How can I dynamically add additional text fields to a view based on the response to previous question which is a drop down with set list of options.
The issue I am having is with dynamic positioning. For example if I place the field beneath but keep it hidden and show when an option is selected that only works one way. What if I select the other option how can I use the same space to show a different question/text field?
Of course I could overlay all of the options in their positions and show/hide. But is there a better way to build a dynamic form with conditional logic for questions?
Diagram:
If it were me, to make it simple for both myself and the viewer, I would have predefined space. Say, 20% of the view. Then, add questions to the scrollView variably, depending on the situation. The user can then scroll through that view.
let rect = CGRect(x: view.frame.width*0.1, y: someHeightDownInTheView, width: view.frame.width*0.8, height: view.frame.height*0.2)
let scrollView = UIScrollView(frame: rect)
let questions = ["Do I want to be a unicorn"]
if(question2.answer == "A") {
questions.append("Do I want to be a fairy princess")
}
//...Specific options
for question in questions {
let label:UILabel = createQuestion(name: "someName", question: question)
let answer:UITextView = createAnswer(name: "someName")
scrollView.addSubview(label)
scrollView.addSubview(answer)
}
func createQuestion(name: String, question: String) -> UILabel {
//Create a question with a UILabel of some SET SIZE
}
func createAnswer(name: String) -> UITextView {
//Create answer with a UITextView of some SIZE
}
There are various ways to handle variable numbers of fields.
You could create a table view or collection view, and have each cell, or each grouped set of cells, represent a question and its text field.
You could also use a vertical stack view. You can add or remove items from a stack view and it updates make room for/close up empty space as needed.
There are tons of examples of both approaches online. Which is the best fit depends on the details, but if you only ever have at most 2 questions/answers on-screen then maybe a stack view is the way to go.
Related
As a technical assessment for a job I'm interviewing for, I'm making a basic word search game, where the user looks for translations of a given word in a given language. I've got a fair amount of iOS experience, but I've never done dynamically-generated views with run-time-determined text labels, etc. before.
To be clear, I know this is a job assessment, but regardless of whether I get the job, or whether I'm even able to finish the assessment in time, I think this is an interesting problem and I'd like to learn how to do this, so I'll be finishing this as an app to run in the simulator or on my own phone.
So. I have a view embedded in/controlled by a UINavigationController. I have a couple of informational labels at the top, a set of buttons to perform actions across the bottom of the view, and the main view area needs to contain a 2D grid of characters. I'd like to be able to take an action when a character is tapped, such as highlight the character if it's part of a valid word. I'd like to be able to support grids of different sizes, so I can't just create an autolayout-constrained grid of labels or buttons in Interface Builder.
I've tried various methods for displaying the 2D grid of characters, but the one I thought had the most promise was as follows:
Use a UITableView to represent the rows of characters. Inside each table view cell, use a UIStackView with a dynamically generated collection of UILabels.
To fill my UITableView, I have the following:
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = gameGrid.dequeueReusableCell(withIdentifier: "GameGridCell") as! TWSGameGridCell
if indexPath.row < word.grid.count {
cell.characters = word.grid[indexPath.row]
cell.configureCell()
return cell
}
return cell
}
The function in the custom table cell class that configures the cell (ideally to create and display the row of characters) is this:
func configureCell()
{
self.stackView = UIStackView(arrangedSubviews: [UILabel]())
self.stackView.backgroundColor = (UIApplication.shared.delegate as! TWSAppDelegate).appBackgroundColor()
self.stackView.distribution = .fillEqually
let myRect = self.frame
self.stackView.frame = myRect
let characterGridWidth = myRect.width / CGFloat(characters.count)
for cIndex in 0..<characters.count {
let labelRect = CGRect(x: myRect.origin.x + (CGFloat(cIndex) * characterGridWidth), y: myRect.origin.y, width: CGFloat(characterGridWidth), height: myRect.height)
let currentLabel = UILabel(frame: labelRect)
currentLabel.backgroundColor = (UIApplication.shared.delegate as! TWSAppDelegate).appBackgroundColor()
currentLabel.textColor = (UIApplication.shared.delegate as! TWSAppDelegate).appTextColor()
currentLabel.font = UIFont(name: "Palatino", size: 24)
currentLabel.text = characters[cIndex]
self.stackView.addArrangedSubview(currentLabel)
}
}
My guess is that it's running into trouble in that the labels have no visible rect when they're created, so they don't display anywhere.
The resulting view when run in the simulator is a white box covering as many rows of the table view as should be filled with rows of characters, and the rest of the table view shows with the custom background color I'm using), as per this image:
What I'm trying for is for that white box to have the same background color as everything else, and be filled with rows of characters. What am I missing?
