当用户在消息视图中注册或登录时，我如何在以下代码中使用活动指标。
下面的代码是一个登录controller，可以处理用户的登录和注册。
因此，每当用户键入登录或注册按钮时，我如何使用活动指示器查看或进度查看。
class LoginController: UIViewController {
var messagesController: MessagesController?
let inputsContainerView: UIView = {
let view = UIView()
view.backgroundColor = UIColor(r: 209, g:238, b:252).withAlphaComponent(0.3)
view.translatesAutoresizingMaskIntoConstraints = false
view.layer.cornerRadius = 5
view.layer.masksToBounds = true
return view
}()
lazy var loginRegisterButton: UIButton = {
let button = UIButton(type: .system)
button.backgroundColor = UIColor(r: 255, g: 45, b: 85)
button.setTitle("Register", for: UIControlState())
button.translatesAutoresizingMaskIntoConstraints = false
button.setTitleColor(UIColor.white, for: UIControlState())
button.titleLabel?.font = UIFont.boldSystemFont(ofSize: 16)
button.layer.cornerRadius = 10
button.addTarget(self, action: #selector(handleLoginRegister), for: .touchUpInside)
return button
}()
func handleLoginRegister() {
if loginRegisterSegmentedControl.selectedSegmentIndex == 0 {
handleLogin()
} else {
handleRegister()
}
}
func handleLogin() {
guard let email = emailTextField.text, let password = passwordTextField.text else {
print("Form is not valid")
return
}
FIRAuth.auth()?.signIn(withEmail: email, password: password, completion: { (user, error) in
if error != nil {
print(error ?? "")
return
}
//successfully logged in our user
self.messagesController?.fetchUserAndSetupNavBarTitle()
self.dismiss(animated: true, completion: nil)
})
}
// TextField, EmailTextField, PasswordTextField, seperator view
let nameTextField: UITextField = {
let tf = UITextField()
tf.placeholder = "Name"
tf.translatesAutoresizingMaskIntoConstraints = false
return tf
}()
let nameSeparatorView: UIView = {
let view = UIView()
view.backgroundColor = UIColor(r: 220, g: 220, b: 220)
view.translatesAutoresizingMaskIntoConstraints = false
return view
}()
let emailTextField: UITextField = {
let tf = UITextField()
tf.placeholder = "Email"
tf.translatesAutoresizingMaskIntoConstraints = false
return tf
}()
let emailSeparatorView: UIView = {
let view = UIView()
view.backgroundColor = UIColor(r: 220, g: 220, b: 220)
view.translatesAutoresizingMaskIntoConstraints = false
return view
}()
let passwordTextField: UITextField = {
let tf = UITextField()
tf.placeholder = "Password"
tf.translatesAutoresizingMaskIntoConstraints = false
tf.isSecureTextEntry = true
return tf
}()
lazy var profileImageView: UIImageView = {
let imageView = UIImageView()
imageView.image = UIImage(named: "backslash_inc02main")
imageView.translatesAutoresizingMaskIntoConstraints = false
imageView.contentMode = .scaleAspectFill
imageView.layer.cornerRadius = 20
imageView.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(handleSelectProfileImageView)))
imageView.isUserInteractionEnabled = true
return imageView
}()
lazy var loginRegisterSegmentedControl: UISegmentedControl = {
let sc = UISegmentedControl(items: ["Login", "Register"])
sc.translatesAutoresizingMaskIntoConstraints = false
sc.tintColor = UIColor.white
sc.selectedSegmentIndex = 1
sc.addTarget(self, action: #selector(handleLoginRegisterChange), for: .valueChanged)
return sc
}()
func handleLoginRegisterChange() {
let title = loginRegisterSegmentedControl.titleForSegment(at: loginRegisterSegmentedControl.selectedSegmentIndex)
loginRegisterButton.setTitle(title, for: UIControlState())
// change height of inputContainerView, but how???
inputsContainerViewHeightAnchor?.constant = loginRegisterSegmentedControl.selectedSegmentIndex == 0 ? 100 : 150
// change height of nameTextField
nameTextFieldHeightAnchor?.isActive = false
nameTextFieldHeightAnchor = nameTextField.heightAnchor.constraint(equalTo: inputsContainerView.heightAnchor, multiplier: loginRegisterSegmentedControl.selectedSegmentIndex == 0 ? 0 : 1/3)
nameTextFieldHeightAnchor?.isActive = true
nameTextField.isHidden = loginRegisterSegmentedControl.selectedSegmentIndex == 0
emailTextFieldHeightAnchor?.isActive = false
emailTextFieldHeightAnchor = emailTextField.heightAnchor.constraint(equalTo: inputsContainerView.heightAnchor, multiplier: loginRegisterSegmentedControl.selectedSegmentIndex == 0 ? 1/2 : 1/3)
emailTextFieldHeightAnchor?.isActive = true
passwordTextFieldHeightAnchor?.isActive = false
passwordTextFieldHeightAnchor = passwordTextField.heightAnchor.constraint(equalTo: inputsContainerView.heightAnchor, multiplier: loginRegisterSegmentedControl.selectedSegmentIndex == 0 ? 1/2 : 1/3)
passwordTextFieldHeightAnchor?.isActive = true
}
override func viewDidLoad() {
super.viewDidLoad()
//view.backgroundColor = UIColor(r: 255, g: 149, b: 0)
self.view.addBackground()
view.addSubview(inputsContainerView)
view.addSubview(loginRegisterButton)
view.addSubview(profileImageView)
view.addSubview(loginRegisterSegmentedControl)
setupInputsContainerView()
setupLoginRegisterButton()
setupProfileImageView()
setupLoginRegisterSegmentedControl()
}
func setupLoginRegisterSegmentedControl() {
//need x, y, width, height constraints
loginRegisterSegmentedControl.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
loginRegisterSegmentedControl.bottomAnchor.constraint(equalTo: inputsContainerView.topAnchor, constant: -12).isActive = true
loginRegisterSegmentedControl.widthAnchor.constraint(equalTo: inputsContainerView.widthAnchor, multiplier: 1).isActive = true
loginRegisterSegmentedControl.heightAnchor.constraint(equalToConstant: 36).isActive = true
}
func setupProfileImageView() {
//need x, y, width, height constraints
profileImageView.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
profileImageView.bottomAnchor.constraint(equalTo: loginRegisterSegmentedControl.topAnchor, constant: -12).isActive = true
profileImageView.widthAnchor.constraint(equalToConstant: 150).isActive = true
profileImageView.heightAnchor.constraint(equalToConstant: 150).isActive = true
}
var inputsContainerViewHeightAnchor: NSLayoutConstraint?
var nameTextFieldHeightAnchor: NSLayoutConstraint?
var emailTextFieldHeightAnchor: NSLayoutConstraint?
var passwordTextFieldHeightAnchor: NSLayoutConstraint?
func setupInputsContainerView() {
//need x, y, width, height constraints
inputsContainerView.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
inputsContainerView.centerYAnchor.constraint(equalTo: view.centerYAnchor).isActive = true
inputsContainerView.widthAnchor.constraint(equalTo: view.widthAnchor, constant: -24).isActive = true
inputsContainerViewHeightAnchor = inputsContainerView.heightAnchor.constraint(equalToConstant: 150)
inputsContainerViewHeightAnchor?.isActive = true
inputsContainerView.addSubview(nameTextField)
inputsContainerView.addSubview(nameSeparatorView)
inputsContainerView.addSubview(emailTextField)
inputsContainerView.addSubview(emailSeparatorView)
inputsContainerView.addSubview(passwordTextField)
//need x, y, width, height constraints
nameTextField.leftAnchor.constraint(equalTo: inputsContainerView.leftAnchor, constant: 12).isActive = true
nameTextField.topAnchor.constraint(equalTo: inputsContainerView.topAnchor).isActive = true
nameTextField.widthAnchor.constraint(equalTo: inputsContainerView.widthAnchor).isActive = true
nameTextFieldHeightAnchor = nameTextField.heightAnchor.constraint(equalTo: inputsContainerView.heightAnchor, multiplier: 1/3)
nameTextFieldHeightAnchor?.isActive = true
//need x, y, width, height constraints
nameSeparatorView.leftAnchor.constraint(equalTo: inputsContainerView.leftAnchor).isActive = true
nameSeparatorView.topAnchor.constraint(equalTo: nameTextField.bottomAnchor).isActive = true
nameSeparatorView.widthAnchor.constraint(equalTo: inputsContainerView.widthAnchor).isActive = true
nameSeparatorView.heightAnchor.constraint(equalToConstant: 1).isActive = true
//need x, y, width, height constraints
emailTextField.leftAnchor.constraint(equalTo: inputsContainerView.leftAnchor, constant: 12).isActive = true
emailTextField.topAnchor.constraint(equalTo: nameTextField.bottomAnchor).isActive = true
emailTextField.widthAnchor.constraint(equalTo: inputsContainerView.widthAnchor).isActive = true
emailTextFieldHeightAnchor = emailTextField.heightAnchor.constraint(equalTo: inputsContainerView.heightAnchor, multiplier: 1/3)
emailTextFieldHeightAnchor?.isActive = true
//need x, y, width, height constraints
emailSeparatorView.leftAnchor.constraint(equalTo: inputsContainerView.leftAnchor).isActive = true
emailSeparatorView.topAnchor.constraint(equalTo: emailTextField.bottomAnchor).isActive = true
emailSeparatorView.widthAnchor.constraint(equalTo: inputsContainerView.widthAnchor).isActive = true
emailSeparatorView.heightAnchor.constraint(equalToConstant: 1).isActive = true
//need x, y, width, height constraints
passwordTextField.leftAnchor.constraint(equalTo: inputsContainerView.leftAnchor, constant: 12).isActive = true
passwordTextField.topAnchor.constraint(equalTo: emailTextField.bottomAnchor).isActive = true
passwordTextField.widthAnchor.constraint(equalTo: inputsContainerView.widthAnchor).isActive = true
passwordTextFieldHeightAnchor = passwordTextField.heightAnchor.constraint(equalTo: inputsContainerView.heightAnchor, multiplier: 1/3)
passwordTextFieldHeightAnchor?.isActive = true
}
func setupLoginRegisterButton() {
//need x, y, width, height constraints
loginRegisterButton.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
loginRegisterButton.topAnchor.constraint(equalTo: inputsContainerView.bottomAnchor, constant: 12).isActive = true
loginRegisterButton.widthAnchor.constraint(equalTo: inputsContainerView.widthAnchor).isActive = true
loginRegisterButton.heightAnchor.constraint(equalToConstant: 50).isActive = true
}
override var preferredStatusBarStyle : UIStatusBarStyle {
return .lightContent
}
}
extension UIColor {
convenience init(r: CGFloat, g: CGFloat, b: CGFloat) {
self.init(red: r/255, green: g/255, blue: b/255, alpha: 1)
}
}
要显示活动指标，首先在类级别上声明它然后初始化。
var activityIndicator:UIActivityIndicatorView!
然后在您的ViewDidload((方法中，初始化ActivityIndicator。
activityIndicator = UIActivityIndicatorView(activityIndicatorStyle: .gray)
activityIndicator.center = view.center
activityIndicator.isHidden = true
self.view.addSubview(activityIndicator)
您可以在视图控制器中编写两种方法来启动和停止活动指示器，为：
func displayActivityIndicatorView() -> () {
UIApplication.shared.beginIgnoringInteractionEvents()
self.view.bringSubview(toFront: self.activityIndicator)
self.activityIndicator.isHidden = false
self.activityIndicator.startAnimating()
}
func hideActivityIndicatorView() -> () {
if !self.activityIndicator.isHidden{
DispatchQueue.main.async {
UIApplication.shared.endIgnoringInteractionEvents()
self.activityIndicator.stopAnimating()
self.activityIndicator.isHidden = true
}
}
}
现在，在验证登录数据并击中登录API之前，请启动活动指示器。
func handleLogin() {
guard let email = emailTextField.text, let password = passwordTextField.text else {
print("Form is not valid")
return
}
//start activity indicator
self. displayActivityIndicatorView()
FIRAuth.auth()?.signIn(withEmail: email, password: password, completion: { (user, error) in
if error != nil {
print(error ?? "")
//stop activity indicator
self. hideActivityIndicatorView()
return
}
//successfully logged in our user
//stop activity indicator
self. hideActivityIndicatorView()
self.messagesController?.fetchUserAndSetupNavBarTitle()
self.dismiss(animated: true, completion: nil)
})
}
步骤1：
在代码中某个地方创建活动指示器。特别是在 viewDidload 如果要以编程方式创建它，或者要以编程方式显示具有警报设计的活动指标。
步骤2：显示活动指示器
有一个按钮，例如登录或 register 。在那里，您将启动以显示活动指示器并开始进行动画。
步骤3：隐藏活动指示器
您将在 firauth.auth((？signin ..... 登录处理程序中隐藏活动指示器。就像
[indicator stopAnimating];
[indicator isHidden:YES];
该登录方法中有两种情况。一个是错误，另一个是成功的。更好地向用户或其他东西显示错误警报。希望您会发现该解决方案有帮助。：(
您可以使用以下代码。
let alert = UIAlertController(title: nil, message: "Please wait...", preferredStyle: .alert)
alert.view.tintColor = UIColor.black
let loadingIndicator: UIActivityIndicatorView = UIActivityIndicatorView(frame: CGRect(x:10, y:5, width:50, height:50)) as UIActivityIndicatorView
loadingIndicator.hidesWhenStopped = true
loadingIndicator.activityIndicatorViewStyle = UIActivityIndicatorViewStyle.gray
loadingIndicator.color = UIColor(red: 255.0/255, green: 65.0/255, blue: 42.0/255,alpha : 1.0)
loadingIndicator.startAnimating();
alert.view.addSubview(loadingIndicator)
present(alert, animated: true, completion: nil)
///dismisss///
dismiss(animated: false, completion: nil)