使用swift以编程方式向从父类继承的子类的uitableview添加前导和尾随空格

Question

I am trying to add leading and trailing spaces to tableview embedded in view programmatically. This tableview has constraints been declared in parent class i am trying to override them in child class. I am doing in the following way

class TestTableView: BaseTableViewController{

override func viewDidAppear(_ animated: Bool) {
    super.viewDidAppear(animated)
    self.lpBaseTableView.frame = CGRect(x: 0, y: 0, width: self.view.frame.size.width, height: self.lpBaseTableView.contentSize.height)
    self.lpBaseTableView.center = self.view.center
    self.lpBaseTableView.translatesAutoresizingMaskIntoConstraints = false
    self.lpBaseTableView.leadingAnchor.constraint(equalTo: self.view.leadingAnchor, constant: 16).isActive = true
    self.lpBaseTableView.trailingAnchor.constraint(equalTo: self.view.trailingAnchor, constant: 16).isActive = true

 }
}

After researching few links from stack overflow i am using the above code but there is no change in the table view position as shown below in the image. Please help me out. I am new to swift and iOS

Answer 1

Adding a leading and trailing constraints are simple, just give proper constants with respect to the superview and also give top and bottom constraints. Frame and centre is not needed since you're using autolayout here.

    lpBaseTableView = UITableView()
    lpBaseTableView.translatesAutoresizingMaskIntoConstraints = false
    view.addSubview(lpBaseTableView)

    NSLayoutConstraint.activate([
        lpBaseTableView.leadingAnchor.constraint(equalTo: view.leadingAnchor, constant: 16),
        lpBaseTableView.trailingAnchor.constraint(equalTo: view.trailingAnchor, constant: -16),
        lpBaseTableView.topAnchor.constraint(equalTo: view.topAnchor),
        lpBaseTableView.bottomAnchor.constraint(equalTo: view.bottomAnchor)
    ]) 

Answer 2

You can try with SnaKit

    import SnapKit

    lpBaseTableView.snp.makeConstraints { (make) in
    make.center.equalTo(view)
    make.left.equalTo(view.snp.left)
    make.right.equalTo(view.snp.right)

Please note that if there is also constraints from Storyboard for same object it could not work properly