Problem might be about adding 'labelRect', you already specify the rect of your stackView. I think regardless of the frame of labels, stackView should naturally be able to create it's inner labels and distribute them inside of itself.
Also can you add the following, after you initialize your stackView, inside your configureCell method:
self.stackView.axis = .horizontal
Edit: from the comment below, the solution was to create the labels (though I switched to buttons for further functionality), add them all to a [UIButton], then use that to create the UIStackView (self.stackView = UIStackView(arrangedSubviews: buttons)).
I'm creating an app that needs to show a tableview like below image
Similar colored circles are to be matched with a line.
Which view i can add the lines?
Or need to create a new view above tableview? But still my tableview needs to be scrolled.
How can i achieve this?
Update for Bounty
I want to implement the same with incliend lines between neighbouring circles. How to achieve the same?
Demonstration below:
create design like this
Based on your requirement just hide upper line and lower line of circle
You need to create collection view in tableview cell. In collection view you create one cell. Design the same user interface like your design. Show and hide the view with matching of rule. It will not affect tableview scrolling. and with this approach you can also provide scroll in collection view cell. i can provide you coded solution if you able to provide me more information. Thanks
You can use this Third Party LIb
You need to use a combination of collection view and a table view to give support for all devices.
1.Create one collection view cell with following layout
Hide upper and lower lines as per your need
Add collection view in table view cell and managed a number of cells in collection view depending upon the current device width and item's in between spacing.
You can create a vertical label without text, set the background color with black and place it behind the circle in view hierarchy and set a width of the label as per your requirement. Then you can hide unhide the label whenever you want.
P.S.: Make sure to hide your cell separator.
I have created a demo project. You can find it here. I tried to match your requirements. You can update the collection view settings to handle the hide and show of labels.
Let me know if you have any questions.
Hope this help.
Thanks!
To connect any circle with any other circle in the cell above / below, it will be easier and cleaner to create the connection lines dynamically rather than building them into the asset as before. This part is simple. The question now is where to add them.
You could have the connection lines between every two cells be contained in the top or bottom cell of each pair, since views can show content beyond their bounds.
There's a problem with this though, regardless of which cell contains the lines. For example, if the top cell contains them, then as soon as it is scrolled up off screen, the lines will disappear when didEndDisplayingCell is called, even though the bottom cell is still completely on screen. And then scrolling slightly such that cellForRow is called, the lines will suddenly appear again.
If you want to avoid that problem, then here is one approach:
One Approach
Give your table view and cells a clear background color, and have another table view underneath to display a new cell which will contain the connection lines.
So you now have a background TVC, with a back cell, and a foreground TVC with a fore cell. You add these TVC's as children in a parent view controller (of which you can set whatever background color you like), disable user interaction on the background TVC, and peg the background TVC's content offset to the foreground TVC's content offset in an observation block, so they will stay in sync when scrolling. I've done this before; it works well. Use the same row height, and give the background TVC a top inset of half the row height.
We can make the connection lines in the back cell hug the top and bottom edges of the cell. This way circles will be connected at their centre.
Perhaps define a method in your model that calculates what connections there are, and returns them, making that a model concern.
extension Array where Element == MyModel {
/**
A connection is a (Int, Int).
(0, 0) means the 0th circle in element i is connected to the 0th circle in element j
For each pair of elements i, j, there is an array of such connections, called a mesh.
Returns n - 1 meshes.
*/
func getMeshes() -> [[(Int, Int)]] {
// Your code here
}
}
Then in your parent VC, do something like this:
class Parent_VC: UIViewController {
var observation: NSKeyValueObservation!
var b: Background_TVC!
override func viewDidLoad() {
super.viewDidLoad()
let b = Background_TVC(model.getMeshes())
let f = Foreground_TVC(model)
for each in [b, f] {
self.addChild(each)
each.view.frame = self.view.bounds
self.view.addSubview(each.view)
each.didMove(toParent: self)
}
let insets = UIEdgeInsets(top: b.tableView.rowHeight / 2, left: 0, bottom: 0, right: 0)
b.tableView.isUserInteractionEnabled = false
b.tableView.contentInset = insets
self.b = b
self.observation = f.tableView.observe(\.contentOffset, options: [.new]) { (_, change) in
let y = change.newValue!.y
self.b.tableView.contentOffset.y = y // + or - half the row height
}
}
}
Then of course there's your drawing code. You could make it a method of your back cell class (a custom cell), which will take in a mesh data structure and then draw the lines that represent it. Something like this:
class Back_Cell: UITableViewCell {
/**
Returns an image with all the connection lines drawn for the given mesh.
