More progress with the Swift example

examples/Kittens/Sample/ViewController.m

@@ -165,28 +165,24 @@ static const NSInteger kMaxLitterSize = 100;        // max number of kitten cell
 
 - (void)tableView:(UITableView *)tableView willBeginBatchFetchWithContext:(ASBatchContext *)context
 {
-  dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
+  dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(1 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
-    sleep(1);
+    // populate a new array of random-sized kittens
-    dispatch_async(dispatch_get_main_queue(), ^{
+    NSArray *moarKittens = [self createLitterWithSize:kLitterBatchSize];
 
-      // populate a new array of random-sized kittens
+    NSMutableArray *indexPaths = [[NSMutableArray alloc] init];
-      NSArray *moarKittens = [self createLitterWithSize:kLitterBatchSize];
       
-      NSMutableArray *indexPaths = [[NSMutableArray alloc] init];
+    // find number of kittens in the data source and create their indexPaths
+    NSInteger existingRows = _kittenDataSource.count + 1;
       
-      // find number of kittens in the data source and create their indexPaths
+    for (NSInteger i = 0; i < moarKittens.count; i++) {
-      NSInteger existingRows = _kittenDataSource.count + 1;
+      [indexPaths addObject:[NSIndexPath indexPathForRow:existingRows + i inSection:0]];
+    }
 
-      for (NSInteger i = 0; i < moarKittens.count; i++) {
+    // add new kittens to the data source & notify table of new indexpaths
-        [indexPaths addObject:[NSIndexPath indexPathForRow:existingRows + i inSection:0]];
+    [_kittenDataSource addObjectsFromArray:moarKittens];
-      }
+    [tableView insertRowsAtIndexPaths:indexPaths withRowAnimation:UITableViewRowAnimationFade];
 
-      // add new kittens to the data source & notify table of new indexpaths
+    [context completeBatchFetching:YES];
-      [_kittenDataSource addObjectsFromArray:moarKittens];
-      [tableView insertRowsAtIndexPaths:indexPaths withRowAnimation:UITableViewRowAnimationFade];
-
-      [context completeBatchFetching:YES];
-    });
   });
 }
 

examples/Swift/Sample.xcodeproj/project.pbxproj

@@ -13,6 +13,7 @@
 		6C5053DB19EE266A00E385DE /* Default-667h@2x.png in Resources */ = {isa = PBXBuildFile; fileRef = 6C5053D919EE266A00E385DE /* Default-667h@2x.png */; };
 		6C5053DC19EE266A00E385DE /* Default-736h@3x.png in Resources */ = {isa = PBXBuildFile; fileRef = 6C5053DA19EE266A00E385DE /* Default-736h@3x.png */; };
 		92E46E91A7D47AEC5B2B2F55 /* Pods.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 7FC29F18AE7C8C204A5CD4F2 /* Pods.framework */; };
+		CCB01CAB1C5FEA6E00CA64C4 /* TailLoadingCellNode.swift in Sources */ = {isa = PBXBuildFile; fileRef = CCB01CAA1C5FEA6E00CA64C4 /* TailLoadingCellNode.swift */; };
 /* End PBXBuildFile section */
 
 /* Begin PBXFileReference section */
@@ -25,6 +26,7 @@
 		6C5053DA19EE266A00E385DE /* Default-736h@3x.png */ = {isa = PBXFileReference; lastKnownFileType = image.png; path = "Default-736h@3x.png"; sourceTree = SOURCE_ROOT; };
 		7FC29F18AE7C8C204A5CD4F2 /* Pods.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; includeInIndex = 0; path = Pods.framework; sourceTree = BUILT_PRODUCTS_DIR; };
 		841652076B3E9351337AA7C7 /* Pods.debug.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = Pods.debug.xcconfig; path = "Pods/Target Support Files/Pods/Pods.debug.xcconfig"; sourceTree = "<group>"; };
+		CCB01CAA1C5FEA6E00CA64C4 /* TailLoadingCellNode.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = TailLoadingCellNode.swift; sourceTree = "<group>"; };
 		E3EE87D12CE3EF73FAE2EF02 /* Pods.release.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = Pods.release.xcconfig; path = "Pods/Target Support Files/Pods/Pods.release.xcconfig"; sourceTree = "<group>"; };
 /* End PBXFileReference section */
 
