Added in default state machines

Example-iOS/Source/Examples/Storyboard/StateMachine.swift

@@ -35,6 +35,8 @@ class StateMachineView: UIView {
 }
 
 class StateMachineViewController: UIViewController {
+    // MARK: RiveViewModel
+    // This view model specifies the exact StateMachine that it wants from the file
     var viewModel = RiveViewModel(fileName: "skills", stateMachineName: "Designer's Test")
 
     override public func loadView() {
@@ -47,16 +49,16 @@ class StateMachineViewController: UIViewController {
         viewModel.setView(stateMachineView.riveView)
 
         stateMachineView.beginnerButtonAction = {
-            try? self.viewModel.setInput("Level", value: 0.0)
+            self.viewModel.setInput("Level", value: 0.0)
         }
         stateMachineView.intermediateButtonAction = {
-            try? self.viewModel.setInput("Level", value: 1.0)
+            self.viewModel.setInput("Level", value: 1.0)
         }
         stateMachineView.expertButtonAction = {
-            try? self.viewModel.setInput("Level", value: 2.0)
+            self.viewModel.setInput("Level", value: 2.0)
         }
         stateMachineView.resetButtonAction = {
-            try? self.viewModel.reset()
+            self.viewModel.reset()
         }
     }
 

Example-iOS/Source/Examples/SwiftUI/SwiftCannonGame.swift

@@ -13,6 +13,11 @@ struct SwiftCannonGame: DismissableView {
     var dismiss: () -> Void = {}
 
     var body: some View {
-        RiveViewModel(fileName: "bullet_man_game", stateMachineName: "State Machine 1").view()
+        // MARK: RiveViewModel
+        // This view model controls a file configured with:
+        // - StateMachine
+        // - Listeners
+
+        RiveViewModel(fileName: "bullet_man_game").view()
     }
 }

Example-iOS/Source/Examples/SwiftUI/SwiftMeshAnimation.swift

@@ -10,16 +10,19 @@ import SwiftUI
 import RiveRuntime
 
 struct SwiftMeshAnimation: DismissableView {
+    var dismiss: () -> Void = {}
+
+    // MARK: RiveViewModel
+    // This view model specifies the exact StateMachine that it wants from the file
     var tapePlayer = RiveViewModel(fileName: "prop_example", stateMachineName: "State Machine 1")
     @State var isTapped: Bool = false
-    var dismiss: () -> Void = {}
 
     var body: some View {
         tapePlayer.view()
             .aspectRatio(1, contentMode: .fit)
             .onTapGesture {
                 isTapped = !isTapped
-                try? tapePlayer.setInput("Hover", value: isTapped)
+                tapePlayer.setInput("Hover", value: isTapped)
             }
     }
 }

Example-iOS/Source/Examples/SwiftUI/SwiftStateMachine.swift

@@ -10,9 +10,13 @@ import SwiftUI
 import RiveRuntime
 
 struct SwiftStateMachine: DismissableView {
-    var stateChanger = RiveViewModel(fileName: "skills", stateMachineName: "Designer's Test")
     var dismiss: () -> Void = {}
 
+    // MARK: RiveViewModel
+    // This view model specifies the exact StateMachine that it wants from the file
+
+    var stateChanger = RiveViewModel(fileName: "skills", stateMachineName: "Designer's Test")
+
     var body: some View {
         ScrollView{
             VStack {
@@ -21,13 +25,13 @@ struct SwiftStateMachine: DismissableView {
 
                 HStack{
                     Button("Beginner") {
-                        try? stateChanger.setInput("Level", value: 0.0)
+                        stateChanger.setInput("Level", value: 0.0)
                     }
                     Button("Intermediate") {
-                        try? stateChanger.setInput("Level", value: 1.0)
+                        stateChanger.setInput("Level", value: 1.0)
                     }
                     Button("Expert") {
-                        try? stateChanger.setInput("Level", value: 2.0)
+                        stateChanger.setInput("Level", value: 2.0)
                     }
                 }
 

