I have subclassed a UITableViewCell and within this class I want to get it's height. How can I achieve this?
I have tried:
self.frame.size.height
but not sure if it is giving me the correct height value.
You can use either self.bounds.size.height or self.contentView.frame.size.height, depending on which you actually need. They often differ by 1.0f which is the thickness of the table view cell separator.
Keep in mind that you can rely on those values mainly in -layoutSubviews, in other words after the table view sets the cell's frame.
Related
Setup: I have a scrollview with a label, uiimage, and a tableview (grouped) nested within. The label, uiimage, and tableveiw are populated by a webservice. The last section in the grouped table view contains text that will never be the same and could be as long as 5 characters to 250+. Also, this view is pushed from a basic tableview (so it has a navigation bar. If that matters at all).
Expected: The tableview should extend in height depending on the length of the content received from the web service. Then set the scrollview height to accommodate the height of the tableview
Problem: I'm not quite sure how to approach the issue. I really only know how to change the height to fixed values, which will not work properly in many scenarios.
The width and height of the cell are ignored; the cell cell is re-sized according to the value you return from -tableView:heightForRowAtIndexPath: or (failing that) tableView.rowHeight. It might appear as if the cell is big enough if the label in the cell is sized to be big enough, because the label is allowed to be bigger than (and render outside) the cell.
One way is to override -tableView:heightForRowAtIndexPath: to return the correct height. This isn't really the intended use of UITableView (it's primarily designed for lots of rows of a single height, dynamically generated from a list of content).
Another way is to set tableView.tableFooterView = myCustomFooter instead. This is probably the easiest way. Size it correctly before performing the assignment (the height matters; the table view will set the width for you anyway). Also make sure that the autoresizing flags are not set, or the size will appear to randomly change when the table view changes size (e.g. on autorotation).
I'd just focus on the variable height element, figure out the height that fits the text there. To figure out the height that a string will take when rendered use a snippet like this:
CGFloat MY_TABLECELL_WIDTH = 320;
CGFloat MY_MAX_HEIGHT = 10000;
UIFont *MY_FONT = nil; // load the correct font here.
CGSize maxSize = CGSizeMake(MY_TABLECELL_WIDTH,MY_MAX_HEIGHT);
CGSize textSize = [serverString sizeWithFont:MY_FONT
constrainedToSize:maxSize
lineBreakMode:UILineBreakModeWordWrap];
I am basically trying to find the correct way to design a UITableViewCell that has two UITextViews and three UILabels inside it. The two UITextViews have dynamic content and their size cannot be determined until runtime.
I have tried various methods of recalculating the height of my UITextViews based on the content that is loaded in them at runtime, and though very laborious and inane, I have gotten that to work, but they then bleed over the UILabels positioned in the xib below them.
Do I really have to recalculate the y coordinates of every UILabel after calculating the new size of the UITextViews? Is there a way to simply have the elements in the xib 'push' the elements below them down based on their new size?
What is the correct approach to configuring a UITableViewCell with multiple dynamic text views so that my entire application is not comprised of code to calculate heights and coordinates?
Or is the answer that I should not be putting more than one dynamic UITextView in the same UITableViewCell ?
I have used something like this for a cell to calculate its height in
tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
function
CGSize labelSize = [self.comments sizeWithFont:[UIFont fontWithName:#"Verdana" size:17.0]
constrainedToSize:CGSizeMake(280.0f, MAXFLOAT)
lineBreakMode:UILineBreakModeWordWrap];
return labelSize.height + 20;
+20 is for padding.
and also if you are having every cell like the one you mention above, than you can create a class of UITableViewCell with following UIView elements inside it.
iOS doesn't seem to have any sort of flow layout engine -- at least none that I can think of.
If, however, your labels are located at the bottom of your UITableViewCell, you might be able to get away with setting the UILabel's autoresizingMask mask property to UIViewAutoresizingFlexibleBottomMargin so that the UILabels will anchor itself at the bottom. This is assuming that you already adjusted the size of the UITableViewCell to fit the entire controls. Otherwise, I think the best way to handle this is to recalculate the y coordinates of the labels.
