session-ios/SignalMessaging/ViewControllers/ModalActivityIndicatorViewController.swift
2018-08-27 10:21:03 -04:00

157 lines
5.1 KiB
Swift

//
// Copyright (c) 2018 Open Whisper Systems. All rights reserved.
//
import Foundation
import MediaPlayer
import SignalServiceKit
// A modal view that be used during blocking interactions (e.g. waiting on response from
// service or on the completion of a long-running local operation).
@objc
public class ModalActivityIndicatorViewController: OWSViewController {
let canCancel: Bool
@objc
public var wasCancelled: Bool = false
var activityIndicator: UIActivityIndicatorView?
var presentTimer: Timer?
var wasDimissed: Bool = false
// MARK: Initializers
@available(*, unavailable, message:"use other constructor instead.")
public required init?(coder aDecoder: NSCoder) {
notImplemented()
}
public required init(canCancel: Bool) {
self.canCancel = canCancel
super.init(nibName: nil, bundle: nil)
}
@objc
public class func present(fromViewController: UIViewController,
canCancel: Bool, backgroundBlock : @escaping (ModalActivityIndicatorViewController) -> Void) {
AssertIsOnMainThread()
let view = ModalActivityIndicatorViewController(canCancel: canCancel)
// Present this modal _over_ the current view contents.
view.modalPresentationStyle = .overFullScreen
fromViewController.present(view,
animated: false) {
DispatchQueue.global().async {
backgroundBlock(view)
}
}
}
@objc
public func dismiss(completion : @escaping () -> Void) {
AssertIsOnMainThread()
if !wasDimissed {
// Only dismiss once.
self.dismiss(animated: false, completion: completion)
wasDimissed = true
} else {
// If already dismissed, wait a beat then call completion.
DispatchQueue.main.async {
completion()
}
}
}
public override func loadView() {
super.loadView()
self.view.backgroundColor = (Theme.isDarkThemeEnabled
? UIColor(white: 0.35, alpha: 0.35)
: UIColor(white: 0, alpha: 0.25))
self.view.isOpaque = false
let activityIndicator = UIActivityIndicatorView(activityIndicatorStyle: .whiteLarge)
self.activityIndicator = activityIndicator
self.view.addSubview(activityIndicator)
activityIndicator.autoCenterInSuperview()
if canCancel {
let cancelButton = UIButton(type: .custom)
cancelButton.setTitle(CommonStrings.cancelButton, for: .normal)
cancelButton.setTitleColor(UIColor.white, for: .normal)
cancelButton.backgroundColor = UIColor.ows_darkGray
cancelButton.titleLabel?.font = UIFont.ows_mediumFont(withSize: ScaleFromIPhone5To7Plus(18, 22))
cancelButton.layer.cornerRadius = ScaleFromIPhone5To7Plus(4, 5)
cancelButton.clipsToBounds = true
cancelButton.addTarget(self, action: #selector(cancelPressed), for: .touchUpInside)
let buttonWidth = ScaleFromIPhone5To7Plus(140, 160)
let buttonHeight = ScaleFromIPhone5To7Plus(40, 50)
self.view.addSubview(cancelButton)
cancelButton.autoHCenterInSuperview()
cancelButton.autoPinEdge(toSuperviewEdge: .bottom, withInset: 50)
cancelButton.autoSetDimension(.width, toSize: buttonWidth)
cancelButton.autoSetDimension(.height, toSize: buttonHeight)
}
// Hide the modal until the presentation animation completes.
self.view.layer.opacity = 0.0
}
public override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
self.activityIndicator?.startAnimating()
// Hide the the modal and wait for a second before revealing it,
// to avoid "blipping" in the modal during short blocking operations.
//
// NOTE: It will still intercept user interactions while hidden, as it
// should.
let kPresentationDelaySeconds = TimeInterval(1)
self.presentTimer?.invalidate()
self.presentTimer = Timer.weakScheduledTimer(withTimeInterval: kPresentationDelaySeconds, target: self, selector: #selector(presentTimerFired), userInfo: nil, repeats: false)
}
public override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(animated)
clearTimer()
}
public override func viewDidDisappear(_ animated: Bool) {
super.viewDidDisappear(animated)
self.activityIndicator?.stopAnimating()
clearTimer()
}
private func clearTimer() {
self.presentTimer?.invalidate()
self.presentTimer = nil
}
@objc func presentTimerFired() {
AssertIsOnMainThread()
clearTimer()
// Fade in the modal.
UIView.animate(withDuration: 0.35) {
self.view.layer.opacity = 1.0
}
}
@objc func cancelPressed() {
AssertIsOnMainThread()
wasCancelled = true
dismiss {
}
}
}