@@ -64,6 +66,7 @@
 		050E7C7019D22E19004363C2 /* Sample */ = {
 			isa = PBXGroup;
 			children = (
+				CCB01CAA1C5FEA6E00CA64C4 /* TailLoadingCellNode.swift */,
 				050E7C7319D22E19004363C2 /* AppDelegate.swift */,
 				050E7C7519D22E19004363C2 /* ViewController.swift */,
 				050E7C7119D22E19004363C2 /* Supporting Files */,
@@ -130,7 +133,7 @@
 			attributes = {
 				LastSwiftMigration = 0700;
 				LastSwiftUpdateCheck = 0700;
-				LastUpgradeCheck = 0600;
+				LastUpgradeCheck = 0720;
 				ORGANIZATIONNAME = Facebook;
 				TargetAttributes = {
 					050E7C6D19D22E19004363C2 = {
@@ -222,6 +225,7 @@
 			isa = PBXSourcesBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
+				CCB01CAB1C5FEA6E00CA64C4 /* TailLoadingCellNode.swift in Sources */,
 				050E7C7619D22E19004363C2 /* ViewController.swift in Sources */,
 				050E7C7419D22E19004363C2 /* AppDelegate.swift in Sources */,
 			);
@@ -250,6 +254,7 @@
 				"CODE_SIGN_IDENTITY[sdk=iphoneos*]" = "iPhone Developer";
 				COPY_PHASE_STRIP = NO;
 				ENABLE_STRICT_OBJC_MSGSEND = YES;
+				ENABLE_TESTABILITY = YES;
 				GCC_C_LANGUAGE_STANDARD = gnu99;
 				GCC_DYNAMIC_NO_PIC = NO;
 				GCC_OPTIMIZATION_LEVEL = 0;
@@ -314,6 +319,7 @@
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				INFOPLIST_FILE = Sample/Info.plist;
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks";
+				PRODUCT_BUNDLE_IDENTIFIER = "com.facebook.AsyncDisplayKit.$(PRODUCT_NAME:rfc1034identifier)";
 				PRODUCT_NAME = "$(TARGET_NAME)";
 			};
 			name = Debug;
@@ -325,6 +331,7 @@
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				INFOPLIST_FILE = Sample/Info.plist;
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks";
+				PRODUCT_BUNDLE_IDENTIFIER = "com.facebook.AsyncDisplayKit.$(PRODUCT_NAME:rfc1034identifier)";
 				PRODUCT_NAME = "$(TARGET_NAME)";
 			};
 			name = Release;

