CODEWITHSUNDEEP
iosswiftuitableview
Jay
Jay

Reputation: 43

Why are my UITableViews misplaced on the y-axis when adding them programmatically?

I have as simple setup where I have a view controller embedded in a UINavigationController. On this view controller, I want to display multiple tableViews next to each other (horizontally). I am creating and adding the tableViews in viewDidLoad. It works well except that there is an issue with the y-position of every tableView except for the first one.

When creating the tableViews programmatically, the first tableView is always properly displayed right below the UINavigationBar. However all of the others are displayed "behind" the UINavigationBar even though the y-coordinate is equal to 0 in all of the tableViews.

This is what it looks like when you run it on the simulator (note that the tableView itself has a green backgroundColor):

enter image description here

And this is the code for it:

class ViewController: UIViewController {

    var tableViews: [UITableView] = [] // maintained only for debugging purposes

    override func viewDidLoad() {
        super.viewDidLoad()
        let tableViewCount: Int = 5
        createTableViews(tableViewCount)
    }

    override func viewDidAppear(animated: Bool) {
        super.viewDidAppear(animated)
        print(#function, tableViews)
    }

    func createTableView(count: Int) {
        let width = Int(self.view.bounds.width)/count

        for i in 0..<count {
            let x = width * i
            let y = 0
            let height = Int(view.bounds.height)
            let frame = CGRect(x: x, y: y , width: width, height: height)
            let tableView = UITableView(frame: frame, style: UITableViewStyle.Plain)
            tableView.backgroundColor = .greenColor()
            tableView.dataSource = self
            tableView.registerClass(UITableViewCell.self, forCellReuseIdentifier: "Cell")
            view.addSubview(tableView)
            tableView.tag = i

            tableViews.append(tableView)
        }
    }
}

I am only maintaining the tableViews property so that I can print them in viewDidAppear. The console output in viewDidAppear shows that all my tableViews have the same y position on their frames (= 0).

I did find an easy (yet hacky) fix for this. All I have to do is set the first y to 0 and the rest to 64 (which is the height of the status bar plus the height of the navigation bar). Like so:

let y = i == 0 ? 0 : 64

Does anyone have an idea why the tableViews are being misplaced? According to my understanding, all tableViews should be displayed right below the navigation bar, as this is the vertical origin of the view controller's view?

Upvotes: 1

Views: 202

Answers (1)

Connor Neville
Connor Neville

Reputation: 7361

According to my understanding, all tableViews should be displayed right below the navigation bar, as this is the vertical origin of the view controller's view?

This is only the case in my experience if you set myNavigationController.navigationBar.translucent = false. If the navigation bar is translucent, the top of your view is still the top of the screen.

On a side note, you should definitely look into laying these views out via auto layout, rather than this hacky frame math. Would simplify your code a lot.

Upvotes: 1

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