Example-iOS/Source/Examples/SwiftUI/SwiftTouchEvents.swift

@@ -11,13 +11,19 @@ import RiveRuntime
 
 struct SwiftTouchEvents: DismissableView {
     var dismiss: () -> Void = {}
+
+    // MARK: RiveViewModels
+    // Each of the these view models controls a file configured with:
+    // - State Machine
+    // - Listeners
+
     @StateObject var clock = ClockViewModel()
-    @StateObject var jelly = RiveViewModel(fileName: "hero_editor", stateMachineName: "Jellyfish")
-    @StateObject var playButton = RiveViewModel(fileName: "play_button_event_example", stateMachineName: "State Machine")
-    @StateObject var lighthouse = RiveViewModel(fileName: "switch_event_example", stateMachineName: "Main State Machine")
-    @StateObject var eightball = RiveViewModel(fileName: "magic_8-ball_v2", stateMachineName: "Main State Machine")
-    @StateObject var bearGuy = RiveViewModel(fileName: "leg_day_events_example", stateMachineName: "Don't Skip Leg Day")
-    @StateObject var toggle = RiveViewModel(fileName: "light_switch", stateMachineName: "Switch")
+    @StateObject var jelly = RiveViewModel(fileName: "hero_editor")
+    @StateObject var playButton = RiveViewModel(fileName: "play_button_event_example")
+    @StateObject var lighthouse = RiveViewModel(fileName: "switch_event_example")
+    @StateObject var eightball = RiveViewModel(fileName: "magic_8-ball_v2")
+    @StateObject var bearGuy = RiveViewModel(fileName: "leg_day_events_example")
+    @StateObject var toggle = RiveViewModel(fileName: "light_switch")
 
     var body: some View {
         ScrollView {

Source/Components/RiveModel.swift

@@ -30,43 +30,56 @@ open class RiveModel: ObservableObject {
 
     open func setArtboard(_ name: String) throws {
         do { artboard = try riveFile.artboard(fromName: name) }
-        catch { throw RiveModelError.invalidArtboard(name: name) }
+        catch { throw RiveModelError.invalidArtboard("Name \(name) not found") }
     }
 
     open func setArtboard(_ index: Int? = nil) throws {
         if let index = index {
             do { artboard = try riveFile.artboard(from: index) }
-            catch { throw RiveModelError.invalidArtboard(index: index) }
+            catch { throw RiveModelError.invalidArtboard("Index \(index) not found") }
         } else {
             // This tries to find the 'default' Artboard
             do { artboard = try riveFile.artboard() }
-            catch { throw RiveModelError.invalidArtboard(message: "No Default Artboard") }
+            catch { throw RiveModelError.invalidArtboard("No Default Artboard") }
         }
     }
 
     open func setStateMachine(_ name: String) throws {
         do { stateMachine = try artboard.stateMachine(fromName: name) }
-        catch { throw RiveModelError.invalidStateMachine(name: name) }
+        catch { throw RiveModelError.invalidStateMachine("Name \(name) not found") }
     }
 
     open func setStateMachine(_ index: Int? = nil) throws {
-        // Defaults to 0 as it's assumed to be the first element in the collection
-        let index = index ?? 0
-        do { stateMachine = try artboard.stateMachine(from: index) }
-        catch { throw RiveModelError.invalidStateMachine(index: index) }
+        do {
+            // Set by index
+            if let index = index {
+                stateMachine = try artboard.stateMachine(from: index)
+            }
+
+            // Set from Artboard's default StateMachine configured in editor
+            else if let defaultStateMachine = artboard.defaultStateMachine() {
+                stateMachine = defaultStateMachine
+            }
+
+            // Set by index 0 as a fallback
+            else {
+                stateMachine = try artboard.stateMachine(from: 0)
+            }
+        }
+        catch { throw RiveModelError.invalidStateMachine("Index \(index ?? 0) not found") }
     }
 
     open func setAnimation(_ name: String) throws {
         guard animation?.name() != name else { return }
         do { animation = try artboard.animation(fromName: name) }
-        catch { throw RiveModelError.invalidAnimation(name: name) }
+        catch { throw RiveModelError.invalidAnimation("Name \(name) not found") }
     }
 
     open func setAnimation(_ index: Int? = nil) throws {
         // Defaults to 0 as it's assumed to be the first element in the collection
         let index = index ?? 0
         do { animation = try artboard.animation(from: index) }
-        catch { throw RiveModelError.invalidAnimation(index: index) }
+        catch { throw RiveModelError.invalidAnimation("Index \(index) not found") }
     }
 