examples/Swift/Sample.xcodeproj/xcshareddata/xcschemes/Sample.xcscheme

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <Scheme
-   LastUpgradeVersion = "0620"
+   LastUpgradeVersion = "0720"
    version = "1.3">
    <BuildAction
       parallelizeBuildables = "YES"
@@ -23,10 +23,10 @@
       </BuildActionEntries>
    </BuildAction>
    <TestAction
+      buildConfiguration = "Debug"
       selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
-      shouldUseLaunchSchemeArgsEnv = "YES"
+      shouldUseLaunchSchemeArgsEnv = "YES">
-      buildConfiguration = "Debug">
       <Testables>
       </Testables>
       <MacroExpansion>
@@ -38,15 +38,18 @@
             ReferencedContainer = "container:Sample.xcodeproj">
          </BuildableReference>
       </MacroExpansion>
+      <AdditionalOptions>
+      </AdditionalOptions>
    </TestAction>
    <LaunchAction
+      buildConfiguration = "Debug"
       selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
       selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
       launchStyle = "0"
       useCustomWorkingDirectory = "NO"
-      buildConfiguration = "Debug"
       ignoresPersistentStateOnLaunch = "NO"
       debugDocumentVersioning = "YES"
+      debugServiceExtension = "internal"
       allowLocationSimulation = "YES">
       <BuildableProductRunnable
          runnableDebuggingMode = "0">
@@ -62,10 +65,10 @@
       </AdditionalOptions>
    </LaunchAction>
    <ProfileAction
+      buildConfiguration = "Release"
       shouldUseLaunchSchemeArgsEnv = "YES"
       savedToolIdentifier = ""
       useCustomWorkingDirectory = "NO"
-      buildConfiguration = "Release"
       debugDocumentVersioning = "YES">
       <BuildableProductRunnable
          runnableDebuggingMode = "0">

examples/Swift/Sample.xcworkspace/contents.xcworkspacedata

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Workspace
+   version = "1.0">
+   <FileRef
+      location = "group:Sample.xcodeproj">
+   </FileRef>
+   <FileRef
+      location = "group:Pods/Pods.xcodeproj">
+   </FileRef>
+</Workspace>

examples/Swift/Sample/Info.plist

@@ -7,7 +7,7 @@
 	<key>CFBundleExecutable</key>
 	<string>$(EXECUTABLE_NAME)</string>
 	<key>CFBundleIdentifier</key>
-	<string>com.facebook.AsyncDisplayKit.$(PRODUCT_NAME:rfc1034identifier)</string>
+	<string>$(PRODUCT_BUNDLE_IDENTIFIER)</string>
 	<key>CFBundleInfoDictionaryVersion</key>
 	<string>6.0</string>
 	<key>CFBundleName</key>

examples/Swift/Sample/TailLoadingCellNode.swift

@@ -0,0 +1,53 @@
+//
+//  TailLoadingCellNode.swift
+//  Sample
+//
+//  Created by Adlai Holler on 2/1/16.
+//  Copyright © 2016 Facebook. All rights reserved.
+//
+
+import AsyncDisplayKit
+import UIKit
+
+final class TailLoadingCellNode: ASCellNode {
+  let spinner = SpinnerNode()
+  let text = ASTextNode()
+
+  override init() {
+    super.init()
+    addSubnode(text)
+    text.attributedString = NSAttributedString(
+      string: "Loading…",
+      attributes: [
+        NSFontAttributeName: UIFont.systemFontOfSize(12),
+        NSForegroundColorAttributeName: UIColor.lightGrayColor(),
+        NSKernAttributeName: -0.3
+      ])
+    addSubnode(spinner)
+  }
+
+  override func layoutSpecThatFits(constrainedSize: ASSizeRange) -> ASLayoutSpec {
+    return ASStackLayoutSpec(
+      direction: .Horizontal,
+      spacing: 16,
+      justifyContent: .Center,
+      alignItems: .Center,
+      children: [ text, spinner ])
+  }
+}
+
+final class SpinnerNode: ASDisplayNode {
+  var activityIndicatorView: UIActivityIndicatorView {
+    return view as! UIActivityIndicatorView
+  }
+
+  override init() {
+    super.init(viewBlock: { UIActivityIndicatorView(activityIndicatorStyle: .Gray) }, didLoadBlock: nil)
+    preferredFrameSize.height = 32
+  }
+
+  override func didLoad() {
+    super.didLoad()
+    activityIndicatorView.startAnimating()
+  }
+}

examples/Swift/Sample/ViewController.swift

@@ -14,10 +14,23 @@ import AsyncDisplayKit
 
 final class ViewController: ASViewController, ASTableDataSource, ASTableDelegate {
 
