Question

在我的应用中，我允许用户通过选择器视图更改应用的颜色主题。在这样做时，诸如条和按钮之类的UI元素基于用户选择的内容而改变。

当视图关闭并重新打开时，我遇到了选择器视图返回第一个项目的问题。如何使选择器视图返回到用户先前选择的颜色？

以下是我目前为选择器视图提供的代码：

    func numberOfComponentsInPickerView(pickerView: UIPickerView!) -> Int {

    return 1
}

func pickerView(pickerView: UIPickerView!, numberOfRowsInComponent component: Int) -> Int {

    return coloursArray.count
}

func pickerView(pickerView: UIPickerView!, titleForRow row: Int, forComponent component: Int) -> String! {

    return coloursArray[row]
}

func pickerView(pickerView: UIPickerView!, didSelectRow row: Int, inComponent: Int) {
    colourSelected = row
    if colourSelected == 0 {
        self.navigationController.navigationBar.barTintColor = UIColor.newBlueColor()
        self.tabBarController.tabBar.selectedImageTintColor = UIColor.newBlueColor()
        UINavigationBar.appearance().barTintColor = UIColor.newBlueColor()
        UISegmentedControl.appearance().tintColor = UIColor.newBlueColor()
        changeButton.layer.backgroundColor = (UIColor.newBlueColor()).CGColor
    } else if colourSelected == 1 {
        self.navigationController.navigationBar.barTintColor = UIColor.newGreenColor()
        self.tabBarController.tabBar.selectedImageTintColor = UIColor.newGreenColor()
        UINavigationBar.appearance().barTintColor = UIColor.newGreenColor()
        UIButton.appearance().setTitleColor(UIColor.newGreenColor(), forState: UIControlState())
        UISegmentedControl.appearance().tintColor = UIColor.newGreenColor()
        changeButton.layer.backgroundColor = (UIColor.newGreenColor()).CGColor
    } else if colourSelected == 2 {
        self.navigationController.navigationBar.barTintColor = UIColor.newOrangeColor()
        self.tabBarController.tabBar.selectedImageTintColor = UIColor.newOrangeColor()
        UINavigationBar.appearance().barTintColor = UIColor.newOrangeColor()
        UISegmentedControl.appearance().tintColor = UIColor.newOrangeColor()
        changeButton.layer.backgroundColor = (UIColor.newOrangeColor()).CGColor
    } else if colourSelected == 3 {
        self.navigationController.navigationBar.barTintColor = UIColor.newPurpleColor()
        self.tabBarController.tabBar.selectedImageTintColor = UIColor.newPurpleColor()
        UINavigationBar.appearance().barTintColor = UIColor.newPurpleColor()
        UISegmentedControl.appearance().tintColor = UIColor.newPurpleColor()
        changeButton.layer.backgroundColor = (UIColor.newPurpleColor()).CGColor
    } else if colourSelected == 4 {
        self.navigationController.navigationBar.barTintColor = UIColor.newRedColor()
        self.tabBarController.tabBar.selectedImageTintColor = UIColor.newRedColor()
        UINavigationBar.appearance().barTintColor = UIColor.newRedColor()
        UISegmentedControl.appearance().tintColor = UIColor.newRedColor()
        changeButton.layer.backgroundColor = (UIColor.newRedColor()).CGColor
    } else if colourSelected == 5 {
        self.navigationController.navigationBar.barTintColor = UIColor.newTurquoiseColor()
        self.tabBarController.tabBar.selectedImageTintColor = UIColor.newTurquoiseColor()
        UINavigationBar.appearance().barTintColor = UIColor.newTurquoiseColor()
        UISegmentedControl.appearance().tintColor = UIColor.newTurquoiseColor()
        changeButton.layer.backgroundColor = (UIColor.newTurquoiseColor()).CGColor
    }
}

Answer 1

假设您的选择器中有一列（＆＃34;组件＆＃34;）：

override func viewDidLoad() {
   super.viewDidLoad()
   let idx = NSUserDefaults.standardUserDefaults().integerForKey("SavedIndex")
   pickerView.selectRow(idx, inComponent: 0, animated: false)
}

当然，选择行时保存到NSUserDefaults。

根据您的设置，您可能需要将其放入viewWillAppear()。

将选择器视图返回到先前选定的行

1 个答案: