How to change Tableview's custom cell width dynamically ? - ios

I have a table view and its every cell`s width say 1024px , so my requirement is after clicking a cell tableview's width will change logically. And my table view is bit complex.
Every cell contains a custom view which is defined in another class. Please help me..

I do not believe there is a way to modify a single cell's width without changing the width of the table view, only height using tableView:heightForRowAtIndexPath:.
Therefore, you might want to change the width of the custom view inside your cell.
First, to get the cell in question, call cellForRowAtIndexPath: on your table view wherever you need (if you want to change the width on tap, that would probably be in your tableView:didSelectRowAtIndexPath:).
To access your custom view, you may give your custom view a tag number inside of the UITableViewCell by setting the custom view's tag property when creating the cell or in the storyboard. Then, call viewWithTag: on the UITableViewCell instance to get the custom view, and modify the width of its frame property.
Another, perhaps more suitable option would be to use a custom UITableViewCell class for your table view cells. That would mean subclassing UITableViewCell and creating a property for your custom view, which would allow you to access the custom subview through the getter and then change its frame property.
If you need the width of the custom view's container to change (which is currently your cell), simply embed the custom view inside a UIView and modify the UIView's width rather than the UITableViewCell's instance in the same manner described above.

Related

Replace a subview in UICollectionView, instead of changing subview properties

I'm trying to implement a subclass of UICollectionViewCell.
I'm getting an array of custom views, let's call it views passed from one object to another, also with an array called views. They are of type CustomView.
The UICollectionViewCell subclass has one property called view of type CustomView.
In CellForItemAt..., I'm trying to set the cell's view property from an array of CustomViews like this:
let customView = array[indexPath.row]
cell.view = customView
However, when I do this, the cells don't show properly; they're empty, and just grey shapes on the screen.
But, when I explicitly set the properties of the cell's CustomView subview, it shows how I'd like it to.
Is there a way to do a layout pass on the cell? Or do you have to just explicitly set properties in UICollectionViewCells instead of just passing in a pre-configured view?
The code is proprietary, so I have to be cryptic, but please let me know if I can clarify
Edit: Please see the comments in the accepted answer for further explanation
You should be adding constraints, or else you are getting the default auto resizing mask constraints. Call cell.setNeedsLayout() to force auto layout to recalculate before the next draw after you assing the voew.

Unable to resize an UITableViewCell containing an UIView

I have a custom table view cell. I have a UIView in the tableview cell that is shown only when the table is expanded. I toggle the height for table view cell each time on tap to show the UIView. I also need to detect clicks on some of the components of UIView.
->tablecell1
-->UIView1 height h1
->tablecell2
-->UIView2 height h2
The cell height of the cell should vary according to the size of UIView. Currently I am calling
tableView:heightForRowAtIndexPath: for varying the height on cell click. However this doesn't work if the UIViews are of variable heights and the bigger view gets clipped.
Is there a better way of solving it?
Ok so real quick tableView:heightForRowAtIndexPath: shall not be called by your controller.
The biggest problem I always run into when dynamically sizing cells is that that heightForRowAtIndexPath is called very early on in the table layout process, so essentially the height of each cell must be know prior to asking the tableview to layout. Anyway I am going to assume that you are using a custom table view cell and have placed a UIView inside there... If you haven't, do.
First: Throw a class function into the CustomTableViewCell called heightNeededForTableViewCellWithView:(UIView *)view and determine the height you would want, handle the condition where view is nil and what the default size shall be.
Second: Call this class function when tableView:heightForRowAtIndexPath: is called and since you own the datasource in your controller you can dynamically return the heightNeededForTableViewCellWithView:viewAtRow based off the view you would want to show for that row!
Third: When a user taps a cell, remember which index they tapped and call [tableView reloadData] which will call tableView:heightForRowAtIndexPath:

Custom Prototype Cell designed in Storyboard with Custom View Controller

The main problem is that it does not respect the design done in the storyboard. The coordinates of the image and the labels are as a basic cell. Note that such attributes are observed as the alignment of the label.
The button that has been added, is below the label.
I've definitely seen this issue before and I believe it is because imageView and textLabel are properties of UITableViewCell and the default implementation of layoutSubviews is overriding your storyboard's layout with UITableViewCell's defaults.
Try overriding layoutSubviews, or provide your own image and label properties (named differently from UITableViewCell's, ie: myImageView and myTextLabel).

Grouped TableView cell width

In iOS6, I cannot seem to get the width of the cell in cellForRowAtIndexPath for the grouped table style. Logging either the frame or the bounds for either the cell or its contentview returns 320 - even on iPad. I need to determine the cell width programmatically for any device as I need to calculate text sizes. Any advice in getting the correct cell width for a grouped tableview in cellForRowAtIndexpath would be appreciated please
The method you're using is the wrong place to calculate any kind of view-related constraints. The -tableView:cellForRowAtIndexPath: method is part of the table view's data source, not its delegate. You cannot rely on the frame or anything else here to be meaningful, it's meant as the place to configure the cell's /data/.
If you need to make calculations to view frames and such, and you're not using a custom subclass of UITableViewCell (i.e., you're just adding views to a default instance of UITableViewCell or configuring stock views), you would set up any frame-related / view specific attributes in the /delegate/ callback -tableView:willDisplayCell:forRowAtIndexPath: method. This is the place to configure any of the visible/view-related properties of your cell, and you will now have accurate layout information for the cell (its bounds will be correct, any layout/configuration of internal views will be complete, etc.).
If you have a custom subclass already, you can either do your view related property configuration in the delegate callback above, or you can do it in UIView's -layoutSubviews method, depending on your exact needs. For more information, see the documentation for -tableView:willDisplayCell:forRowAtIndexPath:.

Getting real width of UITableViewCell's contentView before it displays

I have a grouped table view with custom cells (created programmatically by subclassing, not with IB). To properly position custom cell's subviews (such as labels and text fields), I need to know the current width of the cell's contentView just before the cell displays (taking into account that real cell width in a table view can change (according to screen orientation, modal presentation style, etc.)).
if I override in custom cell class the layoutSubviews method, it works perfectly, but it can be called frequently, thus I have to reposition my subviews every time when it's called, even when there's no need to do that.
Please, recommend me more elegant solution.
The recommended way of doing this is by setting the autoresizingMask of the table cell. If you need to have more control over the layout, you can store the last used view width in a member variable, and only layout the subviews if this differs from the current view width.

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