+  struct State {
+    var rowCount: Int
+    var showingSpinner: Bool
+    static let empty = State(rowCount: 20, showingSpinner: false)
+  }
+
+  enum Action {
+    case BeginBatchFetch
+    case EndBatchFetch(resultCount: Int)
+  }
+
   var tableNode: ASTableNode {
     return node as! ASTableNode
   }
 
+  private(set) var state: State = .empty
+
   init() {
     super.init(node: ASTableNode())
     tableNode.delegate = self
@@ -35,6 +48,11 @@ final class ViewController: ASViewController, ASTableDataSource, ASTableDelegate
   // MARK: ASTableView data source and delegate.
 
   func tableView(tableView: ASTableView, nodeForRowAtIndexPath indexPath: NSIndexPath) -> ASCellNode {
+    NSLog("Number of rows %d", tableView.numberOfRowsInSection(0))
+    if state.showingSpinner && indexPath.row == tableView.numberOfRowsInSection(0) - 1 {
+      return TailLoadingCellNode()
+    }
+
     let node = ASTextCellNode()
     node.text = String(format: "[%ld.%ld] says hello!", indexPath.section, indexPath.row)
 
@@ -46,7 +64,70 @@ final class ViewController: ASViewController, ASTableDataSource, ASTableDelegate
   }
 
   func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
-    return 20
+    var count = state.rowCount
+    if state.showingSpinner {
+      count += 1
+    }
+    return count
   }
 
+  func tableView(tableView: ASTableView, willBeginBatchFetchWithContext context: ASBatchContext) {
+    context.cancelBatchFetching()
+    dispatch_async(dispatch_get_main_queue()) {
+      let oldState = self.state
+      self.state = ViewController.handleAction(.BeginBatchFetch, fromState: oldState)
+      self.render(oldState)
+    }
+    return;
+
+    let time = dispatch_time(DISPATCH_TIME_NOW, Int64(NSTimeInterval(NSEC_PER_SEC) * 3))
+    dispatch_after(time, dispatch_get_main_queue()) {
+      let action = Action.EndBatchFetch(resultCount: 20)
+      let oldState = self.state
+      self.state = ViewController.handleAction(action, fromState: oldState)
+      self.render(oldState)
+    	context.completeBatchFetching(true)
+    }
+  }
+
+  func render(oldState: State) {
+    let tableView = tableNode.view
+    tableView.beginUpdates()
+
+    // Add or remove items
+    let rowCountChange = state.rowCount - oldState.rowCount
+    if rowCountChange > 0 {
+      let indexPaths = (oldState.rowCount..<state.rowCount).map { index in
+        NSIndexPath(forRow: index, inSection: 0)
+      }
+      tableView.insertRowsAtIndexPaths(indexPaths, withRowAnimation: .None)
+    } else if rowCountChange < 0 {
+      assertionFailure("Deleting rows is not implemented. YAGNI.")
+    }
+
+    // Add or remove spinner.
+    if state.showingSpinner && !oldState.showingSpinner {
+      if state.showingSpinner {
+        // Add spinner.
+        let spinnerIndexPath = NSIndexPath(forRow: state.rowCount, inSection: 0)
+        tableView.insertRowsAtIndexPaths([ spinnerIndexPath ], withRowAnimation: .None)
+      } else {
+        // Remove spinner.
+        let spinnerIndexPath = NSIndexPath(forRow: oldState.rowCount, inSection: 0)
+        tableView.deleteRowsAtIndexPaths([ spinnerIndexPath ], withRowAnimation: .None)
+      }
+    }
+    tableView.endUpdatesAnimated(false, completion: nil)
+  }
+
+  static func handleAction(action: Action, var fromState state: State) -> State {
+    switch action {
+    case .BeginBatchFetch:
+      state.showingSpinner = true
+    case let .EndBatchFetch(resultCount):
+      state.rowCount += resultCount
+      state.showingSpinner = false
+    }
+    return state
+  }
 }