I have a UITableViewController and when I click on it, it will show a DetailViewUIController.
I want to add a functionality which when I am in DetailViewUIController and I swipe to right, it will show the DetailViewUIController of next item and when left, it will show the previous item.
I find a link which kind of do that in swift. But it only has 3 static subviewcontroller.
https://medium.com/swift-programming/ios-swipe-view-with-swift-44fa83a2e078
The number of entries in my TableView can be pretty long, how can I do the same thing dynamically, i.e. without having static number of subviewcontroller created and add as 'addChildViewController'?
Update:
Thanks again #rdelmar for your help.
I am having trouble getting the ' set the contentOffset of the collection view to (collection view width) * selectedRow' to work.
In my prepareForSegue function, I have added:
x = Float(indexPath.row) * 375.0
var point = CGPointMake(CGFloat(x), 0)
println ("***x=")
println (x)
detailController.collectionView?.setContentOffset(point , animated: false)
where detailController is UICollectionViewController.
and in the
override func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCellWithReuseIdentifier(reuseIdentifier, forIndexPath: indexPath) as DetailViewCell
// Configure the cell
println("DetailViewController in cellForItemAtIndexPath()")
println(indexPath.row)
cell.myitem = allItems[indexPath.row]
return cell
}
And I always see cellForItemAtIndexPath trying to get 0th element of the allItems (that is the whole collections of all my objects.
So setContentOffset() does not change what I am displaying in the Detail View regardless which item I click in my TableView to launch the Detail View.
Any idea to solve this?
Thank you.
There are a lot of different ways you could do this. One way would be to make your detail view controller's view be a collection view (with paging enabled), whose cells are the same size as the screen. You would need to pass in the array that you use to populate your table so the collection view could populate its cells. This would be quite efficient, since the collection view would only ever need to instantiate two cells.
Related
I've got a UICollectionView in a modal view controller in my app. When the modal view is brought up, one of the collection's cells is set as selected based on certain data I pass into the modal view from my home view.
I need to programmatically scroll the selected collection cell into view once the modal view with the collection appears... but using scrollToItem(at:at:animated:) while the collection view is being populated (in cellForItemAt) doesn't seem to work.
So while I could easily just use the indexPath available to me in cellForItemAt to scroll to the selected cell while populating the collection, since that isn't possible, I can't figure out how to scroll to the currently selected collection cell after the collection is fully populated and presented.
I can't even use a heavy-handed approach like looping through all collection cells and checking which is selected manually, since it doesn't appear possible to loop through cells that aren't currently visible.
Help?
Add a variable on Top.
private var didLayoutFlag: Bool = false
Just pass the index number (indexNO) in viewDidLayoutSubviews method. I am using horizontal scrolling.
override func viewDidLayoutSubviews() {
super.viewDidLayoutSubviews()
if self.colllecitonView != nil {
if !self.didLayoutFlag {
self.colllecitonView.scrollToItem(at:IndexPath(item: indexNO, section:0), at:.right, animated: false)
self.didLayoutFlag = true
}
}
}
I have checked, tried many solutions on stackoverflow and from many website I searched.
My problem: I have a collection view inside table view cell. My data must be loaded 1 time in table view ( viewdidload).
When I pass data to collection view inside table cells, it's not appear because I need to reload collection view again.
So I do: Data -> inside cellforrow of table view -> Pass to collection view -> cell.collectionView.reloadData()
This cause a problem about scroll performance: collectionView.reloadData() call over and over again when I scroll ( this right because of resuable cells architecture of table view.
Here my code in cellforrow of tableView:
let cell = tableView.dequeueReusableCell(withIdentifier: SubCategoryCellID) as! SubCategoryCell
if isFetched {
cell.shimmeringView.isShimmering = false
cell.shimmeringImageView.isHidden = true
cell.shimmeringView.isHidden = true
cell.listLocation = nestedSubLocation[indexPath.item]
cell.collectionView.reloadData()
}else {
return cell
}
Solutions I tried:
+ Create static cells and get cells to display in cellForRow (it's totally fix scroll performance but I think it not good for memory management and it's not working if parent is collection view).
+ Reload data when scroll stop: it's still need to reloadData in loading first time and wrong data if I dont reload again.
To fix that, anyone have an clever approach to fix scroll performance ?
Put this code after cell.collectionView.reloadData()
cell.collectionView.scrollRectToVisible(CGRect.zero, animated: false)
I've got a collection view with multiple cells created programically. I want to update a variable to a different value when the user taps a specific cell. So eg: Cell 1 is tapped -> var test = "cell1" , cell2 is tapped var test = "cell2". Usually I'd just create an IBAction by dragging from the storyboard but I'm not sure how to do it in this case.
I'm using Swift 3.1
To add interactivity to UITableViews, UICollectionViews, and other kinds of views which display collections of data, you can't use Storyboard actions, as the content is generated dynamically during runtime, and the Storyboard can only work for static content.
