Swift-刷新自定义UITabBarController栏

Question

我有一个自定义的TabBar，在TabBar上方有一个凸起的中间按钮。当用户还没有完成日常任务时，应该显示setupIncompleteMiddleButton((，表明这一点。但是，一旦用户完成了任务，我希望出现setupCompleteMiddleButton((，表示已经完成了任务。我不知道该怎么做——我不应该在控制器中调用viewDidLoad((，当调用它时，它不会刷新视图。刷新TabBar没有任何作用。

这是我的TabBar控制器：

class TabBarController: UITabBarController, UITabBarControllerDelegate {
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)!
}
override func viewDidLoad() {
super.viewDidLoad()
// This is where I currently decide which button to show the "complete" one if the task is done, and the incomplete one if not. 
self.delegate = self
if UserData.hasCompletedDailyTask() == true {
setupCompleteMiddleButton()
} else {
setupIncompleteMiddleButton()
}
}
// Incomplete button 
func setupIncompleteMiddleButton() {
let middleButton = UIButton(frame: CGRect(x: (self.view.bounds.width / 2) - 25, y: -20, width: 50, height: 50))

middleButton.backgroundColor = UIColor.systemYellow
middleButton.setImage(UIImage(systemName: "sun.max.fill"), for: .normal)
middleButton.imageView?.tintColor = UIColor.white
middleButton.layer.cornerRadius = middleButton.frame.width / 2
middleButton.clipsToBounds = true

self.tabBar.addSubview(middleButton)
middleButton.addTarget(self, action: #selector(self.middleButtonAction), for: .touchUpInside)
self.view.layoutIfNeeded()
}
// Complete button
func setupCompleteMiddleButton() {
let middleButton = UIButton(frame: CGRect(x: (self.view.bounds.width / 2) - 25, y: -20, width: 50, height: 50))
middleButton.backgroundColor = UIColor.systemGreen
middleButton.setImage(UIImage(systemName: "checkmark"), for: .normal)
middleButton.imageView?.tintColor = UIColor.white
middleButton.layer.cornerRadius = middleButton.frame.width / 2
middleButton.clipsToBounds = true
self.tabBar.addSubview(middleButton)
middleButton.addTarget(self, action: #selector(self.middleButtonAction), for: .touchUpInside)
self.view.layoutIfNeeded()
}
@objc func middleButtonAction(sender: UIButton) {
self.selectedIndex = 1  
}
}

谢谢！

Answer 1

您可以对按钮的全局单个对象进行尝试，并在任务完成或未完成时更改图像。

class TabBarController: UITabBarController, UITabBarControllerDelegate {
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)!
}
// TabbarController hode this button
var middleButton: UIButton!
override func viewDidLoad() {
super.viewDidLoad()
setupButton()
// This is where I currently decide which button to show the "complete" one if the task is done, and the incomplete one if not.
self.delegate = self
// taskCompletion is a call back when UserData finish its task
if UserData.taskCompletion {
setupCompleteMiddleButton()
} else {
setupIncompleteMiddleButton()
}
}
func setupButton() {
middleButton = UIButton(frame: CGRect(x: (self.view.bounds.width / 2) - 25, y: -20, width: 50, height: 50))
middleButton.backgroundColor = UIColor.systemYellow
middleButton.layer.cornerRadius = middleButton.frame.width / 2
middleButton.clipsToBounds = true
self.tabBar.addSubview(middleButton)
middleButton.addTarget(self, action: #selector(self.middleButtonAction), for: .touchUpInside)
self.view.layoutIfNeeded()
}
//  Incomplete button
func setupIncompleteMiddleButton() {
middleButton.backgroundColor = UIColor.systemYellow
middleButton.setImage(UIImage(systemName: "sun.max.fill"), for: .normal)

}
// Complete button
func setupCompleteMiddleButton() {
// change button color and image
middleButton.backgroundColor = UIColor.systemGreen
middleButton.setImage(UIImage(systemName: "checkmark"), for: .normal)
}
@objc func middleButtonAction(sender: UIButton) {
self.selectedIndex = 1
}

Answer 2

也许你可以试试这个：

import UIKit
class TabBarController: UITabBarController, UITabBarControllerDelegate {

required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)!
}

// TabbarController hode this button
var middleButton: UIButton!
override func viewDidLoad() {
super.viewDidLoad()

// This is where I currently decide which button to show the "complete" one if the task is done, and the incomplete one if not.
self.delegate = self
// taskCompletion is a call back when UserData finish its task
if UserData.taskCompletion {
setupCompleteMiddleButton()
}
setupIncompleteMiddleButton()
}

//  Incomplete button 
func setupIncompleteMiddleButton() {
// initialize button  
middleButton = UIButton(frame: CGRect(x: (self.view.bounds.width / 2) - 25, y: -20, width: 50, height: 50))
middleButton.backgroundColor = UIColor.systemYellow
middleButton.setImage(UIImage(systemName: "sun.max.fill"), for: .normal)
middleButton.imageView?.tintColor = UIColor.white
middleButton.layer.cornerRadius = middleButton.frame.width / 2
middleButton.clipsToBounds = true
self.tabBar.addSubview(middleButton)
middleButton.addTarget(self, action: #selector(self.middleButtonAction), for: .touchUpInside)
self.view.layoutIfNeeded()
}

// Complete button
func setupCompleteMiddleButton() {
// change button color and image
middleButton.backgroundColor = UIColor.systemGreen
middleButton.setImage(UIImage(systemName: "checkmark"), for: .normal)
}

@objc func middleButtonAction(sender: UIButton) {
self.selectedIndex = 1
}
}