     // MARK: -
@@ -86,8 +99,8 @@ open class RiveModel: ObservableObject {
     }
 
     enum RiveModelError: Error {
-        case invalidStateMachine(name: String), invalidStateMachine(index: Int)
-        case invalidAnimation(name: String), invalidAnimation(index: Int)
-        case invalidArtboard(name: String), invalidArtboard(index: Int), invalidArtboard(message: String)
+        case invalidStateMachine(_ message: String)
+        case invalidAnimation(_ message: String)
+        case invalidArtboard(_ message: String)
     }
 }

Source/Components/RiveViewModel.swift

@@ -226,28 +226,35 @@ open class RiveViewModel: NSObject, ObservableObject, RiveFileDelegate, RiveStat
 
     /// Instantiates elements in the model needed to play in a `RiveView`
     private func configureModel(artboardName: String? = nil, stateMachineName: String? = nil, animationName: String? = nil) throws {
+        guard let model = riveModel else { fatalError("Cannot configure nil RiveModel") }
+
         if let name = artboardName {
-            try riveModel?.setArtboard(name)
+            try model.setArtboard(name)
         } else {
             // Keep current Artboard if there is one
-            if riveModel?.artboard == nil {
+            if model.artboard == nil {
                 // Set default Artboard if not
-                try riveModel?.setArtboard()
+                try model.setArtboard()
             }
         }
 
-        riveModel?.animation = nil
-        riveModel?.stateMachine = nil
+        model.animation = nil
+        model.stateMachine = nil
 
         if let name = stateMachineName {
-            try riveModel?.setStateMachine(name)
+            try model.setStateMachine(name)
         }
         else if let name = animationName {
-            try riveModel?.setAnimation(name)
+            try model.setAnimation(name)
         }
+
+        // Find defaults
         else {
-            // Set default Animation
-            try riveModel?.setAnimation()
+            // Attempts to set a default StateMachine first
+            if ((try? model.setStateMachine()) == nil) {
+                // If it fails, attempts a default Animation
+                try model.setAnimation()
+            }
         }
     }
 

Source/Renderer/RiveArtboard.mm

@@ -114,6 +114,15 @@ - (RiveStateMachineInstance *)stateMachineFromName:(NSString *)name error:(NSErr
     return [[RiveStateMachineInstance alloc] initWithStateMachine: machine];
 }
 
+- (RiveStateMachineInstance *)defaultStateMachine {
+    rive::StateMachineInstance *machine = _artboardInstance->defaultStateMachine().release();
+    if (machine == nullptr) {
+//        *error = [NSError errorWithDomain:RiveErrorDomain code:RiveNoStateMachineFound userInfo:@{NSLocalizedDescriptionKey: [NSString stringWithFormat: @"No default State Machine found."], @"name": @"NoStateMachineFound"}];
+        return nil;
+    }
+    return [[RiveStateMachineInstance alloc] initWithStateMachine:machine];
+}
+
 - (NSArray *)stateMachineNames{
     NSMutableArray *stateMachineNames = [NSMutableArray array];
     for (NSUInteger i=0; i<[self stateMachineCount]; i++){

Source/Renderer/include/RiveArtboard.h

@@ -31,6 +31,7 @@ NS_ASSUME_NONNULL_BEGIN
 - (NSArray<NSString *> *)stateMachineNames;
 - (RiveStateMachineInstance * __nullable)stateMachineFromIndex:(NSInteger)index error:(NSError **)error;
 - (RiveStateMachineInstance * __nullable)stateMachineFromName:(NSString *)name error:(NSError **)error;
+- (RiveStateMachineInstance * __nullable)defaultStateMachine;
 
 - (void)advanceBy:(double)elapsedSeconds;
 - (void)draw:(RiveRenderer *)renderer;