以编程方式创建一个可用于横向和纵向的UIPickerView

Question

我想创建一个最小的UIPickerView，它在纵向和横向格式中都很好看，它成功了。。。有点。我在按下按钮后添加pickerView，完成后将其隐藏。pickerView工作正常：

• 当我以纵向或横向启动应用程序并按下按钮而不改变方向时
• 当屏幕上显示pickerView时，更改方向效果良好，pickerView更改大小

但是，当在一个方向上启动并在单击按钮显示pickerView之前更改方向时，它不会很好地工作，然后会显示以下内容：在门户方向以支付为导向的

以下是代码（单视图应用程序，故事板中只有一个按钮：myButton，带有向下触摸操作touchMyButton）

class myViewController: UIViewController, UIPickerViewDataSource, UIPickerViewDelegate {
@IBOutlet weak var myButton: UIButton!
var myPickerView: UIPickerView! = UIPickerView(frame:CGRectMake(0.0, 0.0, UIScreen.mainScreen().bounds.width, 162))
var activePickerView: Int = 0
override func viewDidLoad() {
    super.viewDidLoad()
    myPickerView.tag = 1
    myPickerView.delegate = self
    myPickerView.autoresizingMask = [.FlexibleWidth]
}
override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
}

@IBAction func touchMyButton(sender: AnyObject) {
    if (activePickerView == 0)
    {
        activePickerView = myPickerView.tag
        myPickerView.selectRow(5, inComponent:0, animated:false)
        myPickerView.backgroundColor = UIColor.init(white:0.80, alpha:0.80)
        myPickerView.frame = CGRectMake(0.0, 100.0, UIScreen.mainScreen().bounds.width, 0.0)
        self.view.layoutIfNeeded()
        self.view.addSubview(myPickerView)
        myPickerView.setNeedsDisplay()
        UIView.animateWithDuration(0.5, delay:0.0, options:UIViewAnimationOptions.CurveEaseInOut, animations:{
            self.view.layoutIfNeeded()
            self.myPickerView.frame = CGRectMake(0.0, 100.0, self.myPickerView.frame.width, 162)
            }, completion: { _ in
        })
    }
    else
    {
        self.selectPickerView()
    }
}
func selectPickerView(){
    if (activePickerView == myPickerView.tag)
    {
        let _ = myPickerView.selectedRowInComponent(0)
        let framePV = self.myPickerView.frame
        UIView.animateWithDuration(0.5, delay:0.0, options:UIViewAnimationOptions.CurveEaseInOut, animations:{
            self.view.layoutIfNeeded()
            self.myPickerView.frame = CGRectMake(0.0, framePV.origin.y, framePV.width, 0.0 )
            }, completion:{ _ in
                self.myPickerView.removeFromSuperview()
        })
    }
    activePickerView = 0
}
// MARK: UIPickerViewDataSource methods
func numberOfComponentsInPickerView(pickerView: UIPickerView) -> Int
{   return 1    }
func pickerView(pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int
{   return 10   }
func pickerView(pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String?
{   return "Row (row)" }
func pickerView(pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
    activePickerView = pickerView.tag
    selectPickerView()
}

override func didRotateFromInterfaceOrientation(fromInterfaceOrientation: UIInterfaceOrientation)
{   self.view.layoutIfNeeded()  }
}

我迷路了，我不知道我能做些什么来让它工作

Answer 1

谢谢，我是在有约束的情况下完成的（这不是很简单），就像一样

import UIKit
class myViewController: UIViewController, UIPickerViewDataSource, UIPickerViewDelegate {
@IBOutlet weak var myButton: UIButton!
var myPickerView: UIPickerView! = UIPickerView()
var activePickerView: Int = 0
override func viewDidLoad() {
    super.viewDidLoad()
    myPickerView.tag = 1
    myPickerView.delegate = self
}
override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
}
@IBAction func touchMyButton(sender: AnyObject) {
    if (activePickerView == 0){
        activePickerView = myPickerView.tag
        myPickerView.selectRow(5, inComponent:0, animated:false)
        myPickerView.backgroundColor = UIColor.init(white:0.80, alpha:0.80)
        myPickerView.translatesAutoresizingMaskIntoConstraints = false
        self.view.addSubview(myPickerView)
        let margins = self.view.layoutMarginsGuide
        let topC = myPickerView.topAnchor.constraintEqualToAnchor(topLayoutGuide.topAnchor, constant: 100.0)
        let leadingC = myPickerView.leadingAnchor.constraintEqualToAnchor(margins.leadingAnchor)
        let trailingC = myPickerView.trailingAnchor.constraintEqualToAnchor(margins.trailingAnchor)
        let heightC = myPickerView.heightAnchor.constraintEqualToConstant(0.0)
        heightC.identifier = "height"
        NSLayoutConstraint.activateConstraints([topC, leadingC, trailingC, heightC])
        self.view.layoutIfNeeded()
        myPickerView.setNeedsLayout()
        heightC.constant = 162.0
        UIView.animateWithDuration(0.5, delay:0.0, options:UIViewAnimationOptions.CurveEaseInOut, animations:{
            self.view.layoutIfNeeded()
            }, completion: { _ in
        })
    }
    else {
        self.selectPickerView()
    }
}
func selectPickerView(){
    if (activePickerView == myPickerView.tag)
    {
        let _ = myPickerView.selectedRowInComponent(0)
        for constraint in myPickerView.constraints
        {
            if constraint.identifier == "height"
            {   constraint.constant = 0.0   }
        }
        myPickerView.setNeedsLayout()
        UIView.animateWithDuration(0.5, delay:0.0, options:UIViewAnimationOptions.CurveEaseInOut, animations:{
            self.view.layoutIfNeeded()
            }, completion:{ _ in
                self.myPickerView.removeConstraints(self.myPickerView.constraints)
                self.myPickerView.removeFromSuperview()
        })
    }
    activePickerView = 0
}
// MARK: UIPickerViewDataSource methods
func numberOfComponentsInPickerView(pickerView: UIPickerView) -> Int
{   return 1    }
func pickerView(pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int
{   return 10   }
func pickerView(pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String?
{   return "Row (row)" }
func pickerView(pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
    activePickerView = pickerView.tag
    selectPickerView()
}
}

我不喜欢丢弃pickerView的动画（我不知道为什么它与显示它的动画不完全相反），但它很有效。我可能会在将来使用不透明视图来覆盖pickerView。