I found it useful to add this sort of behavior as a category on UIView so a view can resize one of its subviews to fit some arbitrary text, and optionally resize the parent view to fit the newly enlarged subview as needed.
http://blog.carbonfive.com/2009/07/10/resizing-uilabel-to-fit-text/
I have a UITableViewCell with two subviews, a UILabel on the left, and a random input control on the right. The random input control on the right can vary in size, as can the length of the text, but since I can set the word wrap of the text on the left, I need to be able to adjust the size of the UILabel based on the width of the random input control. To complicate matters, the app needs to work in both portrait and landscape modes, which give the table cells different widths.
This wouldn't be difficult if I could read the width of the table cells and set the widths of its subviews appropriately, but at creation time the width of the cell is 0.
Any ideas?
Nothing easier than that: every UITableViewCell is also a UIView, which has a method designed for just that: layoutSubviews, which is called whenever the view (here: cell) needs a re-layout. This is where you lay out the content.
Alright so I have a situation here that is making me go crazy. I am loading a UITableView with a custom UITableViewCell. Now this cell has couple of UILabel's in it.
so the order is:
Label1
Label2
Label3
Label4
Now Label2 has a fixed height. Label1, Label3 and Label4 will need to change their height according to the size of string. I am using the recommended way to calculate the height for each label using: - sizeWithFont:c constrainedToSize: lineBreakMode:UILineBreakModeWordWrap
But the label's are overlapping each other. Not sure how to position these labels?
Or is there a better way to do this?
Thanks
Position the first label, get its size, and then position each subsequent label by the previous label's frame.
For convenience, you might put this code into a separate method, calling it once to generate that cell's height for use in the -tableView:heightForRowAtIndexPath: delegate method, as well as have those labels set up for the -tableView:cellForRowAtIndexPath: delegate method.
I have a custom table cell which contains a number of UILabels. At runtime, I am adjusting the height of the labels to fit their contents using sizeWithFont:constrainedToSize:lineBreakMode: and repositioning them accordingly. The last label in the cell contains a large amount of text, causing it to wrap, and I'm having a very odd problem. Although the sizeWithFont call returns the correct size, and I'm setting the UILabel's frame to that height, it draws a couple of lines short. This screenshot illustrates what I'm talking about:
In this example, the height of the full block of text should be 90 (as checked in Interface Builder), and that's what returns from sizeWithFont. It's also the height that the UILabel's frame is set to, which I have verified by logging and also by stopping execution and inspecting the value. However, as you can see, it's clearly not drawing the full 90 pixels high, although it's correctly allocating the space for it (the thin black line above 'Edited' is the table cell border). I'm completely perplexed. If anyone can offer some insight as to why it's behaving this way, I would be very grateful.
At last, a solution!
Turns out that the cell does layout twice -- once during heightForRowAtIndexPath, which is where I tweak all the heights of the subviews and the cell, and later during some untraceable transaction originating in __CFRunLoopDoObservers. How did I trace this? I added a layoutSubviews override to my custom table view cell class so I could breakpoint it.
During the second pass, the last UILabel subview was getting set to a shorter height than I set it to, probably in accordance with some arcane autoresizing rules. (Yes, I tried tweaking all of those settings first, with no success.) As it turns out, merely doing nothing in layoutSubviews disabled this framework behavior, allowing me to completely control how my views draw.
With iOS 8 it doesn't work anymore like this. Implementing layoutSubviews alone doesn't do the trick, because the layout of subviews have already changed when the method is called.
I have found 2 solutions:
adding NSLayoutConstraint to layout the subviews programmatically
implementing subview's layoutSubviews and change the frame
An example für solution 2:
- (void)layoutSubviews
{
[super layoutSubviews];
CGRect frame = self.frame;
frame.size.height = 39.f;
self.frame = frame;
}
I've fought with similar problems. It was to do with other properties being set in previous incarnations of the cell. To find it / prove it I changed the reuseidentifer for the offending cell to make sure it was a unique cell.