the preferredMaxLayoutWidth on multi-line UILabels inside the -[layoutSubviews] method
// of the UITableViewCell subclass, or do it manually at this point before the below 2 lines!)
[cell setNeedsLayout];
[cell layoutIfNeeded];

// Get the actual height required for the cell's contentView
CGFloat height = [cell.contentView systemLayoutSizeFittingSize:UILayoutFittingCompressedSize].height;

// Add an extra point to the height to account for the cell separator, which is added between the bottom
// of the cell's contentView and the bottom of the table view cell.
height += 1.0f;

return height;
 }

// NOTE: Set the table view's estimatedRowHeight property instead of implementing the below method, UNLESS
// you have extreme variability in your row heights and you notice the scroll indicator "jumping" as you scroll.
- (CGFloat)tableView:(UITableView *)tableView estimatedHeightForRowAtIndexPath:(NSIndexPath *)indexPath
{
// Do the minimal calculations required to be able to return an estimated row height that's
// within an order of magnitude of the actual height.
// For example:
if ([self isTallCellAtIndexPath:indexPath]) 
{
    return 350.0f;
} else {
    return 40.0f;
}
}

You can also Find the Solution From Here Link