I have no idea why, but when I touch a cell, image inside it kind of zooms and is partially of screen. Below you can see, the first row looks like it should and the second row was selected and now looks zoomed.
There is not much code, only ViewController and TableViewCell that both have minimum required code.
EDIT: Here's how I add cells, and there is no didSelectAtRow.
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("cell") as! TableViewCell
cell.myImage.image = UIImage(named: "uk.png")
return cell
}
EDIT2: Initially my imageView constrains where 0 to all margins, so that whole cell would be only image. When I made image quite small, none of zooming happens, so maybe I am doing something wrong with constrains?
Final Edit - Problem Solved
Not sure, how that zooming happened, but in my case trying different constrains solved the problem.
It is because your tableview is reuse its cell
First set the constraints of the cell.
and
also implement the
the code in cellForRowAtIndexPath with
if(cell == nil)
{
cell = [[UITableViewCell alloc] init];
}
also share your code for didSelectRowAtIndexPath
Related
In my tableview, every cell will be different and determined by a JSON response from server. And there will be infinite possibilities. So defining a prototype for each type of cell is not possible.
For example, one cell will have labels and buttons, another cell have images and buttons in different orders.
How to achieve this dynamic structure in tableview cells?
Currently what I am doing is: adding views as subview in cellForRowAtIndexPath but scrolling is very laggy this way.
How to achieve this without affecting performance this much
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("cell") as! MyCell
for myview in data[indexPath.row].myviews{
cell.addSubview(myview)
}
return cell
}
If you're using a table view then your content is going to scroll vertically, right?
There is a physical limit to the amount of UI that you can put horizontally. Limited by the screen size.
So I'm guessing your UI parts are being laid out vertically in the cell?
So instead of laying out a button, label, image, another button, and a text field vertically in a cell...
Create a cell type called ButtonCell, LabelCell, ImageCell, MultiLineLabelCell, TextFieldCell, etc...
So now, instead of creating one cell with all these elements added. You instead create multiple cells each containing one type of UI. Now you can dequeue your cells in any particular order (driven by your JSON) and won't lose the performance.
The only solution I see is to have empty cell and add/remove subviews as needed. But you should add new subviews to a cell only if you did not add them before.
For example:
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("cell") as! MyCell
if cell.contentView.viewWithTag(1) == nil {
let label = UILabel()
label.tag = 1
cell.contentView.addSubview(label)
}
let label = cell.contentView.viewWithTag(1)
// label config there
return cell
}
Also don't forget to add subviews to cell's contentView not to cell itself.
I have a UITableViewController containing my own cells that I dequeue in cellForRowAtIndexPath.
After dequeuing, I configure the cell and reload, asynchronously, the image for that cell.
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
if let cell = tableView.dequeueReusableCellWithIdentifier("PeopleCell", forIndexPath: indexPath) as? PeopleListViewCell {
cell.configureCell(headImageUrl)
}
}
In my PeopleListView class,
func configureCell(img:NSURL) {
if headImageView == nil { // to avoid allocation memory if not used
headImageView = UIImageView()
addSubView(headImageView)
}
headImageView.sd_cancelCurrentImageLoad()
headImageView.sd_setImageWithURL(headImageUrl)
}
It works fine at the first loading and also while scrolling.
But when I push another viewController after
didSelectRowAtIndexPath
and come back to the list after the
dismissViewController()
I end up with a weird effect on my UIImageView , it's kind of a stacked or ghost image effect..
I'm having a hard time to figure out where is even triggered as when I m coming back from the viewController, cellForRowAtIndexPath is not called.
This actually has nothing to do with asynchronous image loading.
The images I had was displayed within circles, with a cornerRadius.
Somehow, it was displayed without any problem at first load...
The issue here is I simply forgot the
headImageView.layer.maskToBounds = true
The result I got before setting maskToBounds to true was that I had the feeling that multiple images were located within the headImageView (UIImageView). If you ever have some artefacts like that, I hope this question/answer will help you.
I am creating a custom cell and I add subviews to it for text mostly. At first the subviews were not getting deleted when the cell was reused, so the text would overwrite and blot really bad. Then I added this for loop to the function and it solved my problem except that it also completely removes my imageView and it never gets re-added, so my whole tableview is missing the image that is supposed to be associated with each cell.
The if statement didn't work, but I didn't explicitly use cell.addSubView() as i did for the cell labels, so I am wondering if that has something to do with it. I have googled and found that most people are saying this worked for them, but I just cannot seem to figure it out.
Why does this remove my images, why won't they come pack like the other subviews, and how can I fix this?
I have the following code:
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("cell") as! UITableViewCell
for subView in cell.subviews {
if subView as? NSObject != cell.imageView {
subView.removeFromSuperview()
}
}
var statusImage = UIImage(named:imageConfigration(indexPath.row))!
cell.imageView?.image = statusImage
// ...
}
Give your imageView a tag in storyboard or xib or programmatically what you are using. Now in the for loop of subviews check if tag of the subview is equal to tag to imageview dont remove it.
Also another option to solve this if it fits your requirement is to hide all the elements added to cell except imageview. That will be much faster then looping in subviews and removing it you never know what all subview are attached to cell other then you added by iOS but thats if it fits your req. Let me know in case of any concern
This how you can do this
cell.textLabel.hidden = YES;
I want to have a button in my custom cell which is right aligned. Doing it with auto layout and setting a horizontal space from the right and centering it vertical does not show the Button in my cell because it is too far at the right.
In the picture you can see my cell. But it is not shown like this in the actual app.
Edit: I tried your answer but this does not seem to work. My TableView looks kind of strange in the Emulator:
Is it possible that there is a problem in my controller?
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("eventCell", forIndexPath: indexPath) as EventTableViewCell
let event = items[indexPath.row]
cell.contentView.autoresizingMask = UIViewAutoresizing.FlexibleHeight | UIViewAutoresizing.FlexibleWidth
return cell
}
Do the following for that Button:
Set Width and Height constraints
set Vertical center constraints to the cell view
Set horizontal/trailing(may be 10px) space to the right side of the cell view
Sry I am dumb.
Everything was fine with my Cell layout. I was so focused on the cell that I forgot to add constraints to the TableView. Adding these constraints fixed the problem.
I have a UITableView with the subtitles hidden but set up where when someone selects a cell it shows that cell's subtitle. This works fine except that after tapping any cell to reveal its subtitle if you scroll down you will find that every 12 cells have their subtitle unhidden (as well as the one it was supposed to reveal). Here is the code I'm using in didSelectRowAtIndexPath:
override func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
for cell in tableView.visibleCells() {
cell.detailTextLabel??.hidden = true
}
var cell = tableView.cellForRowAtIndexPath(indexPath)
cell?.detailTextLabel?.hidden = false
}
I'm sure this is related to ".visibleCells()" since every 12 cells is about the height of my visible table on my iPhone 6 Plus. When I run it on a 4s in the simulator it's about every 8 cells. But I'm not sure how else to do it besides 'visibleCells'? But it's strange because it's the whole table - all the way down, every 12 cells is showing its subtitle...
thanks for any help
UITableView reuses its cells. So the cell for row a row you clicked on (unhidden the subtitle) may be used for row another row.
The solution is to define prepareForReuse() method in the UITableViewCell subclass (or make the subclass if you do not have one) and hide the subtitle again there.
Add that dataSource's method to your controller. Should work fine.
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) {
var identifier = "cellIdentifier"
var cell = tableView. dequeueReusableCellWithIdentifier(identifier, forIndexPath: indexPath)
cell.detailTextLabel?.hidden = true
return cell
}