1 files changed, 148 insertions, 0 deletions
diff --git a/Example/tvOSSample/tvOSSample/StorageViewController.swift b/Example/tvOSSample/tvOSSample/StorageViewController.swift
new file mode 100644
index 0000000..4416649
--- /dev/null
+++ b/Example/tvOSSample/tvOSSample/StorageViewController.swift
@@ -0,0 +1,148 @@
+// Copyright 2017 Google
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import UIKit
+import FirebaseStorage
+
+class StorageViewController: UIViewController {
+  /// An enum describing the different states of the view controller.
+  private enum UIState: Equatable {
+    /// No image is being shown, waiting on user action.
+    case cleared
+
+    /// Currently downloading from Firebase.
+    case downloading(StorageTask)
+
+    /// The image has downloaded and should be displayed.
+    case downloaded(UIImage)
+
+    /// Show an error message and stop downloading.
+    case failed(String)
+
+    /// Equatable support for UIState.
+    static func ==(lhs: StorageViewController.UIState, rhs: StorageViewController.UIState) -> Bool {
+      switch (lhs, rhs) {
+      case (.cleared, .cleared): return true
+      case (.downloading, .downloading): return true
+      case (.downloaded, .downloaded): return true
+      case (.failed, .failed): return true
+      default: return false
+      }
+    }
+  }
+
+  /// MARK: - Properties
+
+  /// The current internal state of the view controller.
+  private var state: UIState = .cleared {
+    didSet { changeState(from: oldValue, to: state) }
+  }
+
+  // MARK: Interface
+
+  /// Image view to display the downloaded image.
+  @IBOutlet weak var imageView: UIImageView!
+
+  /// The download button.
+  @IBOutlet weak var downloadButton: UIButton!
+
+  /// The clear button.
+  @IBOutlet weak var clearButton: UIButton!
+
+  /// A visual representation of the state.
+  @IBOutlet weak var stateLabel: UILabel!
+
+  // MARK: - User Actions
+
+  @IBAction func downloadButtonHit(_ sender: UIButton) {
+    guard case .cleared = state else { return }
+
+    // Start the download.
+    let storage = Storage.storage()
+    let ref = storage.reference(withPath: Constants.downloadPath)
+    // TODO: Show progress bar here using proper API.
+    let task = ref.getData(maxSize: Constants.maxSize) { [unowned self] (data, error) in
+      guard let data = data else {
+        self.state = .failed("Error downloading: \(error!.localizedDescription)")
+        return
+      }
+
+      // Create a UIImage from the PNG data.
+      guard let image = UIImage(data: data) else {
+        self.state = .failed("Unable to initialize image with data downloaded.")
+        return
+      }
+
+      self.state = .downloaded(image)
+    }
+
+    // The completion block above could be run before this line in some situations. If that's the
+    // case, we don't need to do anything else and can return.
+    if case .downloaded = state { return }
+
+    // Set the state to downloading!
+    state = .downloading(task)
+  }
+
+  @IBAction func clearButtonHit(_ sender: UIButton) {
+    guard case .downloaded = state else { return }
+
+    state = .cleared
+  }
+
+  // MARK: - State Management
+
+  /// Changing from old state to new state.
+  private func changeState(from oldState: UIState, to newState: UIState) {
+    if oldState == newState { return }
+
+    switch (oldState, newState) {
+    // Regular state, start downloading the image.
+    case (.cleared, .downloading(_)):
+      // TODO: Update the UI with a spinner? Progress update?
+      stateLabel.text = "State: Downloading..."
+
+    //  Download complete, ensure the download button is still off and enable the clear button.
+    case (_, .downloaded(let image)):
+      imageView.image = image
+      stateLabel.text = "State: Image downloaded!"
+
+    // Clear everything and reset to the original state.
+    case (_, .cleared):
+      imageView.image = nil
+      stateLabel.text = "State: Pending download"
+
+    // An error occurred.
+    case (_, .failed(let error)):
+      stateLabel.text = "State: \(error)"
+
+    // For now, as the default, throw a fatal error because it's an unexpected state. This will
+    // allow us to catch it immediately and add the required action or fix the bug.
+    default:
+      fatalError("Programmer error! Tried to go from \(oldState) to \(newState)")
+    }
+  }
+
+  // MARK: - Constants
+
+  /// Internal constants for this class.
+  private struct Constants {
+    /// The image name to download. Can comment this out and replace it with the other below it as
+    /// part of the demo. Ensure that Storage has an image uploaded to this path for this to
+    /// function properly.
+    static let downloadPath = "YOUR_IMAGE_NAME.jpg"
+
+    static let maxSize: Int64 = 1024 * 1024 * 10 // ~10MB
+  }
+}