*/
func createMeshImage(for mesh: [(Int, Int)]) -> UIImage {
let canvasSize = self.contentView.bounds.size
// Create a new canvas
UIGraphicsBeginImageContextWithOptions(canvasSize, false, 0)
// Grab that canvas
let canvas = UIGraphicsGetCurrentContext()!
let spacing: CGFloat = 10.0 // whatever the spacing between your circles is
// Draw the lines
for each in mesh {
canvas.move(to: CGPoint(x: CGFloat(each.0) * spacing, y: 0))
canvas.addLine(to: CGPoint(x: CGFloat(each.1) * spacing, y: self.contentView.bounds.height))
}
canvas.setStrokeColor(UIColor.black.cgColor)
canvas.setLineWidth(3)
canvas.strokePath()
let image = UIGraphicsGetImageFromCurrentImageContext()!
UIGraphicsEndImageContext()
return image
}
}
You'd probably want to create a Mesh class and store the images in that model, to avoid redrawing.
I have multiple inputs that are disabled/enabled based on certain conditions — is there a way to select the adjacent UILabel that is in the same view?
Here's a visual the UITextField/UILabel:
You can find any views in a view with a simple loop.
for view in view.subviews {
if let label = view as? UILabel {
// do something with your view
}
}
Use viewWithTag option ,give specific tag to textField and fetch them
if let theTextField = self.view.viewWithTag(1) as? UITextField {
print(theTextField.text)
}
I don't think there is a direct way of identifying the adjacent label for a field. You'd have to loop through the labels looking for one in the correct position.
Instead give your text fields tags 1-10, and give your labels corresponding tags 101-110.
Then use the tag number to find the label.
I've tried a lot of things but couldn't come up with a solution. Any words of thought can help me evaluate on this. I made a full view DrawBoard class which is inherited from a UITextView class.When the switch on the view controller is on the user can type and scroll, when it is off the user can draw on the Drawboard.
#IBAction func changeSwitch(sender: UISwitch) {
if sender.on{
drawBoard.setNeedsDisplay()
drawBoard.scrollEnabled = true
drawBoard.editable = true
drawBoard.selectable = true
drawBoard.switchBool = false
}else if !sender.on {
drawBoard.switchBool=true
let a:CGPoint = drawBoard.contentOffset
drawBoard.scrollEnabled = false
drawBoard.setContentOffset(a, animated: false)
drawBoard.editable = false
drawBoard.selectable=false
}
}
It updates the scrolling but scrollEnabled= false just saves the text that is in the first page range of the textview so that it scrolls to the top automatically and disable the scrolling there.Then when I do the setContentOffset the drawable view of the background is visible and it draws on the right place of the textview. However the text that should be on top of it is not visible. This only happens when the switch button is set to off while I am out of the first page's range.How do I also make the text at that range visible?
Sorry if it's a really easy question I'm new to programming and got stuck for a considerable amount of time for this.Thank you.
You have to update the content size of the UIScrollView.
Like this:
scrollView.contentSize = CGSize(width: 100, height: 100)
"Content Size" determines the size of scrollable content, if it's not large enough to cover new views, you won't be able to see it in your scroll view.
when I update segmented control text, the interface (segment's width) changed and cut some letters.
[segmentedcontoll setTitle:#"test" forSegmentAtIndex:1];
segmentedcontoll.apportionsSegmentWidthsByContent = YES;
How can I solve this ?
EDIT:
It looks like your content has outgrown the dimensions of the standard UISegmentedControl.
If you are okay with smaller font, it's possible to set the entire control to have a smaller font point size, seen here.
Another option is to configure the segments the other supported way.. With images. It's a little bit of a hack, but you can create images on the fly with the UIView Snapshotting API of views/labels configured however you want and set images for each segment instead of using text. This would allow you to create 2 line labels with fixed widths and set images for each section to be images generated from the label as the content changes. More work, but you would still be using the standard class.
The last option, which might work the best for you, is to create some other custom control that does what you would like. After all, UISegmentedControl really is just a nice button container. And it does somewhat seem like you are using the control in a non-standard way - both as a control and an input form section.
Others have gone this route before and created alternatives that you can use.
You can create a separate class as below,
class CustomSegmentedControl: UISegmentedControl {
//code for creating multi line
override func didMoveToSuperview()
{
for segment in subviews
{
for subview in segment.subviews
{
if let segmentLabel = subview as? UILabel
{
segmentLabel.numberOfLines = 0 //just change here the number of lines and check it.
}
}
}
}
}
and create an outlet in your viewcontroller as,
// Initialize
let items = ["Purple", "Green", "New Segment"]
let customSC = CustomSegmentedControl(items: items)
use customSC and do what ever you want to do, similar to segmentedControl object.