Instead, what you need to do is set your UICollectionView's delegate property to an object that implements the UICollectionViewDelegate protocol. One of the methods defined as part of the protocol is the collectionView(_:didSelectItemAt:) method. This method will get called whenever the user selects (taps) a collection view cell with the IndexPath to that cell as an argument. You can update your variable in that method. Just remember to deselect the cell after handling the tap by using the deselectItem(at:) method on your UICollectionView.
There are UICollectionView delegate that you need to implement. It goes like this
did select item at index path will give index path of the cell that was selected. Using indexpath or any other property of the data source array you are using, you can modify the variable value.
override func collectionView(collectionView: UICollectionView, didSelectItemAtIndexPath indexPath: NSIndexPath) {
if let cell = collectionView.cellForItemAtIndexPath(indexPath) {
//check your condition and modify the variable value depending on index path or any other property you are referring to.
}
}
I am trying to use a UIcollectionView in my SpriteKit game to display the level select scene. The collection view has 6 sections (start, world 1-5) with 8 cells in each (level 1-8). They are custom cells with a simple UILabel for now.
I can use the did select item for index path to load my levels, it's all good. However my problem is the following
The first section in the collection view is the start screen so I don't want the collection view to show the 8 cells in that section. That section is supposed o only showing a background image and a tap to start lable. So what I tried in cellForIndexPath is to
1) hide cells in that section but that causes text label issues with the cells in the other sections
2) hide the text labels and make the cells color transparent, same problem as 1
So basically what could I do to solve this issue?
I could put the start section into a different SKScene but I prefer if it's all in the collection view.
Another option I was thinking is to make each section have only 1 cell, the size of screen, and add 8 UIButtons to each section except the start section.
I also need some of those cells/buttons to be disabled until the previous level is unlocked. I am not sure what a better approach is, 8 cells as buttons or 8 UIButtons in 1 cell.
I am only looking for a UICollectionView solution, I already have an alternative, because it will make my life much easier when converting to tvOS and using the focus stuff and navigating through 6 sections with 30+ buttons
Thank you very much for any help
You can register more that one kind of cell in UICollectionView:
If you are using Interface builder add another Collection View Cell from Objects library and set it's reuse identifier
Otherwise register nib or class in viewDidLoad method of your UICollectionViewController using self.collectionView?.registerNib(forCellWithReuseIdentifier:) or self.collectionView?.registerClass(forCellWithReuseIdentifier:)
Then when you dequeue cell use proper reuse identifier:
override func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell {
var reuseIdentifier = "identifier of cell with 8 button"
if indexPath.section == 0 {
reuseIdentifier = "identifier of start cell as you set in IB of viewDidLoad"
}
let cell = collectionView.dequeueReusableCellWithReuseIdentifier(reuseIdentifier, forIndexPath: indexPath)
// Configure the cell depending on indexPath
return cell
}
I'd go for 8 cells as buttons rather than using 1 cell with a series of UIButtons, that will keep things simple and allow you to use didSelectItemAtIndexPath. Can't you just use numberOfItemsInSection to define only 1 cell in the first section?
My approach would probably be to use a custom flow layout and a supplementary view for your background image and tap to start button - a bit complex but very flexible.
Working on a social iPhone app using Swift (with a Storyboard) and Parse where users can create posts and comment on posts similar to the Facebook iOS app and other social network apps.
The app has an initial, master Home Feed page (which displays user posts) and a detail Reply page (which displays user comments). Both use the PFTableViewController class and each of those table views have their own PFTableViewCell implemented in separate swift files as the prototype cells.
I am trying to send the content (username, post message, timestamp, etc) of a selected post cell from the master Home Feed page to the detail Reply page's topmost cell (the first cell at the top of the table view).
My goal is to have it work similar to the way the Facebook, Instagram, and Twitter iOS apps have it - whenever a user selects a post in the main feed/timeline, the detail view is shown where the main post is at the top (but not pinned to the top - meaning it will scroll up/down with the tableview) and its comments are in the cells beneath it.
I appreciate your help and time! Thank you!
On Selection on left panel, you can make tableview on right panel scroll to top animated false.
After further research, one way to "hack" it is by doing something similar to the following:
1) Create a custom tableview cell for the top row (topmost cell) by implementing it in a separate Swift file, just as you may have done for the prototype cell.
2) Now you have two custom cells. So implement two function where in each you customize them the way that serves your apps requirements, etc and the cell.
3) In the cellForRowAtIndexPath method, use an if/else statement to return the appropriate tableview cell for row 0 (topmost/header cell), otherwise return the other prototype cell for any other row (i.e.: the cells beneath the header cell):
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
if indexPath.row == 0 {
return headerCellAtIndexPath()
} else {
return commentCellAtIndexPath(indexPath)
}
}
func headerCellAtIndexPath() -> CommentsHeaderTableViewCell {
let headerCell = tableView.dequeueReusableCellWithIdentifier("topCell") as! CommentsHeaderTableViewCell
// Customize your headerCell...
return headerCell
}
func commentCellAtIndexPath(indexPath:NSIndexPath ) -> CommentTableViewCell {
let commentCell = tableView.dequeueReusableCellWithIdentifier("commentCell", forIndexPath: indexPath) as! CommentTableViewCell
// Customize your commentCell...
return commentCell
}